/*
* Copyright (c) 2019, Alliance for Open Media. All rights reserved.
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
/*!\defgroup gf_group_algo Golden Frame Group
* \ingroup high_level_algo
* Algorithms regarding determining the length of GF groups and defining GF
* group structures.
* @{
*/
/*! @} - end defgroup gf_group_algo */
#include <assert.h>
#include <limits.h>
#include <stdint.h>
#include "aom_dsp/aom_dsp_common.h"
#include "aom_mem/aom_mem.h"
#include "config/aom_config.h"
#include "config/aom_scale_rtcd.h"
#include "aom/aom_codec.h"
#include "aom/aom_encoder.h"
#include "av1/common/av1_common_int.h"
#include "av1/encoder/encoder.h"
#include "av1/encoder/firstpass.h"
#include "av1/encoder/gop_structure.h"
#include "av1/encoder/pass2_strategy.h"
#include "av1/encoder/ratectrl.h"
#include "av1/encoder/rc_utils.h"
#include "av1/encoder/temporal_filter.h"
#if CONFIG_THREE_PASS
#include "av1/encoder/thirdpass.h"
#endif
#include "av1/encoder/tpl_model.h"
#include "av1/encoder/encode_strategy.h"
#define DEFAULT_KF_BOOST 2300
#define DEFAULT_GF_BOOST 2000
#define GROUP_ADAPTIVE_MAXQ 1
static void init_gf_stats(GF_GROUP_STATS *gf_stats);
#if CONFIG_THREE_PASS
static int define_gf_group_pass3(AV1_COMP *cpi, EncodeFrameParams *frame_params,
int is_final_pass);
#endif
// Calculate an active area of the image that discounts formatting
// bars and partially discounts other 0 energy areas.
#define MIN_ACTIVE_AREA 0.5
#define MAX_ACTIVE_AREA 1.0
static double calculate_active_area(
const FRAME_INFO *frame_info,
const FIRSTPASS_STATS *this_frame) {
const double active_pct =
1.0 -
((this_frame->intra_skip_pct / 2) +
((this_frame->inactive_zone_rows * 2) / (
double)frame_info->mb_rows));
return fclamp(active_pct, MIN_ACTIVE_AREA, MAX_ACTIVE_AREA);
}
// Calculate a modified Error used in distributing bits between easier and
// harder frames.
#define ACT_AREA_CORRECTION 0.5
static double calculate_modified_err_new(
const FRAME_INFO *frame_info,
const FIRSTPASS_STATS *total_stats,
const FIRSTPASS_STATS *this_stats,
int vbrbias,
double modified_error_min,
double modified_error_max) {
if (total_stats == NULL) {
return 0;
}
const double av_weight = total_stats->weight / total_stats->count;
const double av_err =
(total_stats->coded_error * av_weight) / total_stats->count;
double modified_error =
av_err * pow(this_stats->coded_error * this_stats->weight /
DOUBLE_DIVIDE_CHECK(av_err),
vbrbias / 100.0);
// Correction for active area. Frames with a reduced active area
// (eg due to formatting bars) have a higher error per mb for the
// remaining active MBs. The correction here assumes that coding
// 0.5N blocks of complexity 2X is a little easier than coding N
// blocks of complexity X.
modified_error *=
pow(calculate_active_area(frame_info, this_stats), ACT_AREA_CORRECTION);
return fclamp(modified_error, modified_error_min, modified_error_max);
}
static double calculate_modified_err(
const FRAME_INFO *frame_info,
const TWO_PASS *twopass,
const AV1EncoderConfig *oxcf,
const FIRSTPASS_STATS *this_frame) {
const FIRSTPASS_STATS *total_stats = twopass->stats_buf_ctx->total_stats;
return calculate_modified_err_new(
frame_info, total_stats, this_frame, oxcf->rc_cfg.vbrbias,
twopass->modified_error_min, twopass->modified_error_max);
}
// Resets the first pass file to the given position using a relative seek from
// the current position.
static void reset_fpf_position(TWO_PASS_FRAME *p_frame,
const FIRSTPASS_STATS *position) {
p_frame->stats_in = position;
}
static int input_stats(TWO_PASS *p, TWO_PASS_FRAME *p_frame,
FIRSTPASS_STATS *fps) {
if (p_frame->stats_in >= p->stats_buf_ctx->stats_in_end)
return EOF;
*fps = *p_frame->stats_in;
++p_frame->stats_in;
return 1;
}
static int input_stats_lap(TWO_PASS *p, TWO_PASS_FRAME *p_frame,
FIRSTPASS_STATS *fps) {
if (p_frame->stats_in >= p->stats_buf_ctx->stats_in_end)
return EOF;
*fps = *p_frame->stats_in;
/* Move old stats[0] out to accommodate for next frame stats */
memmove(p->frame_stats_arr[0], p->frame_stats_arr[1],
(p->stats_buf_ctx->stats_in_end - p_frame->stats_in - 1) *
sizeof(FIRSTPASS_STATS));
p->stats_buf_ctx->stats_in_end--;
return 1;
}
// Read frame stats at an offset from the current position.
static const FIRSTPASS_STATS *read_frame_stats(
const TWO_PASS *p,
const TWO_PASS_FRAME *p_frame,
int offset) {
if ((offset >= 0 &&
p_frame->stats_in + offset >= p->stats_buf_ctx->stats_in_end) ||
(offset < 0 &&
p_frame->stats_in + offset < p->stats_buf_ctx->stats_in_start)) {
return NULL;
}
return &p_frame->stats_in[offset];
}
// This function returns the maximum target rate per frame.
static int frame_max_bits(
const RATE_CONTROL *rc,
const AV1EncoderConfig *oxcf) {
int64_t max_bits = ((int64_t)rc->avg_frame_bandwidth *
(int64_t)oxcf->rc_cfg.vbrmax_section) /
100;
if (max_bits < 0)
max_bits = 0;
else if (max_bits > rc->max_frame_bandwidth)
max_bits = rc->max_frame_bandwidth;
return (
int)max_bits;
}
// Based on history adjust expectations of bits per macroblock.
static void twopass_update_bpm_factor(AV1_COMP *cpi,
int rate_err_tol) {
TWO_PASS *
const twopass = &cpi->ppi->twopass;
const PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
// Based on recent history adjust expectations of bits per macroblock.
double rate_err_factor = 1.0;
const double adj_limit = AOMMAX(0.2, (
double)(100 - rate_err_tol) / 200.0);
const double min_fac = 1.0 - adj_limit;
const double max_fac = 1.0 + adj_limit;
#if CONFIG_THREE_PASS
if (cpi->third_pass_ctx && cpi->third_pass_ctx->frame_info_count > 0) {
int64_t actual_bits = 0;
int64_t target_bits = 0;
double factor = 0.0;
int count = 0;
for (
int i = 0; i < cpi->third_pass_ctx->frame_info_count; i++) {
actual_bits += cpi->third_pass_ctx->frame_info[i].actual_bits;
target_bits += cpi->third_pass_ctx->frame_info[i].bits_allocated;
factor += cpi->third_pass_ctx->frame_info[i].bpm_factor;
count++;
}
if (count == 0) {
factor = 1.0;
}
else {
factor /= (
double)count;
}
factor *= (
double)actual_bits / DOUBLE_DIVIDE_CHECK((
double)target_bits);
if ((twopass->bpm_factor <= 1 && factor < twopass->bpm_factor) ||
(twopass->bpm_factor >= 1 && factor > twopass->bpm_factor)) {
twopass->bpm_factor = factor;
twopass->bpm_factor =
AOMMAX(min_fac, AOMMIN(max_fac, twopass->bpm_factor));
}
}
#endif // CONFIG_THREE_PASS
int err_estimate = p_rc->rate_error_estimate;
int64_t total_actual_bits = p_rc->total_actual_bits;
double rolling_arf_group_actual_bits =
(
double)twopass->rolling_arf_group_actual_bits;
double rolling_arf_group_target_bits =
(
double)twopass->rolling_arf_group_target_bits;
#if CONFIG_FPMT_TEST
const int is_parallel_frame =
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0 ? 1 : 0;
const int simulate_parallel_frame =
cpi->ppi->fpmt_unit_test_cfg == PARALLEL_SIMULATION_ENCODE
? is_parallel_frame
: 0;
total_actual_bits = simulate_parallel_frame ? p_rc->temp_total_actual_bits
: p_rc->total_actual_bits;
rolling_arf_group_target_bits =
(
double)(simulate_parallel_frame
? p_rc->temp_rolling_arf_group_target_bits
: twopass->rolling_arf_group_target_bits);
rolling_arf_group_actual_bits =
(
double)(simulate_parallel_frame
? p_rc->temp_rolling_arf_group_actual_bits
: twopass->rolling_arf_group_actual_bits);
err_estimate = simulate_parallel_frame ? p_rc->temp_rate_error_estimate
: p_rc->rate_error_estimate;
#endif
if ((p_rc->bits_off_target && total_actual_bits > 0) &&
(rolling_arf_group_target_bits >= 1.0)) {
if (rolling_arf_group_actual_bits > rolling_arf_group_target_bits) {
double error_fraction =
(rolling_arf_group_actual_bits - rolling_arf_group_target_bits) /
rolling_arf_group_target_bits;
error_fraction = (error_fraction > 1.0) ? 1.0 : error_fraction;
rate_err_factor = 1.0 + error_fraction;
}
else {
double error_fraction =
(rolling_arf_group_target_bits - rolling_arf_group_actual_bits) /
rolling_arf_group_target_bits;
rate_err_factor = 1.0 - error_fraction;
}
rate_err_factor = AOMMAX(min_fac, AOMMIN(max_fac, rate_err_factor));
}
// Is the rate control trending in the right direction. Only make
// an adjustment if things are getting worse.
if ((rate_err_factor < 1.0 && err_estimate >= 0) ||
(rate_err_factor > 1.0 && err_estimate <= 0)) {
twopass->bpm_factor *= rate_err_factor;
twopass->bpm_factor = AOMMAX(min_fac, AOMMIN(max_fac, twopass->bpm_factor));
}
}
static const double q_div_term[(QINDEX_RANGE >> 4) + 1] = {
18.0, 30.0, 38.0, 44.0, 47.0, 50.0, 52.0, 54.0, 56.0,
58.0, 60.0, 62.0, 64.0, 66.0, 68.0, 70.0, 72.0
};
#define EPMB_SCALER 1250000
static double calc_correction_factor(
double err_per_mb,
int q) {
double power_term = 0.90;
const int index = q >> 4;
const double divisor =
q_div_term[index] +
(((q_div_term[index + 1] - q_div_term[index]) * (q % 16)) / 16.0);
double error_term = EPMB_SCALER * pow(err_per_mb, power_term);
return error_term / divisor;
}
// Similar to find_qindex_by_rate() function in ratectrl.c, but includes
// calculation of a correction_factor.
static int find_qindex_by_rate_with_correction(uint64_t desired_bits_per_mb,
aom_bit_depth_t bit_depth,
double error_per_mb,
double group_weight_factor,
int best_qindex,
int worst_qindex) {
assert(best_qindex <= worst_qindex);
int low = best_qindex;
int high = worst_qindex;
while (low < high) {
const int mid = (low + high) >> 1;
const double q_factor = calc_correction_factor(error_per_mb, mid);
const double q = av1_convert_qindex_to_q(mid, bit_depth);
const uint64_t mid_bits_per_mb =
(uint64_t)((q_factor * group_weight_factor) / q);
if (mid_bits_per_mb > desired_bits_per_mb) {
low = mid + 1;
}
else {
high = mid;
}
}
return low;
}
/*!\brief Choose a target maximum Q for a group of frames
*
* \ingroup rate_control
*
* This function is used to estimate a suitable maximum Q for a
* group of frames. Inititally it is called to get a crude estimate
* for the whole clip. It is then called for each ARF/GF group to get
* a revised estimate for that group.
*
* \param[in] cpi Top-level encoder structure
* \param[in] av_frame_err The average per frame coded error score
* for frames making up this section/group.
* \param[in] inactive_zone Used to mask off /ignore part of the
* frame. The most common use case is where
* a wide format video (e.g. 16:9) is
* letter-boxed into a more square format.
* Here we want to ignore the bands at the
* top and bottom.
* \param[in] av_target_bandwidth The target bits per frame
*
* \return The maximum Q for frames in the group.
*/
static int get_twopass_worst_quality(AV1_COMP *cpi,
const double av_frame_err,
double inactive_zone,
int av_target_bandwidth) {
const RATE_CONTROL *
const rc = &cpi->rc;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
const RateControlCfg *
const rc_cfg = &oxcf->rc_cfg;
inactive_zone = fclamp(inactive_zone, 0.0, 0.9999);
if (av_target_bandwidth <= 0) {
return rc->worst_quality;
// Highest value allowed
}
else {
const int num_mbs = (oxcf->resize_cfg.resize_mode != RESIZE_NONE)
? cpi->initial_mbs
: cpi->common.mi_params.MBs;
const int active_mbs = AOMMAX(1, num_mbs - (
int)(num_mbs * inactive_zone));
const double av_err_per_mb = av_frame_err / (1.0 - inactive_zone);
const uint64_t target_norm_bits_per_mb =
((uint64_t)av_target_bandwidth << BPER_MB_NORMBITS) / active_mbs;
int rate_err_tol = AOMMIN(rc_cfg->under_shoot_pct, rc_cfg->over_shoot_pct);
const double size_factor =
(active_mbs < 500) ? 0.925 : ((active_mbs > 3000) ? 1.05 : 1.0);
const double speed_factor =
AOMMIN(1.02, (0.975 + (0.005 * cpi->oxcf.speed)));
// Update bpm correction factor based on previous GOP rate error.
twopass_update_bpm_factor(cpi, rate_err_tol);
// Try and pick a max Q that will be high enough to encode the
// content at the given rate.
int q = find_qindex_by_rate_with_correction(
target_norm_bits_per_mb, cpi->common.seq_params->bit_depth,
av_err_per_mb,
cpi->ppi->twopass.bpm_factor * speed_factor * size_factor,
rc->best_quality, rc->worst_quality);
// Restriction on active max q for constrained quality mode.
if (rc_cfg->mode == AOM_CQ) q = AOMMAX(q, rc_cfg->cq_level);
return q;
}
}
#define INTRA_PART 0.005
#define DEFAULT_DECAY_LIMIT 0.75
#define LOW_SR_DIFF_TRHESH 0.01
#define NCOUNT_FRAME_II_THRESH 5.0
#define LOW_CODED_ERR_PER_MB 0.01
/* This function considers how the quality of prediction may be deteriorating
* with distance. It comapres the coded error for the last frame and the
* second reference frame (usually two frames old) and also applies a factor
* based on the extent of INTRA coding.
*
* The decay factor is then used to reduce the contribution of frames further
* from the alt-ref or golden frame, to the bitframe boost calculation for that
* alt-ref or golden frame.
*/
static double get_sr_decay_rate(
const FIRSTPASS_STATS *frame) {
double sr_diff = (frame->sr_coded_error - frame->coded_error);
double sr_decay = 1.0;
double modified_pct_inter;
double modified_pcnt_intra;
modified_pct_inter = frame->pcnt_inter;
if ((frame->coded_error > LOW_CODED_ERR_PER_MB) &&
((frame->intra_error / DOUBLE_DIVIDE_CHECK(frame->coded_error)) <
(
double)NCOUNT_FRAME_II_THRESH)) {
modified_pct_inter = frame->pcnt_inter - frame->pcnt_neutral;
}
modified_pcnt_intra = 100 * (1.0 - modified_pct_inter);
if ((sr_diff > LOW_SR_DIFF_TRHESH)) {
double sr_diff_part = ((sr_diff * 0.25) / frame->intra_error);
sr_decay = 1.0 - sr_diff_part - (INTRA_PART * modified_pcnt_intra);
}
return AOMMAX(sr_decay, DEFAULT_DECAY_LIMIT);
}
// This function gives an estimate of how badly we believe the prediction
// quality is decaying from frame to frame.
static double get_zero_motion_factor(
const FIRSTPASS_STATS *frame) {
const double zero_motion_pct = frame->pcnt_inter - frame->pcnt_motion;
double sr_decay = get_sr_decay_rate(frame);
return AOMMIN(sr_decay, zero_motion_pct);
}
#define DEFAULT_ZM_FACTOR 0.5
static double get_prediction_decay_rate(
const FIRSTPASS_STATS *frame_stats) {
const double sr_decay_rate = get_sr_decay_rate(frame_stats);
double zero_motion_factor =
DEFAULT_ZM_FACTOR * (frame_stats->pcnt_inter - frame_stats->pcnt_motion);
// Clamp value to range 0.0 to 1.0
// This should happen anyway if input values are sensibly clamped but checked
// here just in case.
if (zero_motion_factor > 1.0)
zero_motion_factor = 1.0;
else if (zero_motion_factor < 0.0)
zero_motion_factor = 0.0;
return AOMMAX(zero_motion_factor,
(sr_decay_rate + ((1.0 - sr_decay_rate) * zero_motion_factor)));
}
// Function to test for a condition where a complex transition is followed
// by a static section. For example in slide shows where there is a fade
// between slides. This is to help with more optimal kf and gf positioning.
static int detect_transition_to_still(
const FIRSTPASS_INFO *firstpass_info,
int next_stats_index,
const int min_gf_interval,
const int frame_interval,
const int still_interval,
const double loop_decay_rate,
const double last_decay_rate) {
// Break clause to detect very still sections after motion
// For example a static image after a fade or other transition
// instead of a clean scene cut.
if (frame_interval > min_gf_interval && loop_decay_rate >= 0.999 &&
last_decay_rate < 0.9) {
int stats_left =
av1_firstpass_info_future_count(firstpass_info, next_stats_index);
if (stats_left >= still_interval) {
int j;
// Look ahead a few frames to see if static condition persists...
for (j = 0; j < still_interval; ++j) {
const FIRSTPASS_STATS *stats =
av1_firstpass_info_peek(firstpass_info, next_stats_index + j);
if (stats->pcnt_inter - stats->pcnt_motion < 0.999)
break;
}
// Only if it does do we signal a transition to still.
return j == still_interval;
}
}
return 0;
}
// This function detects a flash through the high relative pcnt_second_ref
// score in the frame following a flash frame. The offset passed in should
// reflect this.
static int detect_flash(
const TWO_PASS *twopass,
const TWO_PASS_FRAME *twopass_frame,
const int offset) {
const FIRSTPASS_STATS *
const next_frame =
read_frame_stats(twopass, twopass_frame, offset);
// What we are looking for here is a situation where there is a
// brief break in prediction (such as a flash) but subsequent frames
// are reasonably well predicted by an earlier (pre flash) frame.
// The recovery after a flash is indicated by a high pcnt_second_ref
// compared to pcnt_inter.
return next_frame != NULL &&
next_frame->pcnt_second_ref > next_frame->pcnt_inter &&
next_frame->pcnt_second_ref >= 0.5;
}
// Update the motion related elements to the GF arf boost calculation.
static void accumulate_frame_motion_stats(
const FIRSTPASS_STATS *stats,
GF_GROUP_STATS *gf_stats,
double f_w,
double f_h) {
const double pct = stats->pcnt_motion;
// Accumulate Motion In/Out of frame stats.
gf_stats->this_frame_mv_in_out = stats->mv_in_out_count * pct;
gf_stats->mv_in_out_accumulator += gf_stats->this_frame_mv_in_out;
gf_stats->abs_mv_in_out_accumulator += fabs(gf_stats->this_frame_mv_in_out);
// Accumulate a measure of how uniform (or conversely how random) the motion
// field is (a ratio of abs(mv) / mv).
if (pct > 0.05) {
const double mvr_ratio =
fabs(stats->mvr_abs) / DOUBLE_DIVIDE_CHECK(fabs(stats->MVr));
const double mvc_ratio =
fabs(stats->mvc_abs) / DOUBLE_DIVIDE_CHECK(fabs(stats->MVc));
gf_stats->mv_ratio_accumulator +=
pct *
(mvr_ratio < stats->mvr_abs * f_h ? mvr_ratio : stats->mvr_abs * f_h);
gf_stats->mv_ratio_accumulator +=
pct *
(mvc_ratio < stats->mvc_abs * f_w ? mvc_ratio : stats->mvc_abs * f_w);
}
}
static void accumulate_this_frame_stats(
const FIRSTPASS_STATS *stats,
const double mod_frame_err,
GF_GROUP_STATS *gf_stats) {
gf_stats->gf_group_err += mod_frame_err;
#if GROUP_ADAPTIVE_MAXQ
gf_stats->gf_group_raw_error += stats->coded_error;
#endif
gf_stats->gf_group_skip_pct += stats->intra_skip_pct;
gf_stats->gf_group_inactive_zone_rows += stats->inactive_zone_rows;
}
static void accumulate_next_frame_stats(
const FIRSTPASS_STATS *stats,
const int flash_detected,
const int frames_since_key,
const int cur_idx,
GF_GROUP_STATS *gf_stats,
int f_w,
int f_h) {
accumulate_frame_motion_stats(stats, gf_stats, f_w, f_h);
// sum up the metric values of current gf group
gf_stats->avg_sr_coded_error += stats->sr_coded_error;
gf_stats->avg_pcnt_second_ref += stats->pcnt_second_ref;
gf_stats->avg_new_mv_count += stats->new_mv_count;
gf_stats->avg_wavelet_energy += stats->frame_avg_wavelet_energy;
if (fabs(stats->raw_error_stdev) > 0.000001) {
gf_stats->non_zero_stdev_count++;
gf_stats->avg_raw_err_stdev += stats->raw_error_stdev;
}
// Accumulate the effect of prediction quality decay
if (!flash_detected) {
gf_stats->last_loop_decay_rate = gf_stats->loop_decay_rate;
gf_stats->loop_decay_rate = get_prediction_decay_rate(stats);
gf_stats->decay_accumulator =
gf_stats->decay_accumulator * gf_stats->loop_decay_rate;
// Monitor for static sections.
if ((frames_since_key + cur_idx - 1) > 1) {
gf_stats->zero_motion_accumulator = AOMMIN(
gf_stats->zero_motion_accumulator, get_zero_motion_factor(stats));
}
}
}
static void average_gf_stats(
const int total_frame, GF_GROUP_STATS *gf_stats) {
if (total_frame) {
gf_stats->avg_sr_coded_error /= total_frame;
gf_stats->avg_pcnt_second_ref /= total_frame;
gf_stats->avg_new_mv_count /= total_frame;
gf_stats->avg_wavelet_energy /= total_frame;
}
if (gf_stats->non_zero_stdev_count)
gf_stats->avg_raw_err_stdev /= gf_stats->non_zero_stdev_count;
}
#define BOOST_FACTOR 12.5
static double baseline_err_per_mb(
const FRAME_INFO *frame_info) {
unsigned int screen_area = frame_info->frame_height * frame_info->frame_width;
// Use a different error per mb factor for calculating boost for
// different formats.
if (screen_area <= 640 * 360) {
return 500.0;
}
else {
return 1000.0;
}
}
static double calc_frame_boost(
const PRIMARY_RATE_CONTROL *p_rc,
const FRAME_INFO *frame_info,
const FIRSTPASS_STATS *this_frame,
double this_frame_mv_in_out,
double max_boost) {
double frame_boost;
const double lq = av1_convert_qindex_to_q(p_rc->avg_frame_qindex[INTER_FRAME],
frame_info->bit_depth);
const double boost_q_correction = AOMMIN((0.5 + (lq * 0.015)), 1.5);
const double active_area = calculate_active_area(frame_info, this_frame);
// Underlying boost factor is based on inter error ratio.
frame_boost = AOMMAX(baseline_err_per_mb(frame_info) * active_area,
this_frame->intra_error * active_area) /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error);
frame_boost = frame_boost * BOOST_FACTOR * boost_q_correction;
// Increase boost for frames where new data coming into frame (e.g. zoom out).
// Slightly reduce boost if there is a net balance of motion out of the frame
// (zoom in). The range for this_frame_mv_in_out is -1.0 to +1.0.
if (this_frame_mv_in_out > 0.0)
frame_boost += frame_boost * (this_frame_mv_in_out * 2.0);
// In the extreme case the boost is halved.
else
frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
return AOMMIN(frame_boost, max_boost * boost_q_correction);
}
static double calc_kf_frame_boost(
const PRIMARY_RATE_CONTROL *p_rc,
const FRAME_INFO *frame_info,
const FIRSTPASS_STATS *this_frame,
double *sr_accumulator,
double max_boost) {
double frame_boost;
const double lq = av1_convert_qindex_to_q(p_rc->avg_frame_qindex[INTER_FRAME],
frame_info->bit_depth);
const double boost_q_correction = AOMMIN((0.50 + (lq * 0.015)), 2.00);
const double active_area = calculate_active_area(frame_info, this_frame);
// Underlying boost factor is based on inter error ratio.
frame_boost = AOMMAX(baseline_err_per_mb(frame_info) * active_area,
this_frame->intra_error * active_area) /
DOUBLE_DIVIDE_CHECK(
(this_frame->coded_error + *sr_accumulator) * active_area);
// Update the accumulator for second ref error difference.
// This is intended to give an indication of how much the coded error is
// increasing over time.
*sr_accumulator += (this_frame->sr_coded_error - this_frame->coded_error);
*sr_accumulator = AOMMAX(0.0, *sr_accumulator);
// Q correction and scaling
// The 40.0 value here is an experimentally derived baseline minimum.
// This value is in line with the minimum per frame boost in the alt_ref
// boost calculation.
frame_boost = ((frame_boost + 40.0) * boost_q_correction);
return AOMMIN(frame_boost, max_boost * boost_q_correction);
}
static int get_projected_gfu_boost(
const PRIMARY_RATE_CONTROL *p_rc,
int gfu_boost,
int frames_to_project,
int num_stats_used_for_gfu_boost) {
/*
* If frames_to_project is equal to num_stats_used_for_gfu_boost,
* it means that gfu_boost was calculated over frames_to_project to
* begin with(ie; all stats required were available), hence return
* the original boost.
*/
if (num_stats_used_for_gfu_boost >= frames_to_project)
return gfu_boost;
double min_boost_factor = sqrt(p_rc->baseline_gf_interval);
// Get the current tpl factor (number of frames = frames_to_project).
double tpl_factor = av1_get_gfu_boost_projection_factor(
min_boost_factor, MAX_GFUBOOST_FACTOR, frames_to_project);
// Get the tpl factor when number of frames = num_stats_used_for_prior_boost.
double tpl_factor_num_stats = av1_get_gfu_boost_projection_factor(
min_boost_factor, MAX_GFUBOOST_FACTOR, num_stats_used_for_gfu_boost);
int projected_gfu_boost =
(
int)rint((tpl_factor * gfu_boost) / tpl_factor_num_stats);
return projected_gfu_boost;
}
#define GF_MAX_BOOST 90.0
#define GF_MIN_BOOST 50
#define MIN_DECAY_FACTOR 0.01
int av1_calc_arf_boost(
const TWO_PASS *twopass,
const TWO_PASS_FRAME *twopass_frame,
const PRIMARY_RATE_CONTROL *p_rc, FRAME_INFO *frame_info,
int offset,
int f_frames,
int b_frames,
int *num_fpstats_used,
int *num_fpstats_required,
int project_gfu_boost) {
int i;
GF_GROUP_STATS gf_stats;
init_gf_stats(&gf_stats);
double boost_score = (
double)NORMAL_BOOST;
int arf_boost;
int flash_detected = 0;
if (num_fpstats_used) *num_fpstats_used = 0;
// Search forward from the proposed arf/next gf position.
for (i = 0; i < f_frames; ++i) {
const FIRSTPASS_STATS *this_frame =
read_frame_stats(twopass, twopass_frame, i + offset);
if (this_frame == NULL)
break;
// Update the motion related elements to the boost calculation.
accumulate_frame_motion_stats(this_frame, &gf_stats,
frame_info->frame_width,
frame_info->frame_height);
// We want to discount the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(twopass, twopass_frame, i + offset) ||
detect_flash(twopass, twopass_frame, i + offset + 1);
// Accumulate the effect of prediction quality decay.
if (!flash_detected) {
gf_stats.decay_accumulator *= get_prediction_decay_rate(this_frame);
gf_stats.decay_accumulator = gf_stats.decay_accumulator < MIN_DECAY_FACTOR
? MIN_DECAY_FACTOR
: gf_stats.decay_accumulator;
}
boost_score +=
gf_stats.decay_accumulator *
calc_frame_boost(p_rc, frame_info, this_frame,
gf_stats.this_frame_mv_in_out, GF_MAX_BOOST);
if (num_fpstats_used) (*num_fpstats_used)++;
}
arf_boost = (
int)boost_score;
// Reset for backward looking loop.
boost_score = 0.0;
init_gf_stats(&gf_stats);
// Search backward towards last gf position.
for (i = -1; i >= -b_frames; --i) {
const FIRSTPASS_STATS *this_frame =
read_frame_stats(twopass, twopass_frame, i + offset);
if (this_frame == NULL)
break;
// Update the motion related elements to the boost calculation.
accumulate_frame_motion_stats(this_frame, &gf_stats,
frame_info->frame_width,
frame_info->frame_height);
// We want to discount the the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(twopass, twopass_frame, i + offset) ||
detect_flash(twopass, twopass_frame, i + offset + 1);
// Cumulative effect of prediction quality decay.
if (!flash_detected) {
gf_stats.decay_accumulator *= get_prediction_decay_rate(this_frame);
gf_stats.decay_accumulator = gf_stats.decay_accumulator < MIN_DECAY_FACTOR
? MIN_DECAY_FACTOR
: gf_stats.decay_accumulator;
}
boost_score +=
gf_stats.decay_accumulator *
calc_frame_boost(p_rc, frame_info, this_frame,
gf_stats.this_frame_mv_in_out, GF_MAX_BOOST);
if (num_fpstats_used) (*num_fpstats_used)++;
}
arf_boost += (
int)boost_score;
if (project_gfu_boost) {
assert(num_fpstats_required != NULL);
assert(num_fpstats_used != NULL);
*num_fpstats_required = f_frames + b_frames;
arf_boost = get_projected_gfu_boost(p_rc, arf_boost, *num_fpstats_required,
*num_fpstats_used);
}
if (arf_boost < ((b_frames + f_frames) * GF_MIN_BOOST))
arf_boost = ((b_frames + f_frames) * GF_MIN_BOOST);
return arf_boost;
}
// Calculate a section intra ratio used in setting max loop filter.
static int calculate_section_intra_ratio(
const FIRSTPASS_STATS *begin,
const FIRSTPASS_STATS *end,
int section_length) {
const FIRSTPASS_STATS *s = begin;
double intra_error = 0.0;
double coded_error = 0.0;
int i = 0;
while (s < end && i < section_length) {
intra_error += s->intra_error;
coded_error += s->coded_error;
++s;
++i;
}
return (
int)(intra_error / DOUBLE_DIVIDE_CHECK(coded_error));
}
/*!\brief Calculates the bit target for this GF/ARF group
*
* \ingroup rate_control
*
* Calculates the total bits to allocate in this GF/ARF group.
*
* \param[in] cpi Top-level encoder structure
* \param[in] gf_group_err Cumulative coded error score for the
* frames making up this group.
*
* \return The target total number of bits for this GF/ARF group.
*/
static int64_t calculate_total_gf_group_bits(AV1_COMP *cpi,
double gf_group_err) {
const RATE_CONTROL *
const rc = &cpi->rc;
const PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const TWO_PASS *
const twopass = &cpi->ppi->twopass;
const int max_bits = frame_max_bits(rc, &cpi->oxcf);
int64_t total_group_bits;
// Calculate the bits to be allocated to the group as a whole.
if ((twopass->kf_group_bits > 0) && (twopass->kf_group_error_left > 0)) {
total_group_bits = (int64_t)(twopass->kf_group_bits *
(gf_group_err / twopass->kf_group_error_left));
}
else {
total_group_bits = 0;
}
// Clamp odd edge cases.
total_group_bits = (total_group_bits < 0) ? 0
: (total_group_bits > twopass->kf_group_bits)
? twopass->kf_group_bits
: total_group_bits;
// Clip based on user supplied data rate variability limit.
if (total_group_bits > (int64_t)max_bits * p_rc->baseline_gf_interval)
total_group_bits = (int64_t)max_bits * p_rc->baseline_gf_interval;
return total_group_bits;
}
// Calculate the number of bits to assign to boosted frames in a group.
static int calculate_boost_bits(
int frame_count,
int boost,
int64_t total_group_bits) {
int allocation_chunks;
// return 0 for invalid inputs (could arise e.g. through rounding errors)
if (!boost || (total_group_bits <= 0))
return 0;
if (frame_count <= 0)
return (
int)(AOMMIN(total_group_bits, INT_MAX));
allocation_chunks = (frame_count * 100) + boost;
// Prevent overflow.
if (boost > 1023) {
int divisor = boost >> 10;
boost /= divisor;
allocation_chunks /= divisor;
}
// Calculate the number of extra bits for use in the boosted frame or frames.
return AOMMAX((
int)(((int64_t)boost * total_group_bits) / allocation_chunks),
0);
}
// Calculate the boost factor based on the number of bits assigned, i.e. the
// inverse of calculate_boost_bits().
static int calculate_boost_factor(
int frame_count,
int bits,
int64_t total_group_bits) {
return (
int)(100.0 * frame_count * bits / (total_group_bits - bits));
}
// Reduce the number of bits assigned to keyframe or arf if necessary, to
// prevent bitrate spikes that may break level constraints.
// frame_type: 0: keyframe; 1: arf.
static int adjust_boost_bits_for_target_level(
const AV1_COMP *
const cpi,
RATE_CONTROL *
const rc,
int bits_assigned,
int64_t group_bits,
int frame_type) {
const AV1_COMMON *
const cm = &cpi->common;
const SequenceHeader *
const seq_params = cm->seq_params;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const int temporal_layer_id = cm->temporal_layer_id;
const int spatial_layer_id = cm->spatial_layer_id;
for (
int index = 0; index < seq_params->operating_points_cnt_minus_1 + 1;
++index) {
if (!is_in_operating_point(seq_params->operating_point_idc[index],
temporal_layer_id, spatial_layer_id)) {
continue;
}
const AV1_LEVEL target_level =
cpi->ppi->level_params.target_seq_level_idx[index];
if (target_level >= SEQ_LEVELS)
continue;
assert(is_valid_seq_level_idx(target_level));
const double level_bitrate_limit = av1_get_max_bitrate_for_level(
target_level, seq_params->tier[0], seq_params->profile);
const int target_bits_per_frame =
(
int)(level_bitrate_limit / cpi->framerate);
if (frame_type == 0) {
// Maximum bits for keyframe is 8 times the target_bits_per_frame.
const int level_enforced_max_kf_bits = target_bits_per_frame * 8;
if (bits_assigned > level_enforced_max_kf_bits) {
const int frames = rc->frames_to_key - 1;
p_rc->kf_boost = calculate_boost_factor(
frames, level_enforced_max_kf_bits, group_bits);
bits_assigned =
calculate_boost_bits(frames, p_rc->kf_boost, group_bits);
}
}
else if (frame_type == 1) {
// Maximum bits for arf is 4 times the target_bits_per_frame.
const int level_enforced_max_arf_bits = target_bits_per_frame * 4;
if (bits_assigned > level_enforced_max_arf_bits) {
p_rc->gfu_boost =
calculate_boost_factor(p_rc->baseline_gf_interval,
level_enforced_max_arf_bits, group_bits);
bits_assigned = calculate_boost_bits(p_rc->baseline_gf_interval,
p_rc->gfu_boost, group_bits);
}
}
else {
assert(0);
}
}
return bits_assigned;
}
// Allocate bits to each frame in a GF / ARF group
static void allocate_gf_group_bits(GF_GROUP *gf_group,
PRIMARY_RATE_CONTROL *
const p_rc,
RATE_CONTROL *
const rc,
int64_t gf_group_bits,
int gf_arf_bits,
int key_frame,
int use_arf) {
static const double layer_fraction[MAX_ARF_LAYERS + 1] = { 1.0, 0.70, 0.55,
0.60, 0.60, 1.0,
1.0 };
int64_t total_group_bits = gf_group_bits;
int base_frame_bits;
const int gf_group_size = gf_group->size;
int layer_frames[MAX_ARF_LAYERS + 1] = { 0 };
// For key frames the frame target rate is already set and it
// is also the golden frame.
// === [frame_index == 0] ===
int frame_index = !!key_frame;
// Subtract the extra bits set aside for ARF frames from the Group Total
if (use_arf) total_group_bits -= gf_arf_bits;
int num_frames =
AOMMAX(1, p_rc->baseline_gf_interval - (rc->frames_since_key == 0));
base_frame_bits = (
int)(total_group_bits / num_frames);
// Check the number of frames in each layer in case we have a
// non standard group length.
int max_arf_layer = gf_group->max_layer_depth - 1;
for (
int idx = frame_index; idx < gf_group_size; ++idx) {
if ((gf_group->update_type[idx] == ARF_UPDATE) ||
(gf_group->update_type[idx] == INTNL_ARF_UPDATE)) {
layer_frames[gf_group->layer_depth[idx]]++;
}
}
// Allocate extra bits to each ARF layer
int i;
int layer_extra_bits[MAX_ARF_LAYERS + 1] = { 0 };
assert(max_arf_layer <= MAX_ARF_LAYERS);
for (i = 1; i <= max_arf_layer; ++i) {
double fraction = (i == max_arf_layer) ? 1.0 : layer_fraction[i];
layer_extra_bits[i] =
(
int)((gf_arf_bits * fraction) / AOMMAX(1, layer_frames[i]));
gf_arf_bits -= (
int)(gf_arf_bits * fraction);
}
// Now combine ARF layer and baseline bits to give total bits for each frame.
int arf_extra_bits;
for (
int idx = frame_index; idx < gf_group_size; ++idx) {
switch (gf_group->update_type[idx]) {
case ARF_UPDATE:
case INTNL_ARF_UPDATE:
arf_extra_bits = layer_extra_bits[gf_group->layer_depth[idx]];
gf_group->bit_allocation[idx] =
(base_frame_bits > INT_MAX - arf_extra_bits)
? INT_MAX
: (base_frame_bits + arf_extra_bits);
break;
case INTNL_OVERLAY_UPDATE:
case OVERLAY_UPDATE: gf_group->bit_allocation[idx] = 0;
break;
default: gf_group->bit_allocation[idx] = base_frame_bits;
break;
}
}
// Set the frame following the current GOP to 0 bit allocation. For ARF
// groups, this next frame will be overlay frame, which is the first frame
// in the next GOP. For GF group, next GOP will overwrite the rate allocation.
// Setting this frame to use 0 bit (of out the current GOP budget) will
// simplify logics in reference frame management.
if (gf_group_size < MAX_STATIC_GF_GROUP_LENGTH)
gf_group->bit_allocation[gf_group_size] = 0;
}
// Returns true if KF group and GF group both are almost completely static.
static inline int is_almost_static(
double gf_zero_motion,
int kf_zero_motion,
int is_lap_enabled) {
if (is_lap_enabled) {
/*
* when LAP enabled kf_zero_motion is not reliable, so use strict
* constraint on gf_zero_motion.
*/
return (gf_zero_motion >= 0.999);
}
else {
return (gf_zero_motion >= 0.995) &&
(kf_zero_motion >= STATIC_KF_GROUP_THRESH);
}
}
#define ARF_ABS_ZOOM_THRESH 4.4
static inline int detect_gf_cut(AV1_COMP *cpi,
int frame_index,
int cur_start,
int flash_detected,
int active_max_gf_interval,
int active_min_gf_interval,
GF_GROUP_STATS *gf_stats) {
RATE_CONTROL *
const rc = &cpi->rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
AV1_COMMON *
const cm = &cpi->common;
// Motion breakout threshold for loop below depends on image size.
const double mv_ratio_accumulator_thresh = (cm->height + cm->width) / 4.0;
if (!flash_detected) {
// Break clause to detect very still sections after motion. For example,
// a static image after a fade or other transition.
// TODO(angiebird): This is a temporary change, we will avoid using
// twopass_frame.stats_in in the follow-up CL
int index = (
int)(cpi->twopass_frame.stats_in -
twopass->stats_buf_ctx->stats_in_start);
if (detect_transition_to_still(&twopass->firstpass_info, index,
rc->min_gf_interval, frame_index - cur_start,
5, gf_stats->loop_decay_rate,
gf_stats->last_loop_decay_rate)) {
return 1;
}
}
// Some conditions to breakout after min interval.
if (frame_index - cur_start >= active_min_gf_interval &&
// If possible don't break very close to a kf
(rc->frames_to_key - frame_index >= rc->min_gf_interval) &&
((frame_index - cur_start) & 0x01) && !flash_detected &&
(gf_stats->mv_ratio_accumulator > mv_ratio_accumulator_thresh ||
gf_stats->abs_mv_in_out_accumulator > ARF_ABS_ZOOM_THRESH)) {
return 1;
}
// If almost totally static, we will not use the the max GF length later,
// so we can continue for more frames.
if (((frame_index - cur_start) >= active_max_gf_interval + 1) &&
!is_almost_static(gf_stats->zero_motion_accumulator,
twopass->kf_zeromotion_pct, cpi->ppi->lap_enabled)) {
return 1;
}
return 0;
}
static int is_shorter_gf_interval_better(
AV1_COMP *cpi,
const EncodeFrameParams *frame_params) {
const RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
int gop_length_decision_method = cpi->sf.tpl_sf.gop_length_decision_method;
int shorten_gf_interval;
av1_tpl_preload_rc_estimate(cpi, frame_params);
if (gop_length_decision_method == 2) {
// GF group length is decided based on GF boost and tpl stats of ARFs from
// base layer, (base+1) layer.
shorten_gf_interval =
(p_rc->gfu_boost <
p_rc->num_stats_used_for_gfu_boost * GF_MIN_BOOST * 1.4) &&
!av1_tpl_setup_stats(cpi, 3, frame_params);
}
else {
int do_complete_tpl = 1;
GF_GROUP *
const gf_group = &cpi->ppi->gf_group;
int is_temporal_filter_enabled =
(rc->frames_since_key > 0 && gf_group->arf_index > -1);
if (gop_length_decision_method == 1) {
// Check if tpl stats of ARFs from base layer, (base+1) layer,
// (base+2) layer can decide the GF group length.
int gop_length_eval = av1_tpl_setup_stats(cpi, 2, frame_params);
if (gop_length_eval != 2) {
do_complete_tpl = 0;
shorten_gf_interval = !gop_length_eval;
}
}
if (do_complete_tpl) {
// Decide GF group length based on complete tpl stats.
shorten_gf_interval = !av1_tpl_setup_stats(cpi, 1, frame_params);
// Tpl stats is reused when the ARF is temporally filtered and GF
// interval is not shortened.
if (is_temporal_filter_enabled && !shorten_gf_interval) {
cpi->skip_tpl_setup_stats = 1;
#if CONFIG_BITRATE_ACCURACY && !CONFIG_THREE_PASS
assert(cpi->gf_frame_index == 0);
av1_vbr_rc_update_q_index_list(&cpi->vbr_rc_info, &cpi->ppi->tpl_data,
gf_group,
cpi->common.seq_params->bit_depth);
#endif // CONFIG_BITRATE_ACCURACY
}
}
}
return shorten_gf_interval;
}
#define MIN_SHRINK_LEN 6
// the minimum length of gf if we are shrinking
#define SMOOTH_FILT_LEN 7
#define HALF_FILT_LEN (SMOOTH_FILT_LEN / 2)
#define WINDOW_SIZE 7
#define HALF_WIN (WINDOW_SIZE / 2)
// Smooth filter intra_error and coded_error in firstpass stats.
// If stats[i].is_flash==1, the ith element should not be used in the filtering.
static void smooth_filter_stats(
const FIRSTPASS_STATS *stats,
int start_idx,
int last_idx,
double *filt_intra_err,
double *filt_coded_err) {
// A 7-tap gaussian smooth filter
static const double smooth_filt[SMOOTH_FILT_LEN] = { 0.006, 0.061, 0.242,
0.383, 0.242, 0.061,
0.006 };
int i, j;
for (i = start_idx; i <= last_idx; i++) {
double total_wt = 0;
for (j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) {
int idx = AOMMIN(AOMMAX(i + j, start_idx), last_idx);
if (stats[idx].is_flash)
continue;
filt_intra_err[i] +=
smooth_filt[j + HALF_FILT_LEN] * stats[idx].intra_error;
total_wt += smooth_filt[j + HALF_FILT_LEN];
}
if (total_wt > 0.01) {
filt_intra_err[i] /= total_wt;
}
else {
filt_intra_err[i] = stats[i].intra_error;
}
}
for (i = start_idx; i <= last_idx; i++) {
double total_wt = 0;
for (j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) {
int idx = AOMMIN(AOMMAX(i + j, start_idx), last_idx);
// Coded error involves idx and idx - 1.
if (stats[idx].is_flash || (idx > 0 && stats[idx - 1].is_flash))
continue;
filt_coded_err[i] +=
smooth_filt[j + HALF_FILT_LEN] * stats[idx].coded_error;
total_wt += smooth_filt[j + HALF_FILT_LEN];
}
if (total_wt > 0.01) {
filt_coded_err[i] /= total_wt;
}
else {
filt_coded_err[i] = stats[i].coded_error;
}
}
}
// Calculate gradient
static void get_gradient(
const double *values,
int start,
int last,
double *grad) {
if (start == last) {
grad[start] = 0;
return;
}
for (
int i = start; i <= last; i++) {
int prev = AOMMAX(i - 1, start);
int next = AOMMIN(i + 1, last);
grad[i] = (values[next] - values[prev]) / (next - prev);
}
}
static int find_next_scenecut(
const FIRSTPASS_STATS *
const stats_start,
int first,
int last) {
// Identify unstable areas caused by scenecuts.
// Find the max and 2nd max coded error, and the average of the rest frames.
// If there is only one frame that yields a huge coded error, it is likely a
// scenecut.
double this_ratio, max_prev_ratio, max_next_ratio, max_prev_coded,
max_next_coded;
if (last - first == 0)
return -1;
for (
int i = first; i <= last; i++) {
if (stats_start[i].is_flash || (i > 0 && stats_start[i - 1].is_flash))
continue;
double temp_intra = AOMMAX(stats_start[i].intra_error, 0.01);
this_ratio = stats_start[i].coded_error / temp_intra;
// find the avg ratio in the preceding neighborhood
max_prev_ratio = 0;
max_prev_coded = 0;
for (
int j = AOMMAX(first, i - HALF_WIN); j < i; j++) {
if (stats_start[j].is_flash || (j > 0 && stats_start[j - 1].is_flash))
continue;
temp_intra = AOMMAX(stats_start[j].intra_error, 0.01);
double temp_ratio = stats_start[j].coded_error / temp_intra;
if (temp_ratio > max_prev_ratio) {
max_prev_ratio = temp_ratio;
}
if (stats_start[j].coded_error > max_prev_coded) {
max_prev_coded = stats_start[j].coded_error;
}
}
// find the avg ratio in the following neighborhood
max_next_ratio = 0;
max_next_coded = 0;
for (
int j = i + 1; j <= AOMMIN(i + HALF_WIN, last); j++) {
if (stats_start[i].is_flash || (i > 0 && stats_start[i - 1].is_flash))
continue;
temp_intra = AOMMAX(stats_start[j].intra_error, 0.01);
double temp_ratio = stats_start[j].coded_error / temp_intra;
if (temp_ratio > max_next_ratio) {
max_next_ratio = temp_ratio;
}
if (stats_start[j].coded_error > max_next_coded) {
max_next_coded = stats_start[j].coded_error;
}
}
if (max_prev_ratio < 0.001 && max_next_ratio < 0.001) {
// the ratios are very small, only check a small fixed threshold
if (this_ratio < 0.02)
continue;
}
else {
// check if this frame has a larger ratio than the neighborhood
double max_sr = stats_start[i].sr_coded_error;
if (i < last) max_sr = AOMMAX(max_sr, stats_start[i + 1].sr_coded_error);
double max_sr_fr_ratio =
max_sr / AOMMAX(stats_start[i].coded_error, 0.01);
if (max_sr_fr_ratio > 1.2)
continue;
if (this_ratio < 2 * AOMMAX(max_prev_ratio, max_next_ratio) &&
stats_start[i].coded_error <
2 * AOMMAX(max_prev_coded, max_next_coded)) {
continue;
}
}
return i;
}
return -1;
}
// Remove the region with index next_region.
// parameter merge: 0: merge with previous; 1: merge with next; 2:
// merge with both, take type from previous if possible
// After removing, next_region will be the index of the next region.
static void remove_region(
int merge, REGIONS *regions,
int *num_regions,
int *next_region) {
int k = *next_region;
assert(k < *num_regions);
if (*num_regions == 1) {
*num_regions = 0;
return;
}
if (k == 0) {
merge = 1;
}
else if (k == *num_regions - 1) {
merge = 0;
}
int num_merge = (merge == 2) ? 2 : 1;
switch (merge) {
case 0:
regions[k - 1].last = regions[k].last;
*next_region = k;
break;
case 1:
regions[k + 1].start = regions[k].start;
*next_region = k + 1;
break;
case 2:
regions[k - 1].last = regions[k + 1].last;
*next_region = k;
break;
default: assert(0);
}
*num_regions -= num_merge;
for (k = *next_region - (merge == 1); k < *num_regions; k++) {
regions[k] = regions[k + num_merge];
}
}
// Insert a region in the cur_region_idx. The start and last should both be in
// the current region. After insertion, the cur_region_idx will point to the
// last region that was splitted from the original region.
static void insert_region(
int start,
int last, REGION_TYPES type,
REGIONS *regions,
int *num_regions,
int *cur_region_idx) {
int k = *cur_region_idx;
REGION_TYPES this_region_type = regions[k].type;
int this_region_last = regions[k].last;
int num_add = (start != regions[k].start) + (last != regions[k].last);
// move the following regions further to the back
for (
int r = *num_regions - 1; r > k; r--) {
regions[r + num_add] = regions[r];
}
*num_regions += num_add;
if (start > regions[k].start) {
regions[k].last = start - 1;
k++;
regions[k].start = start;
}
regions[k].type = type;
if (last < this_region_last) {
regions[k].last = last;
k++;
regions[k].start = last + 1;
regions[k].last = this_region_last;
regions[k].type = this_region_type;
}
else {
regions[k].last = this_region_last;
}
*cur_region_idx = k;
}
// Get the average of stats inside a region.
static void analyze_region(
const FIRSTPASS_STATS *stats,
int k,
REGIONS *regions) {
int i;
regions[k].avg_cor_coeff = 0;
regions[k].avg_sr_fr_ratio = 0;
regions[k].avg_intra_err = 0;
regions[k].avg_coded_err = 0;
int check_first_sr = (k != 0);
for (i = regions[k].start; i <= regions[k].last; i++) {
if (i > regions[k].start || check_first_sr) {
double num_frames =
(
double)(regions[k].last - regions[k].start + check_first_sr);
double max_coded_error =
AOMMAX(stats[i].coded_error, stats[i - 1].coded_error);
double this_ratio =
stats[i].sr_coded_error / AOMMAX(max_coded_error, 0.001);
regions[k].avg_sr_fr_ratio += this_ratio / num_frames;
}
regions[k].avg_intra_err +=
stats[i].intra_error / (
double)(regions[k].last - regions[k].start + 1);
regions[k].avg_coded_err +=
stats[i].coded_error / (
double)(regions[k].last - regions[k].start + 1);
regions[k].avg_cor_coeff +=
AOMMAX(stats[i].cor_coeff, 0.001) /
(
double)(regions[k].last - regions[k].start + 1);
regions[k].avg_noise_var +=
AOMMAX(stats[i].noise_var, 0.001) /
(
double)(regions[k].last - regions[k].start + 1);
}
}
// Calculate the regions stats of every region.
static void get_region_stats(
const FIRSTPASS_STATS *stats, REGIONS *regions,
int num_regions) {
for (
int k = 0; k < num_regions; k++) {
analyze_region(stats, k, regions);
}
}
// Find tentative stable regions
static int find_stable_regions(
const FIRSTPASS_STATS *stats,
const double *grad_coded,
int this_start,
int this_last, REGIONS *regions) {
int i, j, k = 0;
regions[k].start = this_start;
for (i = this_start; i <= this_last; i++) {
// Check mean and variance of stats in a window
double mean_intra = 0.001, var_intra = 0.001;
double mean_coded = 0.001, var_coded = 0.001;
int count = 0;
for (j = -HALF_WIN; j <= HALF_WIN; j++) {
int idx = AOMMIN(AOMMAX(i + j, this_start), this_last);
if (stats[idx].is_flash || (idx > 0 && stats[idx - 1].is_flash))
continue;
mean_intra += stats[idx].intra_error;
var_intra += stats[idx].intra_error * stats[idx].intra_error;
mean_coded += stats[idx].coded_error;
var_coded += stats[idx].coded_error * stats[idx].coded_error;
count++;
}
REGION_TYPES cur_type;
if (count > 0) {
mean_intra /= (
double)count;
var_intra /= (
double)count;
mean_coded /= (
double)count;
var_coded /= (
double)count;
int is_intra_stable = (var_intra / (mean_intra * mean_intra) < 1.03);
int is_coded_stable = (var_coded / (mean_coded * mean_coded) < 1.04 &&
fabs(grad_coded[i]) / mean_coded < 0.05) ||
mean_coded / mean_intra < 0.05;
int is_coded_small = mean_coded < 0.5 * mean_intra;
cur_type = (is_intra_stable && is_coded_stable && is_coded_small)
? STABLE_REGION
: HIGH_VAR_REGION;
}
else {
cur_type = HIGH_VAR_REGION;
}
// mark a new region if type changes
if (i == regions[k].start) {
// first frame in the region
regions[k].type = cur_type;
}
else if (cur_type != regions[k].type) {
// Append a new region
regions[k].last = i - 1;
regions[k + 1].start = i;
regions[k + 1].type = cur_type;
k++;
}
}
regions[k].last = this_last;
return k + 1;
}
// Clean up regions that should be removed or merged.
static void cleanup_regions(REGIONS *regions,
int *num_regions) {
int k = 0;
while (k < *num_regions) {
if ((k > 0 && regions[k - 1].type == regions[k].type &&
regions[k].type != SCENECUT_REGION) ||
regions[k].last < regions[k].start) {
remove_region(0, regions, num_regions, &k);
}
else {
k++;
}
}
}
// Remove regions that are of type and shorter than length.
// Merge it with its neighboring regions.
static void remove_short_regions(REGIONS *regions,
int *num_regions,
REGION_TYPES type,
int length) {
int k = 0;
while (k < *num_regions && (*num_regions) > 1) {
if ((regions[k].last - regions[k].start + 1 < length &&
regions[k].type == type)) {
// merge current region with the previous and next regions
remove_region(2, regions, num_regions, &k);
}
else {
k++;
}
}
cleanup_regions(regions, num_regions);
}
static void adjust_unstable_region_bounds(
const FIRSTPASS_STATS *stats,
REGIONS *regions,
int *num_regions) {
int i, j, k;
// Remove regions that are too short. Likely noise.
remove_short_regions(regions, num_regions, STABLE_REGION, HALF_WIN);
remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN);
get_region_stats(stats, regions, *num_regions);
// Adjust region boundaries. The thresholds are empirically obtained, but
// overall the performance is not very sensitive to small changes to them.
for (k = 0; k < *num_regions; k++) {
if (regions[k].type == STABLE_REGION)
continue;
if (k > 0) {
// Adjust previous boundary.
// First find the average intra/coded error in the previous
// neighborhood.
double avg_intra_err = 0;
const int starti = AOMMAX(regions[k - 1].last - WINDOW_SIZE + 1,
regions[k - 1].start + 1);
const int lasti = regions[k - 1].last;
int counti = 0;
for (i = starti; i <= lasti; i++) {
avg_intra_err += stats[i].intra_error;
counti++;
}
if (counti > 0) {
avg_intra_err = AOMMAX(avg_intra_err / (
double)counti, 0.001);
int count_coded = 0, count_grad = 0;
for (j = lasti + 1; j <= regions[k].last; j++) {
const int intra_close =
fabs(stats[j].intra_error - avg_intra_err) / avg_intra_err < 0.1;
const int coded_small = stats[j].coded_error / avg_intra_err < 0.1;
const int coeff_close = stats[j].cor_coeff > 0.995;
if (!coeff_close || !coded_small) count_coded--;
if (intra_close && count_coded >= 0 && count_grad >= 0) {
// this frame probably belongs to the previous stable region
regions[k - 1].last = j;
regions[k].start = j + 1;
}
else {
break;
}
}
}
}
// if k > 0
if (k < *num_regions - 1) {
// Adjust next boundary.
// First find the average intra/coded error in the next neighborhood.
double avg_intra_err = 0;
const int starti = regions[k + 1].start;
const int lasti = AOMMIN(regions[k + 1].last - 1,
regions[k + 1].start + WINDOW_SIZE - 1);
int counti = 0;
for (i = starti; i <= lasti; i++) {
avg_intra_err += stats[i].intra_error;
counti++;
}
if (counti > 0) {
avg_intra_err = AOMMAX(avg_intra_err / (
double)counti, 0.001);
// At the boundary, coded error is large, but still the frame is stable
int count_coded = 1, count_grad = 1;
for (j = starti - 1; j >= regions[k].start; j--) {
const int intra_close =
fabs(stats[j].intra_error - avg_intra_err) / avg_intra_err < 0.1;
const int coded_small =
stats[j + 1].coded_error / avg_intra_err < 0.1;
const int coeff_close = stats[j].cor_coeff > 0.995;
if (!coeff_close || !coded_small) count_coded--;
if (intra_close && count_coded >= 0 && count_grad >= 0) {
// this frame probably belongs to the next stable region
regions[k + 1].start = j;
regions[k].last = j - 1;
}
else {
break;
}
}
}
}
// if k < *num_regions - 1
}
// end of loop over all regions
cleanup_regions(regions, num_regions);
remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN);
get_region_stats(stats, regions, *num_regions);
// If a stable regions has higher error than neighboring high var regions,
// or if the stable region has a lower average correlation,
// then it should be merged with them
k = 0;
while (k < *num_regions && (*num_regions) > 1) {
if (regions[k].type == STABLE_REGION &&
(regions[k].last - regions[k].start + 1) < 2 * WINDOW_SIZE &&
((k > 0 &&
// previous regions
(regions[k].avg_coded_err > regions[k - 1].avg_coded_err * 1.01 ||
regions[k].avg_cor_coeff < regions[k - 1].avg_cor_coeff * 0.999)) &&
(k < *num_regions - 1 &&
// next region
(regions[k].avg_coded_err > regions[k + 1].avg_coded_err * 1.01 ||
regions[k].avg_cor_coeff < regions[k + 1].avg_cor_coeff * 0.999)))) {
// merge current region with the previous and next regions
remove_region(2, regions, num_regions, &k);
analyze_region(stats, k - 1, regions);
}
else if (regions[k].type == HIGH_VAR_REGION &&
(regions[k].last - regions[k].start + 1) < 2 * WINDOW_SIZE &&
((k > 0 &&
// previous regions
(regions[k].avg_coded_err <
regions[k - 1].avg_coded_err * 0.99 ||
regions[k].avg_cor_coeff >
regions[k - 1].avg_cor_coeff * 1.001)) &&
(k < *num_regions - 1 &&
// next region
(regions[k].avg_coded_err <
regions[k + 1].avg_coded_err * 0.99 ||
regions[k].avg_cor_coeff >
regions[k + 1].avg_cor_coeff * 1.001)))) {
// merge current region with the previous and next regions
remove_region(2, regions, num_regions, &k);
analyze_region(stats, k - 1, regions);
}
else {
k++;
}
}
remove_short_regions(regions, num_regions, STABLE_REGION, WINDOW_SIZE);
remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN);
}
// Identify blending regions.
static void find_blending_regions(
const FIRSTPASS_STATS *stats,
REGIONS *regions,
int *num_regions) {
int i, k = 0;
// Blending regions will have large content change, therefore will have a
// large consistent change in intra error.
int count_stable = 0;
while (k < *num_regions) {
if (regions[k].type == STABLE_REGION) {
k++;
count_stable++;
continue;
}
int dir = 0;
int start = 0, last;
for (i = regions[k].start; i <= regions[k].last; i++) {
// First mark the regions that has consistent large change of intra error.
if (k == 0 && i == regions[k].start)
continue;
if (stats[i].is_flash || (i > 0 && stats[i - 1].is_flash))
continue;
double grad = stats[i].intra_error - stats[i - 1].intra_error;
int large_change = fabs(grad) / AOMMAX(stats[i].intra_error, 0.01) > 0.05;
int this_dir = 0;
if (large_change) {
this_dir = (grad > 0) ? 1 : -1;
}
// the current trend continues
if (dir == this_dir)
continue;
if (dir != 0) {
// Mark the end of a new large change group and add it
last = i - 1;
insert_region(start, last, BLENDING_REGION, regions, num_regions, &k);
}
dir = this_dir;
if (k == 0 && i == regions[k].start + 1) {
start = i - 1;
}
else {
start = i;
}
}
if (dir != 0) {
last = regions[k].last;
insert_region(start, last, BLENDING_REGION, regions, num_regions, &k);
}
k++;
}
// If the blending region has very low correlation, mark it as high variance
// since we probably cannot benefit from it anyways.
get_region_stats(stats, regions, *num_regions);
for (k = 0; k < *num_regions; k++) {
if (regions[k].type != BLENDING_REGION)
continue;
if (regions[k].last == regions[k].start || regions[k].avg_cor_coeff < 0.6 ||
count_stable == 0)
regions[k].type = HIGH_VAR_REGION;
}
get_region_stats(stats, regions, *num_regions);
// It is possible for blending to result in a "dip" in intra error (first
// decrease then increase). Therefore we need to find the dip and combine the
// two regions.
k = 1;
while (k < *num_regions) {
if (k < *num_regions - 1 && regions[k].type == HIGH_VAR_REGION) {
// Check if this short high variance regions is actually in the middle of
// a blending region.
if (regions[k - 1].type == BLENDING_REGION &&
regions[k + 1].type == BLENDING_REGION &&
regions[k].last - regions[k].start < 3) {
int prev_dir = (stats[regions[k - 1].last].intra_error -
stats[regions[k - 1].last - 1].intra_error) > 0
? 1
: -1;
int next_dir = (stats[regions[k + 1].last].intra_error -
stats[regions[k + 1].last - 1].intra_error) > 0
? 1
: -1;
if (prev_dir < 0 && next_dir > 0) {
// This is possibly a mid region of blending. Check the ratios
double ratio_thres = AOMMIN(regions[k - 1].avg_sr_fr_ratio,
regions[k + 1].avg_sr_fr_ratio) *
0.95;
if (regions[k].avg_sr_fr_ratio > ratio_thres) {
regions[k].type = BLENDING_REGION;
remove_region(2, regions, num_regions, &k);
analyze_region(stats, k - 1, regions);
continue;
}
}
}
}
// Check if we have a pair of consecutive blending regions.
if (regions[k - 1].type == BLENDING_REGION &&
regions[k].type == BLENDING_REGION) {
int prev_dir = (stats[regions[k - 1].last].intra_error -
stats[regions[k - 1].last - 1].intra_error) > 0
? 1
: -1;
int next_dir = (stats[regions[k].last].intra_error -
stats[regions[k].last - 1].intra_error) > 0
? 1
: -1;
// if both are too short, no need to check
int total_length = regions[k].last - regions[k - 1].start + 1;
if (total_length < 4) {
regions[k - 1].type = HIGH_VAR_REGION;
k++;
continue;
}
int to_merge = 0;
if (prev_dir < 0 && next_dir > 0) {
// In this case we check the last frame in the previous region.
double prev_length =
(
double)(regions[k - 1].last - regions[k - 1].start + 1);
double last_ratio, ratio_thres;
if (prev_length < 2.01) {
// if the previous region is very short
double max_coded_error =
AOMMAX(stats[regions[k - 1].last].coded_error,
stats[regions[k - 1].last - 1].coded_error);
last_ratio = stats[regions[k - 1].last].sr_coded_error /
AOMMAX(max_coded_error, 0.001);
ratio_thres = regions[k].avg_sr_fr_ratio * 0.95;
}
else {
double max_coded_error =
AOMMAX(stats[regions[k - 1].last].coded_error,
stats[regions[k - 1].last - 1].coded_error);
last_ratio = stats[regions[k - 1].last].sr_coded_error /
AOMMAX(max_coded_error, 0.001);
double prev_ratio =
(regions[k - 1].avg_sr_fr_ratio * prev_length - last_ratio) /
(prev_length - 1.0);
ratio_thres = AOMMIN(prev_ratio, regions[k].avg_sr_fr_ratio) * 0.95;
}
if (last_ratio > ratio_thres) {
to_merge = 1;
}
}
if (to_merge) {
remove_region(0, regions, num_regions, &k);
analyze_region(stats, k - 1, regions);
continue;
}
else {
// These are possibly two separate blending regions. Mark the boundary
// frame as HIGH_VAR_REGION to separate the two.
int prev_k = k - 1;
insert_region(regions[prev_k].last, regions[prev_k].last,
HIGH_VAR_REGION, regions, num_regions, &prev_k);
analyze_region(stats, prev_k, regions);
k = prev_k + 1;
analyze_region(stats, k, regions);
}
}
k++;
}
cleanup_regions(regions, num_regions);
}
// Clean up decision for blendings. Remove blending regions that are too short.
// Also if a very short high var region is between a blending and a stable
// region, just merge it with one of them.
static void cleanup_blendings(REGIONS *regions,
int *num_regions) {
int k = 0;
while (k<*num_regions && * num_regions> 1) {
int is_short_blending = regions[k].type == BLENDING_REGION &&
regions[k].last - regions[k].start + 1 < 5;
int is_short_hv = regions[k].type == HIGH_VAR_REGION &&
regions[k].last - regions[k].start + 1 < 5;
int has_stable_neighbor =
((k > 0 && regions[k - 1].type == STABLE_REGION) ||
(k < *num_regions - 1 && regions[k + 1].type == STABLE_REGION));
int has_blend_neighbor =
((k > 0 && regions[k - 1].type == BLENDING_REGION) ||
(k < *num_regions - 1 && regions[k + 1].type == BLENDING_REGION));
int total_neighbors = (k > 0) + (k < *num_regions - 1);
if (is_short_blending ||
(is_short_hv &&
has_stable_neighbor + has_blend_neighbor >= total_neighbors)) {
// Remove this region.Try to determine whether to combine it with the
// previous or next region.
int merge;
double prev_diff =
(k > 0)
? fabs(regions[k].avg_cor_coeff - regions[k - 1].avg_cor_coeff)
: 1;
double next_diff =
(k < *num_regions - 1)
? fabs(regions[k].avg_cor_coeff - regions[k + 1].avg_cor_coeff)
: 1;
// merge == 0 means to merge with previous, 1 means to merge with next
merge = prev_diff > next_diff;
remove_region(merge, regions, num_regions, &k);
}
else {
k++;
}
}
cleanup_regions(regions, num_regions);
}
static void free_firstpass_stats_buffers(REGIONS *temp_regions,
double *filt_intra_err,
double *filt_coded_err,
double *grad_coded) {
aom_free(temp_regions);
aom_free(filt_intra_err);
aom_free(filt_coded_err);
aom_free(grad_coded);
}
// Identify stable and unstable regions from first pass stats.
// stats_start points to the first frame to analyze.
// |offset| is the offset from the current frame to the frame stats_start is
// pointing to.
// Returns 0 on success, -1 on memory allocation failure.
static int identify_regions(
const FIRSTPASS_STATS *
const stats_start,
int total_frames,
int offset, REGIONS *regions,
int *total_regions) {
int k;
if (total_frames <= 1)
return 0;
// store the initial decisions
REGIONS *temp_regions =
(REGIONS *)aom_malloc(total_frames *
sizeof(temp_regions[0]));
// buffers for filtered stats
double *filt_intra_err =
(
double *)aom_calloc(total_frames,
sizeof(*filt_intra_err));
double *filt_coded_err =
(
double *)aom_calloc(total_frames,
sizeof(*filt_coded_err));
double *grad_coded = (
double *)aom_calloc(total_frames,
sizeof(*grad_coded));
if (!(temp_regions && filt_intra_err && filt_coded_err && grad_coded)) {
free_firstpass_stats_buffers(temp_regions, filt_intra_err, filt_coded_err,
grad_coded);
return -1;
}
av1_zero_array(temp_regions, total_frames);
int cur_region = 0, this_start = 0, this_last;
int next_scenecut = -1;
do {
// first get the obvious scenecuts
next_scenecut =
find_next_scenecut(stats_start, this_start, total_frames - 1);
this_last = (next_scenecut >= 0) ? (next_scenecut - 1) : total_frames - 1;
// low-pass filter the needed stats
smooth_filter_stats(stats_start, this_start, this_last, filt_intra_err,
filt_coded_err);
get_gradient(filt_coded_err, this_start, this_last, grad_coded);
// find tentative stable regions and unstable regions
int num_regions = find_stable_regions(stats_start, grad_coded, this_start,
this_last, temp_regions);
adjust_unstable_region_bounds(stats_start, temp_regions, &num_regions);
get_region_stats(stats_start, temp_regions, num_regions);
// Try to identify blending regions in the unstable regions
find_blending_regions(stats_start, temp_regions, &num_regions);
cleanup_blendings(temp_regions, &num_regions);
// The flash points should all be considered high variance points
k = 0;
while (k < num_regions) {
if (temp_regions[k].type != STABLE_REGION) {
k++;
continue;
}
int start = temp_regions[k].start;
int last = temp_regions[k].last;
for (
int i = start; i <= last; i++) {
if (stats_start[i].is_flash) {
insert_region(i, i, HIGH_VAR_REGION, temp_regions, &num_regions, &k);
}
}
k++;
}
cleanup_regions(temp_regions, &num_regions);
// copy the regions in the scenecut group
for (k = 0; k < num_regions; k++) {
if (temp_regions[k].last < temp_regions[k].start &&
k == num_regions - 1) {
num_regions--;
break;
}
regions[k + cur_region] = temp_regions[k];
}
cur_region += num_regions;
// add the scenecut region
if (next_scenecut > -1) {
// add the scenecut region, and find the next scenecut
regions[cur_region].type = SCENECUT_REGION;
regions[cur_region].start = next_scenecut;
regions[cur_region].last = next_scenecut;
cur_region++;
this_start = next_scenecut + 1;
}
}
while (next_scenecut >= 0);
*total_regions = cur_region;
get_region_stats(stats_start, regions, *total_regions);
for (k = 0; k < *total_regions; k++) {
// If scenecuts are very minor, mark them as high variance.
if (regions[k].type != SCENECUT_REGION ||
regions[k].avg_cor_coeff *
(1 - stats_start[regions[k].start].noise_var /
regions[k].avg_intra_err) <
0.8) {
continue;
}
regions[k].type = HIGH_VAR_REGION;
}
cleanup_regions(regions, total_regions);
get_region_stats(stats_start, regions, *total_regions);
for (k = 0; k < *total_regions; k++) {
regions[k].start += offset;
regions[k].last += offset;
}
free_firstpass_stats_buffers(temp_regions, filt_intra_err, filt_coded_err,
grad_coded);
return 0;
}
static int find_regions_index(
const REGIONS *regions,
int num_regions,
int frame_idx) {
for (
int k = 0; k < num_regions; k++) {
if (regions[k].start <= frame_idx && regions[k].last >= frame_idx) {
return k;
}
}
return -1;
}
/*!\brief Determine the length of future GF groups.
*
* \ingroup gf_group_algo
* This function decides the gf group length of future frames in batch
*
* \param[in] cpi Top-level encoder structure
* \param[in] max_gop_length Maximum length of the GF group
* \param[in] max_intervals Maximum number of intervals to decide
*
* \remark Nothing is returned. Instead, cpi->ppi->rc.gf_intervals is
* changed to store the decided GF group lengths.
*/
static void calculate_gf_length(AV1_COMP *cpi,
int max_gop_length,
int max_intervals) {
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FIRSTPASS_STATS next_frame;
const FIRSTPASS_STATS *
const start_pos = cpi->twopass_frame.stats_in;
const FIRSTPASS_STATS *
const stats = start_pos - (rc->frames_since_key == 0);
const int f_w = cpi->common.width;
const int f_h = cpi->common.height;
int i;
int flash_detected;
av1_zero(next_frame);
if (has_no_stats_stage(cpi)) {
for (i = 0; i < MAX_NUM_GF_INTERVALS; i++) {
p_rc->gf_intervals[i] = AOMMIN(rc->max_gf_interval, max_gop_length);
}
p_rc->cur_gf_index = 0;
rc->intervals_till_gf_calculate_due = MAX_NUM_GF_INTERVALS;
return;
}
// TODO(urvang): Try logic to vary min and max interval based on q.
const int active_min_gf_interval = rc->min_gf_interval;
const int active_max_gf_interval =
AOMMIN(rc->max_gf_interval, max_gop_length);
const int min_shrink_int = AOMMAX(MIN_SHRINK_LEN, active_min_gf_interval);
i = (rc->frames_since_key == 0);
max_intervals = cpi->ppi->lap_enabled ? 1 : max_intervals;
int count_cuts = 1;
// If cpi->gf_state.arf_gf_boost_lst is 0, we are starting with a KF or GF.
int cur_start = -1 + !cpi->ppi->gf_state.arf_gf_boost_lst, cur_last;
int cut_pos[MAX_NUM_GF_INTERVALS + 1] = { -1 };
int cut_here;
GF_GROUP_STATS gf_stats;
init_gf_stats(&gf_stats);
while (count_cuts < max_intervals + 1) {
// reaches next key frame, break here
if (i >= rc->frames_to_key) {
cut_here = 2;
}
else if (i - cur_start >= rc->static_scene_max_gf_interval) {
// reached maximum len, but nothing special yet (almost static)
// let's look at the next interval
cut_here = 1;
}
else if (EOF == input_stats(twopass, &cpi->twopass_frame, &next_frame)) {
// reaches last frame, break
cut_here = 2;
}
else {
// Test for the case where there is a brief flash but the prediction
// quality back to an earlier frame is then restored.
flash_detected = detect_flash(twopass, &cpi->twopass_frame, 0);
// TODO(bohanli): remove redundant accumulations here, or unify
// this and the ones in define_gf_group
accumulate_next_frame_stats(&next_frame, flash_detected,
rc->frames_since_key, i, &gf_stats, f_w, f_h);
cut_here = detect_gf_cut(cpi, i, cur_start, flash_detected,
active_max_gf_interval, active_min_gf_interval,
&gf_stats);
}
if (cut_here) {
cur_last = i - 1;
// the current last frame in the gf group
int ori_last = cur_last;
// The region frame idx does not start from the same frame as cur_start
// and cur_last. Need to offset them.
int offset = rc->frames_since_key - p_rc->regions_offset;
REGIONS *regions = p_rc->regions;
int num_regions = p_rc->num_regions;
int scenecut_idx = -1;
// only try shrinking if interval smaller than active_max_gf_interval
if (cur_last - cur_start <= active_max_gf_interval &&
cur_last > cur_start) {
// find the region indices of where the first and last frame belong.
int k_start =
find_regions_index(regions, num_regions, cur_start + offset);
int k_last =
find_regions_index(regions, num_regions, cur_last + offset);
if (cur_start + offset == 0) k_start = 0;
// See if we have a scenecut in between
for (
int r = k_start + 1; r <= k_last; r++) {
if (regions[r].type == SCENECUT_REGION &&
regions[r].last - offset - cur_start > active_min_gf_interval) {
scenecut_idx = r;
break;
}
}
// if the found scenecut is very close to the end, ignore it.
if (regions[num_regions - 1].last - regions[scenecut_idx].last < 4) {
scenecut_idx = -1;
}
if (scenecut_idx != -1) {
// If we have a scenecut, then stop at it.
// TODO(bohanli): add logic here to stop before the scenecut and for
// the next gop start from the scenecut with GF
int is_minor_sc =
(regions[scenecut_idx].avg_cor_coeff *
(1 - stats[regions[scenecut_idx].start - offset].noise_var /
regions[scenecut_idx].avg_intra_err) >
0.6);
cur_last = regions[scenecut_idx].last - offset - !is_minor_sc;
}
else {
int is_last_analysed = (k_last == num_regions - 1) &&
(cur_last + offset == regions[k_last].last);
int not_enough_regions =
k_last - k_start <=
1 + (regions[k_start].type == SCENECUT_REGION);
// if we are very close to the end, then do not shrink since it may
// introduce intervals that are too short
if (!(is_last_analysed && not_enough_regions)) {
const double arf_length_factor = 0.1;
double best_score = 0;
int best_j = -1;
const int first_frame = regions[0].start - offset;
const int last_frame = regions[num_regions - 1].last - offset;
// score of how much the arf helps the whole GOP
double base_score = 0.0;
// Accumulate base_score in
for (
int j = cur_start + 1; j < cur_start + min_shrink_int; j++) {
if (stats + j >= twopass->stats_buf_ctx->stats_in_end)
break;
base_score = (base_score + 1.0) * stats[j].cor_coeff;
}
int met_blending = 0;
// Whether we have met blending areas before
int last_blending = 0;
// Whether the previous frame if blending
for (
int j = cur_start + min_shrink_int; j <= cur_last; j++) {
if (stats + j >= twopass->stats_buf_ctx->stats_in_end)
break;
base_score = (base_score + 1.0) * stats[j].cor_coeff;
int this_reg =
find_regions_index(regions, num_regions, j + offset);
if (this_reg < 0)
continue;
// A GOP should include at most 1 blending region.
if (regions[this_reg].type == BLENDING_REGION) {
last_blending = 1;
if (met_blending) {
break;
}
else {
base_score = 0;
continue;
}
}
else {
if (last_blending) met_blending = 1;
last_blending = 0;
}
// Add the factor of how good the neighborhood is for this
// candidate arf.
double this_score = arf_length_factor * base_score;
double temp_accu_coeff = 1.0;
// following frames
int count_f = 0;
for (
int n = j + 1; n <= j + 3 && n <= last_frame; n++) {
if (stats + n >= twopass->stats_buf_ctx->stats_in_end)
break;
temp_accu_coeff *= stats[n].cor_coeff;
this_score +=
temp_accu_coeff *
sqrt(AOMMAX(0.5,
1 - stats[n].noise_var /
AOMMAX(stats[n].intra_error, 0.001)));
count_f++;
}
// preceding frames
temp_accu_coeff = 1.0;
for (
int n = j; n > j - 3 * 2 + count_f && n > first_frame; n--) {
if (stats + n < twopass->stats_buf_ctx->stats_in_start)
break;
temp_accu_coeff *= stats[n].cor_coeff;
this_score +=
temp_accu_coeff *
sqrt(AOMMAX(0.5,
1 - stats[n].noise_var /
AOMMAX(stats[n].intra_error, 0.001)));
}
if (this_score > best_score) {
best_score = this_score;
best_j = j;
}
}
// For blending areas, move one more frame in case we missed the
// first blending frame.
int best_reg =
find_regions_index(regions, num_regions, best_j + offset);
if (best_reg < num_regions - 1 && best_reg > 0) {
if (regions[best_reg - 1].type == BLENDING_REGION &&
regions[best_reg + 1].type == BLENDING_REGION) {
if (best_j + offset == regions[best_reg].start &&
best_j + offset < regions[best_reg].last) {
best_j += 1;
}
else if (best_j + offset == regions[best_reg].last &&
best_j + offset > regions[best_reg].start) {
best_j -= 1;
}
}
}
if (cur_last - best_j < 2) best_j = cur_last;
if (best_j > 0 && best_score > 0.1) cur_last = best_j;
// if cannot find anything, just cut at the original place.
}
}
}
cut_pos[count_cuts] = cur_last;
count_cuts++;
// reset pointers to the shrunken location
cpi->twopass_frame.stats_in = start_pos + cur_last;
cur_start = cur_last;
int cur_region_idx =
find_regions_index(regions, num_regions, cur_start + 1 + offset);
if (cur_region_idx >= 0)
if (regions[cur_region_idx].type == SCENECUT_REGION) cur_start++;
i = cur_last;
if (cut_here > 1 && cur_last == ori_last)
break;
// reset accumulators
init_gf_stats(&gf_stats);
}
++i;
}
// save intervals
rc->intervals_till_gf_calculate_due = count_cuts - 1;
for (
int n = 1; n < count_cuts; n++) {
p_rc->gf_intervals[n - 1] = cut_pos[n] - cut_pos[n - 1];
}
p_rc->cur_gf_index = 0;
cpi->twopass_frame.stats_in = start_pos;
}
static void correct_frames_to_key(AV1_COMP *cpi) {
int lookahead_size =
(
int)av1_lookahead_depth(cpi->ppi->lookahead, cpi->compressor_stage);
if (lookahead_size <
av1_lookahead_pop_sz(cpi->ppi->lookahead, cpi->compressor_stage)) {
assert(
IMPLIES(cpi->oxcf.pass != AOM_RC_ONE_PASS && cpi->ppi->frames_left > 0,
lookahead_size == cpi->ppi->frames_left));
cpi->rc.frames_to_key = AOMMIN(cpi->rc.frames_to_key, lookahead_size);
}
else if (cpi->ppi->frames_left > 0) {
// Correct frames to key based on limit
cpi->rc.frames_to_key =
AOMMIN(cpi->rc.frames_to_key, cpi->ppi->frames_left);
}
}
/*!\brief Define a GF group in one pass mode when no look ahead stats are
* available.
*
* \ingroup gf_group_algo
* This function defines the structure of a GF group, along with various
* parameters regarding bit-allocation and quality setup in the special
* case of one pass encoding where no lookahead stats are avialable.
*
* \param[in] cpi Top-level encoder structure
*
* \remark Nothing is returned. Instead, cpi->ppi->gf_group is changed.
*/
static void define_gf_group_pass0(AV1_COMP *cpi) {
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
GF_GROUP *
const gf_group = &cpi->ppi->gf_group;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
const GFConfig *
const gf_cfg = &oxcf->gf_cfg;
int target;
if (oxcf->q_cfg.aq_mode == CYCLIC_REFRESH_AQ) {
av1_cyclic_refresh_set_golden_update(cpi);
}
else {
p_rc->baseline_gf_interval = p_rc->gf_intervals[p_rc->cur_gf_index];
rc->intervals_till_gf_calculate_due--;
p_rc->cur_gf_index++;
}
// correct frames_to_key when lookahead queue is flushing
correct_frames_to_key(cpi);
if (p_rc->baseline_gf_interval > rc->frames_to_key)
p_rc->baseline_gf_interval = rc->frames_to_key;
p_rc->gfu_boost = DEFAULT_GF_BOOST;
p_rc->constrained_gf_group =
(p_rc->baseline_gf_interval >= rc->frames_to_key) ? 1 : 0;
gf_group->max_layer_depth_allowed = oxcf->gf_cfg.gf_max_pyr_height;
// Rare case when the look-ahead is less than the target GOP length, can't
// generate ARF frame.
if (p_rc->baseline_gf_interval > gf_cfg->lag_in_frames ||
!is_altref_enabled(gf_cfg->lag_in_frames, gf_cfg->enable_auto_arf) ||
p_rc->baseline_gf_interval < rc->min_gf_interval)
gf_group->max_layer_depth_allowed = 0;
// Set up the structure of this Group-Of-Pictures (same as GF_GROUP)
av1_gop_setup_structure(cpi);
// Allocate bits to each of the frames in the GF group.
// TODO(sarahparker) Extend this to work with pyramid structure.
for (
int cur_index = 0; cur_index < gf_group->size; ++cur_index) {
const FRAME_UPDATE_TYPE cur_update_type = gf_group->update_type[cur_index];
if (oxcf->rc_cfg.mode == AOM_CBR) {
if (cur_update_type == KF_UPDATE) {
target = av1_calc_iframe_target_size_one_pass_cbr(cpi);
}
else {
target = av1_calc_pframe_target_size_one_pass_cbr(cpi, cur_update_type);
}
}
else {
if (cur_update_type == KF_UPDATE) {
target = av1_calc_iframe_target_size_one_pass_vbr(cpi);
}
else {
target = av1_calc_pframe_target_size_one_pass_vbr(cpi, cur_update_type);
}
}
gf_group->bit_allocation[cur_index] = target;
}
}
static inline void set_baseline_gf_interval(PRIMARY_RATE_CONTROL *p_rc,
int arf_position) {
p_rc->baseline_gf_interval = arf_position;
}
// initialize GF_GROUP_STATS
static void init_gf_stats(GF_GROUP_STATS *gf_stats) {
gf_stats->gf_group_err = 0.0;
gf_stats->gf_group_raw_error = 0.0;
gf_stats->gf_group_skip_pct = 0.0;
gf_stats->gf_group_inactive_zone_rows = 0.0;
gf_stats->mv_ratio_accumulator = 0.0;
gf_stats->decay_accumulator = 1.0;
gf_stats->zero_motion_accumulator = 1.0;
gf_stats->loop_decay_rate = 1.0;
gf_stats->last_loop_decay_rate = 1.0;
gf_stats->this_frame_mv_in_out = 0.0;
gf_stats->mv_in_out_accumulator = 0.0;
gf_stats->abs_mv_in_out_accumulator = 0.0;
gf_stats->avg_sr_coded_error = 0.0;
gf_stats->avg_pcnt_second_ref = 0.0;
gf_stats->avg_new_mv_count = 0.0;
gf_stats->avg_wavelet_energy = 0.0;
gf_stats->avg_raw_err_stdev = 0.0;
gf_stats->non_zero_stdev_count = 0;
}
static void accumulate_gop_stats(AV1_COMP *cpi,
int is_intra_only,
int f_w,
int f_h, FIRSTPASS_STATS *next_frame,
const FIRSTPASS_STATS *start_pos,
GF_GROUP_STATS *gf_stats,
int *idx) {
int i, flash_detected;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
RATE_CONTROL *
const rc = &cpi->rc;
FRAME_INFO *frame_info = &cpi->frame_info;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
init_gf_stats(gf_stats);
av1_zero(*next_frame);
// If this is a key frame or the overlay from a previous arf then
// the error score / cost of this frame has already been accounted for.
i = is_intra_only;
// get the determined gf group length from p_rc->gf_intervals
while (i < p_rc->gf_intervals[p_rc->cur_gf_index]) {
// read in the next frame
if (EOF == input_stats(twopass, &cpi->twopass_frame, next_frame))
break;
// Accumulate error score of frames in this gf group.
double mod_frame_err =
calculate_modified_err(frame_info, twopass, oxcf, next_frame);
// accumulate stats for this frame
accumulate_this_frame_stats(next_frame, mod_frame_err, gf_stats);
++i;
}
reset_fpf_position(&cpi->twopass_frame, start_pos);
i = is_intra_only;
input_stats(twopass, &cpi->twopass_frame, next_frame);
while (i < p_rc->gf_intervals[p_rc->cur_gf_index]) {
// read in the next frame
if (EOF == input_stats(twopass, &cpi->twopass_frame, next_frame))
break;
// Test for the case where there is a brief flash but the prediction
// quality back to an earlier frame is then restored.
flash_detected = detect_flash(twopass, &cpi->twopass_frame, 0);
// accumulate stats for next frame
accumulate_next_frame_stats(next_frame, flash_detected,
rc->frames_since_key, i, gf_stats, f_w, f_h);
++i;
}
i = p_rc->gf_intervals[p_rc->cur_gf_index];
average_gf_stats(i, gf_stats);
*idx = i;
}
static void update_gop_length(RATE_CONTROL *rc, PRIMARY_RATE_CONTROL *p_rc,
int idx,
int is_final_pass) {
if (is_final_pass) {
rc->intervals_till_gf_calculate_due--;
p_rc->cur_gf_index++;
}
// Was the group length constrained by the requirement for a new KF?
p_rc->constrained_gf_group = (idx >= rc->frames_to_key) ? 1 : 0;
set_baseline_gf_interval(p_rc, idx);
rc->frames_till_gf_update_due = p_rc->baseline_gf_interval;
}
// #define FIXED_ARF_BITS
#ifdef FIXED_ARF_BITS
#define ARF_BITS_FRACTION 0.75
#endif
/*!\brief Distributes bits to frames in a group
*
*\ingroup rate_control
*
* This function decides on the allocation of bits between the different
* frames and types of frame in a GF/ARF group.
*
* \param[in] cpi Top - level encoder instance structure
* \param[in] rc Rate control data
* \param[in] gf_group GF/ARF group data structure
* \param[in] is_key_frame Indicates if the first frame in the group is
* also a key frame.
* \param[in] use_arf Are ARF frames enabled or is this a GF only
* uni-directional group.
* \param[in] gf_group_bits Bits available to be allocated.
*
* \remark No return but updates the rate control and group data structures
* to reflect the allocation of bits.
*/
static void av1_gop_bit_allocation(
const AV1_COMP *cpi, RATE_CONTROL *
const rc,
GF_GROUP *gf_group,
int is_key_frame,
int use_arf, int64_t gf_group_bits) {
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
// Calculate the extra bits to be used for boosted frame(s)
#ifdef FIXED_ARF_BITS
int gf_arf_bits = (
int)(ARF_BITS_FRACTION * gf_group_bits);
#else
int gf_arf_bits = calculate_boost_bits(
p_rc->baseline_gf_interval - (rc->frames_since_key == 0), p_rc->gfu_boost,
gf_group_bits);
#endif
gf_arf_bits = adjust_boost_bits_for_target_level(cpi, rc, gf_arf_bits,
gf_group_bits, 1);
// Allocate bits to each of the frames in the GF group.
allocate_gf_group_bits(gf_group, p_rc, rc, gf_group_bits, gf_arf_bits,
is_key_frame, use_arf);
}
#undef ARF_BITS_FRACTION
#define MAX_GF_BOOST 5400
#define REDUCE_GF_LENGTH_THRESH 4
#define REDUCE_GF_LENGTH_TO_KEY_THRESH 9
#define REDUCE_GF_LENGTH_BY 1
static void set_gop_bits_boost(AV1_COMP *cpi,
int i,
int is_intra_only,
int is_final_pass,
int use_alt_ref,
int alt_offset,
const FIRSTPASS_STATS *start_pos,
GF_GROUP_STATS *gf_stats) {
// Should we use the alternate reference frame.
AV1_COMMON *
const cm = &cpi->common;
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
GF_GROUP *gf_group = &cpi->ppi->gf_group;
FRAME_INFO *frame_info = &cpi->frame_info;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
const RateControlCfg *
const rc_cfg = &oxcf->rc_cfg;
int ext_len = i - is_intra_only;
if (use_alt_ref) {
const int forward_frames = (rc->frames_to_key - i >= ext_len)
? ext_len
: AOMMAX(0, rc->frames_to_key - i);
// Calculate the boost for alt ref.
p_rc->gfu_boost = av1_calc_arf_boost(
twopass, &cpi->twopass_frame, p_rc, frame_info, alt_offset,
forward_frames, ext_len, &p_rc->num_stats_used_for_gfu_boost,
&p_rc->num_stats_required_for_gfu_boost, cpi->ppi->lap_enabled);
}
else {
reset_fpf_position(&cpi->twopass_frame, start_pos);
p_rc->gfu_boost = AOMMIN(
MAX_GF_BOOST,
av1_calc_arf_boost(
twopass, &cpi->twopass_frame, p_rc, frame_info, alt_offset, ext_len,
0, &p_rc->num_stats_used_for_gfu_boost,
&p_rc->num_stats_required_for_gfu_boost, cpi->ppi->lap_enabled));
}
#define LAST_ALR_BOOST_FACTOR 0.2f
p_rc->arf_boost_factor = 1.0;
if (use_alt_ref && !is_lossless_requested(rc_cfg)) {
// Reduce the boost of altref in the last gf group
if (rc->frames_to_key - ext_len == REDUCE_GF_LENGTH_BY ||
rc->frames_to_key - ext_len == 0) {
p_rc->arf_boost_factor = LAST_ALR_BOOST_FACTOR;
}
}
// Reset the file position.
reset_fpf_position(&cpi->twopass_frame, start_pos);
if (cpi->ppi->lap_enabled) {
// Since we don't have enough stats to know the actual error of the
// gf group, we assume error of each frame to be equal to 1 and set
// the error of the group as baseline_gf_interval.
gf_stats->gf_group_err = p_rc->baseline_gf_interval;
}
// Calculate the bits to be allocated to the gf/arf group as a whole
p_rc->gf_group_bits =
calculate_total_gf_group_bits(cpi, gf_stats->gf_group_err);
#if GROUP_ADAPTIVE_MAXQ
// Calculate an estimate of the maxq needed for the group.
// We are more aggressive about correcting for sections
// where there could be significant overshoot than for easier
// sections where we do not wish to risk creating an overshoot
// of the allocated bit budget.
if ((rc_cfg->mode != AOM_Q) && (p_rc->baseline_gf_interval > 1) &&
is_final_pass) {
const int vbr_group_bits_per_frame =
(
int)(p_rc->gf_group_bits / p_rc->baseline_gf_interval);
const double group_av_err =
gf_stats->gf_group_raw_error / p_rc->baseline_gf_interval;
const double group_av_skip_pct =
gf_stats->gf_group_skip_pct / p_rc->baseline_gf_interval;
const double group_av_inactive_zone =
((gf_stats->gf_group_inactive_zone_rows * 2) /
(p_rc->baseline_gf_interval * (
double)cm->mi_params.mb_rows));
int tmp_q;
tmp_q = get_twopass_worst_quality(
cpi, group_av_err, (group_av_skip_pct + group_av_inactive_zone),
vbr_group_bits_per_frame);
rc->active_worst_quality = AOMMAX(tmp_q, rc->active_worst_quality >> 1);
}
#endif
// Adjust KF group bits and error remaining.
if (is_final_pass) twopass->kf_group_error_left -= gf_stats->gf_group_err;
// Reset the file position.
reset_fpf_position(&cpi->twopass_frame, start_pos);
// Calculate a section intra ratio used in setting max loop filter.
if (rc->frames_since_key != 0) {
twopass->section_intra_rating = calculate_section_intra_ratio(
start_pos, twopass->stats_buf_ctx->stats_in_end,
p_rc->baseline_gf_interval);
}
av1_gop_bit_allocation(cpi, rc, gf_group, rc->frames_since_key == 0,
use_alt_ref, p_rc->gf_group_bits);
// TODO(jingning): Generalize this condition.
if (is_final_pass) {
cpi->ppi->gf_state.arf_gf_boost_lst = use_alt_ref;
// Reset rolling actual and target bits counters for ARF groups.
twopass->rolling_arf_group_target_bits = 1;
twopass->rolling_arf_group_actual_bits = 1;
}
#if CONFIG_BITRATE_ACCURACY
if (is_final_pass) {
av1_vbr_rc_set_gop_bit_budget(&cpi->vbr_rc_info,
p_rc->baseline_gf_interval);
}
#endif
}
/*!\brief Define a GF group.
*
* \ingroup gf_group_algo
* This function defines the structure of a GF group, along with various
* parameters regarding bit-allocation and quality setup.
*
* \param[in] cpi Top-level encoder structure
* \param[in] frame_params Structure with frame parameters
* \param[in] is_final_pass Whether this is the final pass for the
* GF group, or a trial (non-zero)
*
* \remark Nothing is returned. Instead, cpi->ppi->gf_group is changed.
*/
static void define_gf_group(AV1_COMP *cpi, EncodeFrameParams *frame_params,
int is_final_pass) {
AV1_COMMON *
const cm = &cpi->common;
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FIRSTPASS_STATS next_frame;
const FIRSTPASS_STATS *
const start_pos = cpi->twopass_frame.stats_in;
GF_GROUP *gf_group = &cpi->ppi->gf_group;
const GFConfig *
const gf_cfg = &oxcf->gf_cfg;
const RateControlCfg *
const rc_cfg = &oxcf->rc_cfg;
const int f_w = cm->width;
const int f_h = cm->height;
int i;
const int is_intra_only = rc->frames_since_key == 0;
cpi->ppi->internal_altref_allowed = (gf_cfg->gf_max_pyr_height > 1);
// Reset the GF group data structures unless this is a key
// frame in which case it will already have been done.
if (!is_intra_only) {
av1_zero(cpi->ppi->gf_group);
cpi->gf_frame_index = 0;
}
if (has_no_stats_stage(cpi)) {
define_gf_group_pass0(cpi);
return;
}
#if CONFIG_THREE_PASS
if (cpi->third_pass_ctx && oxcf->pass == AOM_RC_THIRD_PASS) {
int ret = define_gf_group_pass3(cpi, frame_params, is_final_pass);
if (ret == 0)
return;
av1_free_thirdpass_ctx(cpi->third_pass_ctx);
cpi->third_pass_ctx = NULL;
}
#endif // CONFIG_THREE_PASS
// correct frames_to_key when lookahead queue is emptying
if (cpi->ppi->lap_enabled) {
correct_frames_to_key(cpi);
}
GF_GROUP_STATS gf_stats;
accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame, start_pos,
&gf_stats, &i);
const int can_disable_arf = !gf_cfg->gf_min_pyr_height;
// If this is a key frame or the overlay from a previous arf then
// the error score / cost of this frame has already been accounted for.
const int active_min_gf_interval = rc->min_gf_interval;
// Disable internal ARFs for "still" gf groups.
// zero_motion_accumulator: minimum percentage of (0,0) motion;
// avg_sr_coded_error: average of the SSE per pixel of each frame;
// avg_raw_err_stdev: average of the standard deviation of (0,0)
// motion error per block of each frame.
const int can_disable_internal_arfs = gf_cfg->gf_min_pyr_height <= 1;
if (can_disable_internal_arfs &&
gf_stats.zero_motion_accumulator > MIN_ZERO_MOTION &&
gf_stats.avg_sr_coded_error < MAX_SR_CODED_ERROR &&
gf_stats.avg_raw_err_stdev < MAX_RAW_ERR_VAR) {
cpi->ppi->internal_altref_allowed = 0;
}
int use_alt_ref;
if (can_disable_arf) {
use_alt_ref =
!is_almost_static(gf_stats.zero_motion_accumulator,
twopass->kf_zeromotion_pct, cpi->ppi->lap_enabled) &&
p_rc->use_arf_in_this_kf_group && (i < gf_cfg->lag_in_frames) &&
(i >= MIN_GF_INTERVAL);
}
else {
use_alt_ref = p_rc->use_arf_in_this_kf_group &&
(i < gf_cfg->lag_in_frames) && (i > 2);
}
if (use_alt_ref) {
gf_group->max_layer_depth_allowed = gf_cfg->gf_max_pyr_height;
}
else {
gf_group->max_layer_depth_allowed = 0;
}
int alt_offset = 0;
// The length reduction strategy is tweaked for certain cases, and doesn't
// work well for certain other cases.
const int allow_gf_length_reduction =
((rc_cfg->mode == AOM_Q && rc_cfg->cq_level <= 128) ||
!cpi->ppi->internal_altref_allowed) &&
!is_lossless_requested(rc_cfg);
if (allow_gf_length_reduction && use_alt_ref) {
// adjust length of this gf group if one of the following condition met
// 1: only one overlay frame left and this gf is too long
// 2: next gf group is too short to have arf compared to the current gf
// maximum length of next gf group
const int next_gf_len = rc->frames_to_key - i;
const int single_overlay_left =
next_gf_len == 0 && i > REDUCE_GF_LENGTH_THRESH;
// the next gf is probably going to have a ARF but it will be shorter than
// this gf
const int unbalanced_gf =
i > REDUCE_GF_LENGTH_TO_KEY_THRESH &&
next_gf_len + 1 < REDUCE_GF_LENGTH_TO_KEY_THRESH &&
next_gf_len + 1 >= rc->min_gf_interval;
if (single_overlay_left || unbalanced_gf) {
const int roll_back = REDUCE_GF_LENGTH_BY;
// Reduce length only if active_min_gf_interval will be respected later.
if (i - roll_back >= active_min_gf_interval + 1) {
alt_offset = -roll_back;
i -= roll_back;
if (is_final_pass) rc->intervals_till_gf_calculate_due = 0;
p_rc->gf_intervals[p_rc->cur_gf_index] -= roll_back;
reset_fpf_position(&cpi->twopass_frame, start_pos);
accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame,
start_pos, &gf_stats, &i);
}
}
}
update_gop_length(rc, p_rc, i, is_final_pass);
// Set up the structure of this Group-Of-Pictures (same as GF_GROUP)
av1_gop_setup_structure(cpi);
set_gop_bits_boost(cpi, i, is_intra_only, is_final_pass, use_alt_ref,
alt_offset, start_pos, &gf_stats);
frame_params->frame_type =
rc->frames_since_key == 0 ? KEY_FRAME : INTER_FRAME;
frame_params->show_frame =
!(gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE ||
gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE);
}
#if CONFIG_THREE_PASS
/*!\brief Define a GF group for the third apss.
*
* \ingroup gf_group_algo
* This function defines the structure of a GF group for the third pass, along
* with various parameters regarding bit-allocation and quality setup based on
* the two-pass bitstream.
* Much of the function still uses the strategies used for the second pass and
* relies on first pass statistics. It is expected that over time these portions
* would be replaced with strategies specific to the third pass.
*
* \param[in] cpi Top-level encoder structure
* \param[in] frame_params Structure with frame parameters
* \param[in] is_final_pass Whether this is the final pass for the
* GF group, or a trial (non-zero)
*
* \return 0: Success;
* -1: There are conflicts between the bitstream and current config
* The values in cpi->ppi->gf_group are also changed.
*/
static int define_gf_group_pass3(AV1_COMP *cpi, EncodeFrameParams *frame_params,
int is_final_pass) {
if (!cpi->third_pass_ctx)
return -1;
AV1_COMMON *
const cm = &cpi->common;
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
FIRSTPASS_STATS next_frame;
const FIRSTPASS_STATS *
const start_pos = cpi->twopass_frame.stats_in;
GF_GROUP *gf_group = &cpi->ppi->gf_group;
const GFConfig *
const gf_cfg = &oxcf->gf_cfg;
const int f_w = cm->width;
const int f_h = cm->height;
int i;
const int is_intra_only = rc->frames_since_key == 0;
cpi->ppi->internal_altref_allowed = (gf_cfg->gf_max_pyr_height > 1);
// Reset the GF group data structures unless this is a key
// frame in which case it will already have been done.
if (!is_intra_only) {
av1_zero(cpi->ppi->gf_group);
cpi->gf_frame_index = 0;
}
GF_GROUP_STATS gf_stats;
accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame, start_pos,
&gf_stats, &i);
const int can_disable_arf = !gf_cfg->gf_min_pyr_height;
// TODO(any): set cpi->ppi->internal_altref_allowed accordingly;
int use_alt_ref = av1_check_use_arf(cpi->third_pass_ctx);
if (use_alt_ref == 0 && !can_disable_arf)
return -1;
if (use_alt_ref) {
gf_group->max_layer_depth_allowed = gf_cfg->gf_max_pyr_height;
}
else {
gf_group->max_layer_depth_allowed = 0;
}
update_gop_length(rc, p_rc, i, is_final_pass);
// Set up the structure of this Group-Of-Pictures (same as GF_GROUP)
av1_gop_setup_structure(cpi);
set_gop_bits_boost(cpi, i, is_intra_only, is_final_pass, use_alt_ref, 0,
start_pos, &gf_stats);
frame_params->frame_type = cpi->third_pass_ctx->frame_info[0].frame_type;
frame_params->show_frame = cpi->third_pass_ctx->frame_info[0].is_show_frame;
return 0;
}
#endif // CONFIG_THREE_PASS
// Minimum % intra coding observed in first pass (1.0 = 100%)
#define MIN_INTRA_LEVEL 0.25
// Minimum ratio between the % of intra coding and inter coding in the first
// pass after discounting neutral blocks (discounting neutral blocks in this
// way helps catch scene cuts in clips with very flat areas or letter box
// format clips with image padding.
#define INTRA_VS_INTER_THRESH 2.0
// Hard threshold where the first pass chooses intra for almost all blocks.
// In such a case even if the frame is not a scene cut coding a key frame
// may be a good option.
#define VERY_LOW_INTER_THRESH 0.05
// Maximum threshold for the relative ratio of intra error score vs best
// inter error score.
#define KF_II_ERR_THRESHOLD 1.9
// In real scene cuts there is almost always a sharp change in the intra
// or inter error score.
#define ERR_CHANGE_THRESHOLD 0.4
// For real scene cuts we expect an improvment in the intra inter error
// ratio in the next frame.
#define II_IMPROVEMENT_THRESHOLD 3.5
#define KF_II_MAX 128.0
// Intra / Inter threshold very low
#define VERY_LOW_II 1.5
// Clean slide transitions we expect a sharp single frame spike in error.
#define ERROR_SPIKE 5.0
// Slide show transition detection.
// Tests for case where there is very low error either side of the current frame
// but much higher just for this frame. This can help detect key frames in
// slide shows even where the slides are pictures of different sizes.
// Also requires that intra and inter errors are very similar to help eliminate
// harmful false positives.
// It will not help if the transition is a fade or other multi-frame effect.
static int slide_transition(
const FIRSTPASS_STATS *this_frame,
const FIRSTPASS_STATS *last_frame,
const FIRSTPASS_STATS *next_frame) {
return (this_frame->intra_error < (this_frame->coded_error * VERY_LOW_II)) &&
(this_frame->coded_error > (last_frame->coded_error * ERROR_SPIKE)) &&
(this_frame->coded_error > (next_frame->coded_error * ERROR_SPIKE));
}
// Threshold for use of the lagging second reference frame. High second ref
// usage may point to a transient event like a flash or occlusion rather than
// a real scene cut.
// We adapt the threshold based on number of frames in this key-frame group so
// far.
static double get_second_ref_usage_thresh(
int frame_count_so_far) {
const int adapt_upto = 32;
const double min_second_ref_usage_thresh = 0.085;
const double second_ref_usage_thresh_max_delta = 0.035;
if (frame_count_so_far >= adapt_upto) {
return min_second_ref_usage_thresh + second_ref_usage_thresh_max_delta;
}
return min_second_ref_usage_thresh +
((
double)frame_count_so_far / (adapt_upto - 1)) *
second_ref_usage_thresh_max_delta;
}
static int test_candidate_kf(
const FIRSTPASS_INFO *firstpass_info,
int this_stats_index,
int frame_count_so_far,
enum aom_rc_mode rc_mode,
int scenecut_mode,
int num_mbs) {
const FIRSTPASS_STATS *last_stats =
av1_firstpass_info_peek(firstpass_info, this_stats_index - 1);
const FIRSTPASS_STATS *this_stats =
av1_firstpass_info_peek(firstpass_info, this_stats_index);
const FIRSTPASS_STATS *next_stats =
av1_firstpass_info_peek(firstpass_info, this_stats_index + 1);
if (last_stats == NULL || this_stats == NULL || next_stats == NULL) {
return 0;
}
int is_viable_kf = 0;
double pcnt_intra = 1.0 - this_stats->pcnt_inter;
double modified_pcnt_inter =
this_stats->pcnt_inter - this_stats->pcnt_neutral;
const double second_ref_usage_thresh =
get_second_ref_usage_thresh(frame_count_so_far);
int frames_to_test_after_candidate_key = SCENE_CUT_KEY_TEST_INTERVAL;
int count_for_tolerable_prediction = 3;
// We do "-1" because the candidate key is not counted.
int stats_after_this_stats =
av1_firstpass_info_future_count(firstpass_info, this_stats_index) - 1;
if (scenecut_mode == ENABLE_SCENECUT_MODE_1) {
if (stats_after_this_stats < 3) {
return 0;
}
else {
frames_to_test_after_candidate_key = 3;
count_for_tolerable_prediction = 1;
}
}
// Make sure we have enough stats after the candidate key.
frames_to_test_after_candidate_key =
AOMMIN(frames_to_test_after_candidate_key, stats_after_this_stats);
// Does the frame satisfy the primary criteria of a key frame?
// See above for an explanation of the test criteria.
// If so, then examine how well it predicts subsequent frames.
if (IMPLIES(rc_mode == AOM_Q, frame_count_so_far >= 3) &&
(this_stats->pcnt_second_ref < second_ref_usage_thresh) &&
(next_stats->pcnt_second_ref < second_ref_usage_thresh) &&
((this_stats->pcnt_inter < VERY_LOW_INTER_THRESH) ||
slide_transition(this_stats, last_stats, next_stats) ||
((pcnt_intra > MIN_INTRA_LEVEL) &&
(pcnt_intra > (INTRA_VS_INTER_THRESH * modified_pcnt_inter)) &&
((this_stats->intra_error /
DOUBLE_DIVIDE_CHECK(this_stats->coded_error)) <
KF_II_ERR_THRESHOLD) &&
((fabs(last_stats->coded_error - this_stats->coded_error) /
DOUBLE_DIVIDE_CHECK(this_stats->coded_error) >
ERR_CHANGE_THRESHOLD) ||
(fabs(last_stats->intra_error - this_stats->intra_error) /
DOUBLE_DIVIDE_CHECK(this_stats->intra_error) >
ERR_CHANGE_THRESHOLD) ||
((next_stats->intra_error /
DOUBLE_DIVIDE_CHECK(next_stats->coded_error)) >
II_IMPROVEMENT_THRESHOLD))))) {
int i;
double boost_score = 0.0;
double old_boost_score = 0.0;
double decay_accumulator = 1.0;
// Examine how well the key frame predicts subsequent frames.
for (i = 1; i <= frames_to_test_after_candidate_key; ++i) {
// Get the next frame details
const FIRSTPASS_STATS *local_next_frame =
av1_firstpass_info_peek(firstpass_info, this_stats_index + i);
double next_iiratio =
(BOOST_FACTOR * local_next_frame->intra_error /
DOUBLE_DIVIDE_CHECK(local_next_frame->coded_error));
if (next_iiratio > KF_II_MAX) next_iiratio = KF_II_MAX;
// Cumulative effect of decay in prediction quality.
if (local_next_frame->pcnt_inter > 0.85)
decay_accumulator *= local_next_frame->pcnt_inter;
else
decay_accumulator *= (0.85 + local_next_frame->pcnt_inter) / 2.0;
// Keep a running total.
boost_score += (decay_accumulator * next_iiratio);
// Test various breakout clauses.
// TODO(any): Test of intra error should be normalized to an MB.
if ((local_next_frame->pcnt_inter < 0.05) || (next_iiratio < 1.5) ||
(((local_next_frame->pcnt_inter - local_next_frame->pcnt_neutral) <
0.20) &&
(next_iiratio < 3.0)) ||
((boost_score - old_boost_score) < 3.0) ||
(local_next_frame->intra_error < (200.0 / (
double)num_mbs))) {
break;
}
old_boost_score = boost_score;
}
// If there is tolerable prediction for at least the next 3 frames then
// break out else discard this potential key frame and move on
if (boost_score > 30.0 && (i > count_for_tolerable_prediction)) {
is_viable_kf = 1;
}
else {
is_viable_kf = 0;
}
}
return is_viable_kf;
}
#define FRAMES_TO_CHECK_DECAY 8
#define KF_MIN_FRAME_BOOST 80.0
#define KF_MAX_FRAME_BOOST 128.0
#define MIN_KF_BOOST 600
// Minimum boost for non-static KF interval
#define MAX_KF_BOOST 3200
#define MIN_STATIC_KF_BOOST 5400
// Minimum boost for static KF interval
static int detect_app_forced_key(AV1_COMP *cpi) {
int num_frames_to_app_forced_key = is_forced_keyframe_pending(
cpi->ppi->lookahead, cpi->ppi->lookahead->max_sz, cpi->compressor_stage);
return num_frames_to_app_forced_key;
}
static int get_projected_kf_boost(AV1_COMP *cpi) {
/*
* If num_stats_used_for_kf_boost >= frames_to_key, then
* all stats needed for prior boost calculation are available.
* Hence projecting the prior boost is not needed in this cases.
*/
if (cpi->ppi->p_rc.num_stats_used_for_kf_boost >= cpi->rc.frames_to_key)
return cpi->ppi->p_rc.kf_boost;
// Get the current tpl factor (number of frames = frames_to_key).
double tpl_factor = av1_get_kf_boost_projection_factor(cpi->rc.frames_to_key);
// Get the tpl factor when number of frames = num_stats_used_for_kf_boost.
double tpl_factor_num_stats = av1_get_kf_boost_projection_factor(
cpi->ppi->p_rc.num_stats_used_for_kf_boost);
int projected_kf_boost =
(
int)rint((tpl_factor * cpi->ppi->p_rc.kf_boost) / tpl_factor_num_stats);
return projected_kf_boost;
}
/*!\brief Determine the location of the next key frame
*
* \ingroup gf_group_algo
* This function decides the placement of the next key frame when a
* scenecut is detected or the maximum key frame distance is reached.
*
* \param[in] cpi Top-level encoder structure
* \param[in] firstpass_info struct for firstpass info
* \param[in] num_frames_to_detect_scenecut Maximum lookahead frames.
* \param[in] search_start_idx the start index for searching key frame.
* Set it to one if we already know the
* current frame is key frame. Otherwise,
* set it to zero.
*
* \return Number of frames to the next key including the current frame.
*/
static int define_kf_interval(AV1_COMP *cpi,
const FIRSTPASS_INFO *firstpass_info,
int num_frames_to_detect_scenecut,
int search_start_idx) {
const TWO_PASS *
const twopass = &cpi->ppi->twopass;
const RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
const KeyFrameCfg *
const kf_cfg = &oxcf->kf_cfg;
double recent_loop_decay[FRAMES_TO_CHECK_DECAY];
double decay_accumulator = 1.0;
int i = 0, j;
int frames_to_key = search_start_idx;
int frames_since_key = rc->frames_since_key + 1;
int scenecut_detected = 0;
int num_frames_to_next_key = detect_app_forced_key(cpi);
if (num_frames_to_detect_scenecut == 0) {
if (num_frames_to_next_key != -1)
return num_frames_to_next_key;
else
return rc->frames_to_key;
}
if (num_frames_to_next_key != -1)
num_frames_to_detect_scenecut =
AOMMIN(num_frames_to_detect_scenecut, num_frames_to_next_key);
// Initialize the decay rates for the recent frames to check
for (j = 0; j < FRAMES_TO_CHECK_DECAY; ++j) recent_loop_decay[j] = 1.0;
i = 0;
const int num_mbs = (oxcf->resize_cfg.resize_mode != RESIZE_NONE)
? cpi->initial_mbs
: cpi->common.mi_params.MBs;
const int future_stats_count =
av1_firstpass_info_future_count(firstpass_info, 0);
while (frames_to_key < future_stats_count &&
frames_to_key < num_frames_to_detect_scenecut) {
// Provided that we are not at the end of the file...
if ((cpi->ppi->p_rc.enable_scenecut_detection > 0) && kf_cfg->auto_key &&
frames_to_key + 1 < future_stats_count) {
double loop_decay_rate;
// Check for a scene cut.
if (frames_since_key >= kf_cfg->key_freq_min) {
scenecut_detected = test_candidate_kf(
&twopass->firstpass_info, frames_to_key, frames_since_key,
oxcf->rc_cfg.mode, cpi->ppi->p_rc.enable_scenecut_detection,
num_mbs);
if (scenecut_detected) {
break;
}
}
// How fast is the prediction quality decaying?
const FIRSTPASS_STATS *next_stats =
av1_firstpass_info_peek(firstpass_info, frames_to_key + 1);
loop_decay_rate = get_prediction_decay_rate(next_stats);
// We want to know something about the recent past... rather than
// as used elsewhere where we are concerned with decay in prediction
// quality since the last GF or KF.
recent_loop_decay[i % FRAMES_TO_CHECK_DECAY] = loop_decay_rate;
decay_accumulator = 1.0;
for (j = 0; j < FRAMES_TO_CHECK_DECAY; ++j)
decay_accumulator *= recent_loop_decay[j];
// Special check for transition or high motion followed by a
// static scene.
if (frames_since_key >= kf_cfg->key_freq_min) {
scenecut_detected = detect_transition_to_still(
firstpass_info, frames_to_key + 1, rc->min_gf_interval, i,
kf_cfg->key_freq_max - i, loop_decay_rate, decay_accumulator);
if (scenecut_detected) {
// In the case of transition followed by a static scene, the key frame
// could be a good predictor for the following frames, therefore we
// do not use an arf.
p_rc->use_arf_in_this_kf_group = 0;
break;
}
}
// Step on to the next frame.
++frames_to_key;
++frames_since_key;
// If we don't have a real key frame within the next two
// key_freq_max intervals then break out of the loop.
if (frames_to_key >= 2 * kf_cfg->key_freq_max) {
break;
}
}
else {
++frames_to_key;
++frames_since_key;
}
++i;
}
if (cpi->ppi->lap_enabled && !scenecut_detected)
frames_to_key = num_frames_to_next_key;
return frames_to_key;
}
static double get_kf_group_avg_error(TWO_PASS *twopass,
TWO_PASS_FRAME *twopass_frame,
const FIRSTPASS_STATS *first_frame,
const FIRSTPASS_STATS *start_position,
int frames_to_key) {
FIRSTPASS_STATS cur_frame = *first_frame;
int num_frames, i;
double kf_group_avg_error = 0.0;
reset_fpf_position(twopass_frame, start_position);
for (i = 0; i < frames_to_key; ++i) {
kf_group_avg_error += cur_frame.coded_error;
if (EOF == input_stats(twopass, twopass_frame, &cur_frame))
break;
}
num_frames = i + 1;
num_frames = AOMMIN(num_frames, frames_to_key);
kf_group_avg_error = kf_group_avg_error / num_frames;
return (kf_group_avg_error);
}
static int64_t get_kf_group_bits(AV1_COMP *cpi,
double kf_group_err,
double kf_group_avg_error) {
RATE_CONTROL *
const rc = &cpi->rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
int64_t kf_group_bits;
if (cpi->ppi->lap_enabled) {
kf_group_bits = (int64_t)rc->frames_to_key * rc->avg_frame_bandwidth;
if (cpi->oxcf.rc_cfg.vbr_corpus_complexity_lap) {
double vbr_corpus_complexity_lap =
cpi->oxcf.rc_cfg.vbr_corpus_complexity_lap / 10.0;
/* Get the average corpus complexity of the frame */
kf_group_bits = (int64_t)(kf_group_bits * (kf_group_avg_error /
vbr_corpus_complexity_lap));
}
}
else {
kf_group_bits = (int64_t)(twopass->bits_left *
(kf_group_err / twopass->modified_error_left));
}
return kf_group_bits;
}
static int calc_avg_stats(AV1_COMP *cpi, FIRSTPASS_STATS *avg_frame_stat) {
RATE_CONTROL *
const rc = &cpi->rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FIRSTPASS_STATS cur_frame;
av1_zero(cur_frame);
int num_frames = 0;
// Accumulate total stat using available number of stats.
for (num_frames = 0; num_frames < (rc->frames_to_key - 1); ++num_frames) {
if (EOF == input_stats(twopass, &cpi->twopass_frame, &cur_frame))
break;
av1_accumulate_stats(avg_frame_stat, &cur_frame);
}
if (num_frames < 2) {
return num_frames;
}
// Average the total stat
avg_frame_stat->weight = avg_frame_stat->weight / num_frames;
avg_frame_stat->intra_error = avg_frame_stat->intra_error / num_frames;
avg_frame_stat->frame_avg_wavelet_energy =
avg_frame_stat->frame_avg_wavelet_energy / num_frames;
avg_frame_stat->coded_error = avg_frame_stat->coded_error / num_frames;
avg_frame_stat->sr_coded_error = avg_frame_stat->sr_coded_error / num_frames;
avg_frame_stat->pcnt_inter = avg_frame_stat->pcnt_inter / num_frames;
avg_frame_stat->pcnt_motion = avg_frame_stat->pcnt_motion / num_frames;
avg_frame_stat->pcnt_second_ref =
avg_frame_stat->pcnt_second_ref / num_frames;
avg_frame_stat->pcnt_neutral = avg_frame_stat->pcnt_neutral / num_frames;
avg_frame_stat->intra_skip_pct = avg_frame_stat->intra_skip_pct / num_frames;
avg_frame_stat->inactive_zone_rows =
avg_frame_stat->inactive_zone_rows / num_frames;
avg_frame_stat->inactive_zone_cols =
avg_frame_stat->inactive_zone_cols / num_frames;
avg_frame_stat->MVr = avg_frame_stat->MVr / num_frames;
avg_frame_stat->mvr_abs = avg_frame_stat->mvr_abs / num_frames;
avg_frame_stat->MVc = avg_frame_stat->MVc / num_frames;
avg_frame_stat->mvc_abs = avg_frame_stat->mvc_abs / num_frames;
avg_frame_stat->MVrv = avg_frame_stat->MVrv / num_frames;
avg_frame_stat->MVcv = avg_frame_stat->MVcv / num_frames;
avg_frame_stat->mv_in_out_count =
avg_frame_stat->mv_in_out_count / num_frames;
avg_frame_stat->new_mv_count = avg_frame_stat->new_mv_count / num_frames;
avg_frame_stat->count = avg_frame_stat->count / num_frames;
avg_frame_stat->duration = avg_frame_stat->duration / num_frames;
return num_frames;
}
static double get_kf_boost_score(AV1_COMP *cpi,
double kf_raw_err,
double *zero_motion_accumulator,
double *sr_accumulator,
int use_avg_stat) {
RATE_CONTROL *
const rc = &cpi->rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FRAME_INFO *
const frame_info = &cpi->frame_info;
FIRSTPASS_STATS frame_stat;
av1_zero(frame_stat);
int i = 0, num_stat_used = 0;
double boost_score = 0.0;
const double kf_max_boost =
cpi->oxcf.rc_cfg.mode == AOM_Q
? AOMMIN(AOMMAX(rc->frames_to_key * 2.0, KF_MIN_FRAME_BOOST),
KF_MAX_FRAME_BOOST)
: KF_MAX_FRAME_BOOST;
// Calculate the average using available number of stats.
if (use_avg_stat) num_stat_used = calc_avg_stats(cpi, &frame_stat);
for (i = num_stat_used; i < (rc->frames_to_key - 1); ++i) {
if (!use_avg_stat &&
EOF == input_stats(twopass, &cpi->twopass_frame, &frame_stat))
break;
// Monitor for static sections.
// For the first frame in kf group, the second ref indicator is invalid.
if (i > 0) {
*zero_motion_accumulator =
AOMMIN(*zero_motion_accumulator, get_zero_motion_factor(&frame_stat));
}
else {
*zero_motion_accumulator = frame_stat.pcnt_inter - frame_stat.pcnt_motion;
}
// Not all frames in the group are necessarily used in calculating boost.
if ((*sr_accumulator < (kf_raw_err * 1.50)) &&
(i <= rc->max_gf_interval * 2)) {
double frame_boost;
double zm_factor;
// Factor 0.75-1.25 based on how much of frame is static.
zm_factor = (0.75 + (*zero_motion_accumulator / 2.0));
if (i < 2) *sr_accumulator = 0.0;
frame_boost =
calc_kf_frame_boost(&cpi->ppi->p_rc, frame_info, &frame_stat,
sr_accumulator, kf_max_boost);
boost_score += frame_boost * zm_factor;
}
}
return boost_score;
}
/*!\brief Interval(in seconds) to clip key-frame distance to in LAP.
*/
#define MAX_KF_BITS_INTERVAL_SINGLE_PASS 5
/*!\brief Determine the next key frame group
*
* \ingroup gf_group_algo
* This function decides the placement of the next key frame, and
* calculates the bit allocation of the KF group and the keyframe itself.
*
* \param[in] cpi Top-level encoder structure
* \param[in] this_frame Pointer to first pass stats
*/
static void find_next_key_frame(AV1_COMP *cpi, FIRSTPASS_STATS *this_frame) {
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
GF_GROUP *
const gf_group = &cpi->ppi->gf_group;
FRAME_INFO *
const frame_info = &cpi->frame_info;
AV1_COMMON *
const cm = &cpi->common;
CurrentFrame *
const current_frame = &cm->current_frame;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
const KeyFrameCfg *
const kf_cfg = &oxcf->kf_cfg;
const FIRSTPASS_STATS first_frame = *this_frame;
FIRSTPASS_STATS next_frame;
const FIRSTPASS_INFO *firstpass_info = &twopass->firstpass_info;
av1_zero(next_frame);
rc->frames_since_key = 0;
// Use arfs if possible.
p_rc->use_arf_in_this_kf_group = is_altref_enabled(
oxcf->gf_cfg.lag_in_frames, oxcf->gf_cfg.enable_auto_arf);
// Reset the GF group data structures.
av1_zero(*gf_group);
cpi->gf_frame_index = 0;
// KF is always a GF so clear frames till next gf counter.
rc->frames_till_gf_update_due = 0;
if (has_no_stats_stage(cpi)) {
int num_frames_to_app_forced_key = detect_app_forced_key(cpi);
p_rc->this_key_frame_forced =
current_frame->frame_number != 0 && rc->frames_to_key == 0;
if (num_frames_to_app_forced_key != -1)
rc->frames_to_key = num_frames_to_app_forced_key;
else
rc->frames_to_key = AOMMAX(1, kf_cfg->key_freq_max);
correct_frames_to_key(cpi);
p_rc->kf_boost = DEFAULT_KF_BOOST;
gf_group->update_type[0] = KF_UPDATE;
return;
}
int i;
const FIRSTPASS_STATS *
const start_position = cpi->twopass_frame.stats_in;
int kf_bits = 0;
double zero_motion_accumulator = 1.0;
double boost_score = 0.0;
double kf_raw_err = 0.0;
double kf_mod_err = 0.0;
double sr_accumulator = 0.0;
double kf_group_avg_error = 0.0;
int frames_to_key, frames_to_key_clipped = INT_MAX;
int64_t kf_group_bits_clipped = INT64_MAX;
// Is this a forced key frame by interval.
p_rc->this_key_frame_forced = p_rc->next_key_frame_forced;
twopass->kf_group_bits = 0;
// Total bits available to kf group
twopass->kf_group_error_left = 0;
// Group modified error score.
kf_raw_err = this_frame->intra_error;
kf_mod_err = calculate_modified_err(frame_info, twopass, oxcf, this_frame);
// We assume the current frame is a key frame and we are looking for the next
// key frame. Therefore search_start_idx = 1
frames_to_key = define_kf_interval(cpi, firstpass_info, kf_cfg->key_freq_max,
/*search_start_idx=*/1);
if (frames_to_key != -1) {
rc->frames_to_key = AOMMIN(kf_cfg->key_freq_max, frames_to_key);
}
else {
rc->frames_to_key = kf_cfg->key_freq_max;
}
if (cpi->ppi->lap_enabled) correct_frames_to_key(cpi);
// If there is a max kf interval set by the user we must obey it.
// We already breakout of the loop above at 2x max.
// This code centers the extra kf if the actual natural interval
// is between 1x and 2x.
if (kf_cfg->auto_key && rc->frames_to_key > kf_cfg->key_freq_max) {
FIRSTPASS_STATS tmp_frame = first_frame;
rc->frames_to_key /= 2;
// Reset to the start of the group.
reset_fpf_position(&cpi->twopass_frame, start_position);
// Rescan to get the correct error data for the forced kf group.
for (i = 0; i < rc->frames_to_key; ++i) {
if (EOF == input_stats(twopass, &cpi->twopass_frame, &tmp_frame))
break;
}
p_rc->next_key_frame_forced = 1;
}
else if ((cpi->twopass_frame.stats_in ==
twopass->stats_buf_ctx->stats_in_end &&
is_stat_consumption_stage_twopass(cpi)) ||
rc->frames_to_key >= kf_cfg->key_freq_max) {
p_rc->next_key_frame_forced = 1;
}
else {
p_rc->next_key_frame_forced = 0;
}
double kf_group_err = 0;
for (i = 0; i < rc->frames_to_key; ++i) {
const FIRSTPASS_STATS *this_stats =
av1_firstpass_info_peek(&twopass->firstpass_info, i);
if (this_stats != NULL) {
// Accumulate kf group error.
kf_group_err += calculate_modified_err_new(
frame_info, &firstpass_info->total_stats, this_stats,
oxcf->rc_cfg.vbrbias, twopass->modified_error_min,
twopass->modified_error_max);
++p_rc->num_stats_used_for_kf_boost;
}
}
// Calculate the number of bits that should be assigned to the kf group.
if ((twopass->bits_left > 0 && twopass->modified_error_left > 0.0) ||
(cpi->ppi->lap_enabled && oxcf->rc_cfg.mode != AOM_Q)) {
// Maximum number of bits for a single normal frame (not key frame).
const int max_bits = frame_max_bits(rc, oxcf);
// Maximum number of bits allocated to the key frame group.
int64_t max_grp_bits;
if (oxcf->rc_cfg.vbr_corpus_complexity_lap) {
kf_group_avg_error =
get_kf_group_avg_error(twopass, &cpi->twopass_frame, &first_frame,
start_position, rc->frames_to_key);
}
// Default allocation based on bits left and relative
// complexity of the section.
twopass->kf_group_bits =
get_kf_group_bits(cpi, kf_group_err, kf_group_avg_error);
// Clip based on maximum per frame rate defined by the user.
max_grp_bits = (int64_t)max_bits * (int64_t)rc->frames_to_key;
if (twopass->kf_group_bits > max_grp_bits)
twopass->kf_group_bits = max_grp_bits;
}
else {
twopass->kf_group_bits = 0;
}
twopass->kf_group_bits = AOMMAX(0, twopass->kf_group_bits);
if (cpi->ppi->lap_enabled) {
// In the case of single pass based on LAP, frames to key may have an
// inaccurate value, and hence should be clipped to an appropriate
// interval.
frames_to_key_clipped =
(
int)(MAX_KF_BITS_INTERVAL_SINGLE_PASS * cpi->framerate);
// This variable calculates the bits allocated to kf_group with a clipped
// frames_to_key.
if (rc->frames_to_key > frames_to_key_clipped) {
kf_group_bits_clipped =
(int64_t)((
double)twopass->kf_group_bits * frames_to_key_clipped /
rc->frames_to_key);
}
}
// Reset the first pass file position.
reset_fpf_position(&cpi->twopass_frame, start_position);
// Scan through the kf group collating various stats used to determine
// how many bits to spend on it.
boost_score = get_kf_boost_score(cpi, kf_raw_err, &zero_motion_accumulator,
&sr_accumulator, 0);
reset_fpf_position(&cpi->twopass_frame, start_position);
// Store the zero motion percentage
twopass->kf_zeromotion_pct = (
int)(zero_motion_accumulator * 100.0);
// Calculate a section intra ratio used in setting max loop filter.
twopass->section_intra_rating = calculate_section_intra_ratio(
start_position, twopass->stats_buf_ctx->stats_in_end, rc->frames_to_key);
p_rc->kf_boost = (
int)boost_score;
if (cpi->ppi->lap_enabled) {
if (oxcf->rc_cfg.mode == AOM_Q) {
p_rc->kf_boost = get_projected_kf_boost(cpi);
}
else {
// TODO(any): Explore using average frame stats for AOM_Q as well.
boost_score = get_kf_boost_score(
cpi, kf_raw_err, &zero_motion_accumulator, &sr_accumulator, 1);
reset_fpf_position(&cpi->twopass_frame, start_position);
p_rc->kf_boost += (
int)boost_score;
}
}
// Special case for static / slide show content but don't apply
// if the kf group is very short.
if ((zero_motion_accumulator > STATIC_KF_GROUP_FLOAT_THRESH) &&
(rc->frames_to_key > 8)) {
p_rc->kf_boost = AOMMAX(p_rc->kf_boost, MIN_STATIC_KF_BOOST);
}
else {
// Apply various clamps for min and max boost
p_rc->kf_boost = AOMMAX(p_rc->kf_boost, (rc->frames_to_key * 3));
p_rc->kf_boost = AOMMAX(p_rc->kf_boost, MIN_KF_BOOST);
#ifdef STRICT_RC
p_rc->kf_boost = AOMMIN(p_rc->kf_boost, MAX_KF_BOOST);
#endif
}
// Work out how many bits to allocate for the key frame itself.
// In case of LAP enabled for VBR, if the frames_to_key value is
// very high, we calculate the bits based on a clipped value of
// frames_to_key.
kf_bits = calculate_boost_bits(
AOMMIN(rc->frames_to_key, frames_to_key_clipped) - 1, p_rc->kf_boost,
AOMMIN(twopass->kf_group_bits, kf_group_bits_clipped));
// printf("kf boost = %d kf_bits = %d kf_zeromotion_pct = %d\n",
// p_rc->kf_boost,
// kf_bits, twopass->kf_zeromotion_pct);
kf_bits = adjust_boost_bits_for_target_level(cpi, rc, kf_bits,
twopass->kf_group_bits, 0);
twopass->kf_group_bits -= kf_bits;
// Save the bits to spend on the key frame.
gf_group->bit_allocation[0] = kf_bits;
gf_group->update_type[0] = KF_UPDATE;
// Note the total error score of the kf group minus the key frame itself.
if (cpi->ppi->lap_enabled)
// As we don't have enough stats to know the actual error of the group,
// we assume the complexity of each frame to be equal to 1, and set the
// error as the number of frames in the group(minus the keyframe).
twopass->kf_group_error_left = (
double)(rc->frames_to_key - 1);
else
twopass->kf_group_error_left = kf_group_err - kf_mod_err;
// Adjust the count of total modified error left.
// The count of bits left is adjusted elsewhere based on real coded frame
// sizes.
twopass->modified_error_left -= kf_group_err;
}
#define ARF_STATS_OUTPUT 0
#if ARF_STATS_OUTPUT
unsigned int arf_count = 0;
#endif
static int get_section_target_bandwidth(AV1_COMP *cpi) {
AV1_COMMON *
const cm = &cpi->common;
CurrentFrame *
const current_frame = &cm->current_frame;
RATE_CONTROL *
const rc = &cpi->rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
int64_t section_target_bandwidth;
const int frames_left = (
int)(twopass->stats_buf_ctx->total_stats->count -
current_frame->frame_number);
if (cpi->ppi->lap_enabled)
section_target_bandwidth = rc->avg_frame_bandwidth;
else {
section_target_bandwidth = twopass->bits_left / frames_left;
section_target_bandwidth = AOMMIN(section_target_bandwidth, INT_MAX);
}
return (
int)section_target_bandwidth;
}
static inline void set_twopass_params_based_on_fp_stats(
AV1_COMP *cpi,
const FIRSTPASS_STATS *this_frame_ptr) {
if (this_frame_ptr == NULL)
return;
TWO_PASS_FRAME *twopass_frame = &cpi->twopass_frame;
// The multiplication by 256 reverses a scaling factor of (>> 8)
// applied when combining MB error values for the frame.
twopass_frame->mb_av_energy = log1p(this_frame_ptr->intra_error);
const FIRSTPASS_STATS *
const total_stats =
cpi->ppi->twopass.stats_buf_ctx->total_stats;
if (is_fp_wavelet_energy_invalid(total_stats) == 0) {
twopass_frame->frame_avg_haar_energy =
log1p(this_frame_ptr->frame_avg_wavelet_energy);
}
// Set the frame content type flag.
if (this_frame_ptr->intra_skip_pct >= FC_ANIMATION_THRESH)
twopass_frame->fr_content_type = FC_GRAPHICS_ANIMATION;
else
twopass_frame->fr_content_type = FC_NORMAL;
}
static void process_first_pass_stats(AV1_COMP *cpi,
FIRSTPASS_STATS *this_frame) {
AV1_COMMON *
const cm = &cpi->common;
CurrentFrame *
const current_frame = &cm->current_frame;
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FIRSTPASS_STATS *total_stats = twopass->stats_buf_ctx->total_stats;
if (cpi->oxcf.rc_cfg.mode != AOM_Q && current_frame->frame_number == 0 &&
cpi->gf_frame_index == 0 && total_stats &&
twopass->stats_buf_ctx->total_left_stats) {
if (cpi->ppi->lap_enabled) {
/*
* Accumulate total_stats using available limited number of stats,
* and assign it to total_left_stats.
*/
*twopass->stats_buf_ctx->total_left_stats = *total_stats;
}
// Special case code for first frame.
const int section_target_bandwidth = get_section_target_bandwidth(cpi);
const double section_length =
twopass->stats_buf_ctx->total_left_stats->count;
const double section_error =
twopass->stats_buf_ctx->total_left_stats->coded_error / section_length;
const double section_intra_skip =
twopass->stats_buf_ctx->total_left_stats->intra_skip_pct /
section_length;
const double section_inactive_zone =
(twopass->stats_buf_ctx->total_left_stats->inactive_zone_rows * 2) /
((
double)cm->mi_params.mb_rows * section_length);
const int tmp_q = get_twopass_worst_quality(
cpi, section_error, section_intra_skip + section_inactive_zone,
section_target_bandwidth);
rc->active_worst_quality = tmp_q;
rc->ni_av_qi = tmp_q;
p_rc->last_q[INTER_FRAME] = tmp_q;
p_rc->avg_q = av1_convert_qindex_to_q(tmp_q, cm->seq_params->bit_depth);
p_rc->avg_frame_qindex[INTER_FRAME] = tmp_q;
p_rc->last_q[KEY_FRAME] = (tmp_q + cpi->oxcf.rc_cfg.best_allowed_q) / 2;
p_rc->avg_frame_qindex[KEY_FRAME] = p_rc->last_q[KEY_FRAME];
}
if (cpi->twopass_frame.stats_in < twopass->stats_buf_ctx->stats_in_end) {
*this_frame = *cpi->twopass_frame.stats_in;
++cpi->twopass_frame.stats_in;
}
set_twopass_params_based_on_fp_stats(cpi, this_frame);
}
static void setup_target_rate(AV1_COMP *cpi) {
RATE_CONTROL *
const rc = &cpi->rc;
GF_GROUP *
const gf_group = &cpi->ppi->gf_group;
int target_rate = gf_group->bit_allocation[cpi->gf_frame_index];
if (has_no_stats_stage(cpi)) {
av1_rc_set_frame_target(cpi, target_rate, cpi->common.width,
cpi->common.height);
}
rc->base_frame_target = target_rate;
}
static void mark_flashes(FIRSTPASS_STATS *first_stats,
FIRSTPASS_STATS *last_stats) {
FIRSTPASS_STATS *this_stats = first_stats, *next_stats;
while (this_stats < last_stats - 1) {
next_stats = this_stats + 1;
if (next_stats->pcnt_second_ref > next_stats->pcnt_inter &&
next_stats->pcnt_second_ref >= 0.5) {
this_stats->is_flash = 1;
}
else {
this_stats->is_flash = 0;
}
this_stats = next_stats;
}
// We always treat the last one as none flash.
if (last_stats - 1 >= first_stats) {
(last_stats - 1)->is_flash = 0;
}
}
// Smooth-out the noise variance so it is more stable
// Returns 0 on success, -1 on memory allocation failure.
// TODO(bohanli): Use a better low-pass filter than averaging
static int smooth_filter_noise(FIRSTPASS_STATS *first_stats,
FIRSTPASS_STATS *last_stats) {
int len = (
int)(last_stats - first_stats);
double *smooth_noise = aom_malloc(len *
sizeof(*smooth_noise));
if (!smooth_noise)
return -1;
for (
int i = 0; i < len; i++) {
double total_noise = 0;
double total_wt = 0;
for (
int j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) {
int idx = AOMMIN(AOMMAX(i + j, 0), len - 1);
if (first_stats[idx].is_flash)
continue;
total_noise += first_stats[idx].noise_var;
total_wt += 1.0;
}
if (total_wt > 0.01) {
total_noise /= total_wt;
}
else {
total_noise = first_stats[i].noise_var;
}
smooth_noise[i] = total_noise;
}
for (
int i = 0; i < len; i++) {
first_stats[i].noise_var = smooth_noise[i];
}
aom_free(smooth_noise);
return 0;
}
// Estimate the noise variance of each frame from the first pass stats
static void estimate_noise(FIRSTPASS_STATS *first_stats,
FIRSTPASS_STATS *last_stats,
struct aom_internal_error_info *error_info) {
FIRSTPASS_STATS *this_stats, *next_stats;
double C1, C2, C3, noise;
for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) {
this_stats->noise_var = 0.0;
// flashes tend to have high correlation of innovations, so ignore them.
if (this_stats->is_flash || (this_stats - 1)->is_flash ||
(this_stats - 2)->is_flash)
continue;
C1 = (this_stats - 1)->intra_error *
(this_stats->intra_error - this_stats->coded_error);
C2 = (this_stats - 2)->intra_error *
((this_stats - 1)->intra_error - (this_stats - 1)->coded_error);
C3 = (this_stats - 2)->intra_error *
(this_stats->intra_error - this_stats->sr_coded_error);
if (C1 <= 0 || C2 <= 0 || C3 <= 0)
continue;
C1 = sqrt(C1);
C2 = sqrt(C2);
C3 = sqrt(C3);
noise = (this_stats - 1)->intra_error - C1 * C2 / C3;
noise = AOMMAX(noise, 0.01);
this_stats->noise_var = noise;
}
// Copy noise from the neighbor if the noise value is not trustworthy
for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) {
if (this_stats->is_flash || (this_stats - 1)->is_flash ||
(this_stats - 2)->is_flash)
continue;
if (this_stats->noise_var < 1.0) {
int found = 0;
// TODO(bohanli): consider expanding to two directions at the same time
for (next_stats = this_stats + 1; next_stats < last_stats; next_stats++) {
if (next_stats->is_flash || (next_stats - 1)->is_flash ||
(next_stats - 2)->is_flash || next_stats->noise_var < 1.0)
continue;
found = 1;
this_stats->noise_var = next_stats->noise_var;
break;
}
if (found)
continue;
for (next_stats = this_stats - 1; next_stats >= first_stats + 2;
next_stats--) {
if (next_stats->is_flash || (next_stats - 1)->is_flash ||
(next_stats - 2)->is_flash || next_stats->noise_var < 1.0)
continue;
this_stats->noise_var = next_stats->noise_var;
break;
}
}
}
// copy the noise if this is a flash
for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) {
if (this_stats->is_flash || (this_stats - 1)->is_flash ||
(this_stats - 2)->is_flash) {
int found = 0;
for (next_stats = this_stats + 1; next_stats < last_stats; next_stats++) {
if (next_stats->is_flash || (next_stats - 1)->is_flash ||
(next_stats - 2)->is_flash)
continue;
found = 1;
this_stats->noise_var = next_stats->noise_var;
break;
}
if (found)
continue;
for (next_stats = this_stats - 1; next_stats >= first_stats + 2;
next_stats--) {
if (next_stats->is_flash || (next_stats - 1)->is_flash ||
(next_stats - 2)->is_flash)
continue;
this_stats->noise_var = next_stats->noise_var;
break;
}
}
}
// if we are at the first 2 frames, copy the noise
for (this_stats = first_stats;
this_stats < first_stats + 2 && (first_stats + 2) < last_stats;
this_stats++) {
this_stats->noise_var = (first_stats + 2)->noise_var;
}
if (smooth_filter_noise(first_stats, last_stats) == -1) {
aom_internal_error(error_info, AOM_CODEC_MEM_ERROR,
"Error allocating buffers in smooth_filter_noise()");
}
}
// Estimate correlation coefficient of each frame with its previous frame.
static void estimate_coeff(FIRSTPASS_STATS *first_stats,
FIRSTPASS_STATS *last_stats) {
FIRSTPASS_STATS *this_stats;
for (this_stats = first_stats + 1; this_stats < last_stats; this_stats++) {
const double C =
sqrt(AOMMAX((this_stats - 1)->intra_error *
(this_stats->intra_error - this_stats->coded_error),
0.001));
const double cor_coeff =
C /
AOMMAX((this_stats - 1)->intra_error - this_stats->noise_var, 0.001);
this_stats->cor_coeff =
cor_coeff *
sqrt(AOMMAX((this_stats - 1)->intra_error - this_stats->noise_var,
0.001) /
AOMMAX(this_stats->intra_error - this_stats->noise_var, 0.001));
// clip correlation coefficient.
this_stats->cor_coeff = AOMMIN(AOMMAX(this_stats->cor_coeff, 0), 1);
}
first_stats->cor_coeff = 1.0;
}
void av1_get_second_pass_params(AV1_COMP *cpi,
EncodeFrameParams *
const frame_params,
unsigned int frame_flags) {
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
GF_GROUP *
const gf_group = &cpi->ppi->gf_group;
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
if (cpi->use_ducky_encode &&
cpi->ducky_encode_info.frame_info.gop_mode == DUCKY_ENCODE_GOP_MODE_RCL) {
frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index];
frame_params->show_frame =
!(gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE ||
gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE);
if (cpi->gf_frame_index == 0) {
av1_tf_info_reset(&cpi->ppi->tf_info);
av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group);
}
return;
}
const FIRSTPASS_STATS *
const start_pos = cpi->twopass_frame.stats_in;
int update_total_stats = 0;
if (is_stat_consumption_stage(cpi) && !cpi->twopass_frame.stats_in)
return;
// Check forced key frames.
const int frames_to_next_forced_key = detect_app_forced_key(cpi);
if (frames_to_next_forced_key == 0) {
rc->frames_to_key = 0;
frame_flags &= FRAMEFLAGS_KEY;
}
else if (frames_to_next_forced_key > 0 &&
frames_to_next_forced_key < rc->frames_to_key) {
rc->frames_to_key = frames_to_next_forced_key;
}
assert(cpi->twopass_frame.stats_in != NULL);
const int update_type = gf_group->update_type[cpi->gf_frame_index];
frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index];
if (cpi->gf_frame_index < gf_group->size && !(frame_flags & FRAMEFLAGS_KEY)) {
assert(cpi->gf_frame_index < gf_group->size);
setup_target_rate(cpi);
// If this is an arf frame then we dont want to read the stats file or
// advance the input pointer as we already have what we need.
if (update_type == ARF_UPDATE || update_type == INTNL_ARF_UPDATE) {
const FIRSTPASS_STATS *
const this_frame_ptr =
read_frame_stats(twopass, &cpi->twopass_frame,
gf_group->arf_src_offset[cpi->gf_frame_index]);
set_twopass_params_based_on_fp_stats(cpi, this_frame_ptr);
return;
}
}
if (oxcf->rc_cfg.mode == AOM_Q)
rc->active_worst_quality = oxcf->rc_cfg.cq_level;
if (cpi->gf_frame_index == gf_group->size) {
if (cpi->ppi->lap_enabled && cpi->ppi->p_rc.enable_scenecut_detection) {
const int num_frames_to_detect_scenecut = MAX_GF_LENGTH_LAP + 1;
const int frames_to_key = define_kf_interval(
cpi, &twopass->firstpass_info, num_frames_to_detect_scenecut,
/*search_start_idx=*/0);
if (frames_to_key != -1)
rc->frames_to_key = AOMMIN(rc->frames_to_key, frames_to_key);
}
}
FIRSTPASS_STATS this_frame;
av1_zero(this_frame);
// call above fn
if (is_stat_consumption_stage(cpi)) {
if (cpi->gf_frame_index < gf_group->size || rc->frames_to_key == 0) {
process_first_pass_stats(cpi, &this_frame);
update_total_stats = 1;
}
}
else {
rc->active_worst_quality = oxcf->rc_cfg.cq_level;
}
// Keyframe and section processing.
FIRSTPASS_STATS this_frame_copy;
this_frame_copy = this_frame;
if (rc->frames_to_key <= 0) {
assert(rc->frames_to_key == 0);
// Define next KF group and assign bits to it.
frame_params->frame_type = KEY_FRAME;
find_next_key_frame(cpi, &this_frame);
this_frame = this_frame_copy;
}
if (rc->frames_to_fwd_kf <= 0)
rc->frames_to_fwd_kf = oxcf->kf_cfg.fwd_kf_dist;
// Define a new GF/ARF group. (Should always enter here for key frames).
if (cpi->gf_frame_index == gf_group->size) {
av1_tf_info_reset(&cpi->ppi->tf_info);
#if CONFIG_BITRATE_ACCURACY && !CONFIG_THREE_PASS
vbr_rc_reset_gop_data(&cpi->vbr_rc_info);
#endif // CONFIG_BITRATE_ACCURACY
int max_gop_length =
(oxcf->gf_cfg.lag_in_frames >= 32)
? AOMMIN(MAX_GF_INTERVAL, oxcf->gf_cfg.lag_in_frames -
oxcf->algo_cfg.arnr_max_frames / 2)
: MAX_GF_LENGTH_LAP;
// Handle forward key frame when enabled.
if (oxcf->kf_cfg.fwd_kf_dist > 0)
max_gop_length = AOMMIN(rc->frames_to_fwd_kf + 1, max_gop_length);
// Use the provided gop size in low delay setting
if (oxcf->gf_cfg.lag_in_frames == 0) max_gop_length = rc->max_gf_interval;
// Limit the max gop length for the last gop in 1 pass setting.
max_gop_length = AOMMIN(max_gop_length, rc->frames_to_key);
// Identify regions if needed.
// TODO(bohanli): identify regions for all stats available.
if (rc->frames_since_key == 0 || rc->frames_since_key == 1 ||
(p_rc->frames_till_regions_update - rc->frames_since_key <
rc->frames_to_key &&
p_rc->frames_till_regions_update - rc->frames_since_key <
max_gop_length + 1)) {
// how many frames we can analyze from this frame
int rest_frames =
AOMMIN(rc->frames_to_key, MAX_FIRSTPASS_ANALYSIS_FRAMES);
rest_frames =
AOMMIN(rest_frames, (
int)(twopass->stats_buf_ctx->stats_in_end -
cpi->twopass_frame.stats_in +
(rc->frames_since_key == 0)));
p_rc->frames_till_regions_update = rest_frames;
int ret;
if (cpi->ppi->lap_enabled) {
mark_flashes(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end);
estimate_noise(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end, cpi->common.error);
estimate_coeff(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end);
ret = identify_regions(cpi->twopass_frame.stats_in, rest_frames,
(rc->frames_since_key == 0), p_rc->regions,
&p_rc->num_regions);
}
else {
ret = identify_regions(
cpi->twopass_frame.stats_in - (rc->frames_since_key == 0),
rest_frames, 0, p_rc->regions, &p_rc->num_regions);
}
if (ret == -1) {
aom_internal_error(cpi->common.error, AOM_CODEC_MEM_ERROR,
"Error allocating buffers in identify_regions");
}
}
int cur_region_idx =
find_regions_index(p_rc->regions, p_rc->num_regions,
rc->frames_since_key - p_rc->regions_offset);
if ((cur_region_idx >= 0 &&
p_rc->regions[cur_region_idx].type == SCENECUT_REGION) ||
rc->frames_since_key == 0) {
// If we start from a scenecut, then the last GOP's arf boost is not
// needed for this GOP.
cpi->ppi->gf_state.arf_gf_boost_lst = 0;
}
int need_gf_len = 1;
#if CONFIG_THREE_PASS
if (cpi->third_pass_ctx && oxcf->pass == AOM_RC_THIRD_PASS) {
// set up bitstream to read
if (!cpi->third_pass_ctx->input_file_name && oxcf->two_pass_output) {
cpi->third_pass_ctx->input_file_name = oxcf->two_pass_output;
}
av1_open_second_pass_log(cpi, 1);
THIRD_PASS_GOP_INFO *gop_info = &cpi->third_pass_ctx->gop_info;
// Read in GOP information from the second pass file.
av1_read_second_pass_gop_info(cpi->second_pass_log_stream, gop_info,
cpi->common.error);
#if CONFIG_BITRATE_ACCURACY
TPL_INFO *tpl_info;
AOM_CHECK_MEM_ERROR(cpi->common.error, tpl_info,
aom_malloc(
sizeof(*tpl_info)));
av1_read_tpl_info(tpl_info, cpi->second_pass_log_stream,
cpi->common.error);
aom_free(tpl_info);
#if CONFIG_THREE_PASS
// TODO(angiebird): Put this part into a func
cpi->vbr_rc_info.cur_gop_idx++;
#endif // CONFIG_THREE_PASS
#endif // CONFIG_BITRATE_ACCURACY
// Read in third_pass_info from the bitstream.
av1_set_gop_third_pass(cpi->third_pass_ctx);
// Read in per-frame info from second-pass encoding
av1_read_second_pass_per_frame_info(
cpi->second_pass_log_stream, cpi->third_pass_ctx->frame_info,
gop_info->num_frames, cpi->common.error);
p_rc->cur_gf_index = 0;
p_rc->gf_intervals[0] = cpi->third_pass_ctx->gop_info.gf_length;
need_gf_len = 0;
}
#endif // CONFIG_THREE_PASS
if (need_gf_len) {
// If we cannot obtain GF group length from second_pass_file
// TODO(jingning): Resolve the redundant calls here.
if (rc->intervals_till_gf_calculate_due == 0 || 1) {
calculate_gf_length(cpi, max_gop_length, MAX_NUM_GF_INTERVALS);
}
if (max_gop_length > 16 && oxcf->algo_cfg.enable_tpl_model &&
oxcf->gf_cfg.lag_in_frames >= 32 &&
cpi->sf.tpl_sf.gop_length_decision_method != 3) {
int this_idx = rc->frames_since_key +
p_rc->gf_intervals[p_rc->cur_gf_index] -
p_rc->regions_offset - 1;
int this_region =
find_regions_index(p_rc->regions, p_rc->num_regions, this_idx);
int next_region =
find_regions_index(p_rc->regions, p_rc->num_regions, this_idx + 1);
// TODO(angiebird): Figure out why this_region and next_region are -1 in
// unit test like AltRefFramePresenceTestLarge (aomedia:3134)
int is_last_scenecut =
p_rc->gf_intervals[p_rc->cur_gf_index] >= rc->frames_to_key ||
(this_region != -1 &&
p_rc->regions[this_region].type == SCENECUT_REGION) ||
(next_region != -1 &&
p_rc->regions[next_region].type == SCENECUT_REGION);
int ori_gf_int = p_rc->gf_intervals[p_rc->cur_gf_index];
if (p_rc->gf_intervals[p_rc->cur_gf_index] > 16 &&
rc->min_gf_interval <= 16) {
// The calculate_gf_length function is previously used with
// max_gop_length = 32 with look-ahead gf intervals.
define_gf_group(cpi, frame_params, 0);
av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group);
this_frame = this_frame_copy;
if (is_shorter_gf_interval_better(cpi, frame_params)) {
// A shorter gf interval is better.
// TODO(jingning): Remove redundant computations here.
max_gop_length = 16;
calculate_gf_length(cpi, max_gop_length, 1);
if (is_last_scenecut &&
(ori_gf_int - p_rc->gf_intervals[p_rc->cur_gf_index] < 4)) {
p_rc->gf_intervals[p_rc->cur_gf_index] = ori_gf_int;
}
}
}
}
}
define_gf_group(cpi, frame_params, 0);
if (gf_group->update_type[cpi->gf_frame_index] != ARF_UPDATE &&
rc->frames_since_key > 0)
process_first_pass_stats(cpi, &this_frame);
define_gf_group(cpi, frame_params, 1);
#if CONFIG_THREE_PASS
// write gop info if needed for third pass. Per-frame info is written after
// each frame is encoded.
av1_write_second_pass_gop_info(cpi);
#endif // CONFIG_THREE_PASS
av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group);
rc->frames_till_gf_update_due = p_rc->baseline_gf_interval;
assert(cpi->gf_frame_index == 0);
#if ARF_STATS_OUTPUT
{
FILE *fpfile;
fpfile = fopen(
"arf.stt",
"a");
++arf_count;
fprintf(fpfile,
"%10d %10d %10d %10d %10d\n",
cpi->common.current_frame.frame_number,
rc->frames_till_gf_update_due, cpi->ppi->p_rc.kf_boost, arf_count,
p_rc->gfu_boost);
fclose(fpfile);
}
#endif
}
assert(cpi->gf_frame_index < gf_group->size);
if (gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE ||
gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE) {
reset_fpf_position(&cpi->twopass_frame, start_pos);
const FIRSTPASS_STATS *
const this_frame_ptr =
read_frame_stats(twopass, &cpi->twopass_frame,
gf_group->arf_src_offset[cpi->gf_frame_index]);
set_twopass_params_based_on_fp_stats(cpi, this_frame_ptr);
}
else {
// Back up this frame's stats for updating total stats during post encode.
cpi->twopass_frame.this_frame = update_total_stats ? start_pos : NULL;
}
frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index];
setup_target_rate(cpi);
}
void av1_init_second_pass(AV1_COMP *cpi) {
const AV1EncoderConfig *
const oxcf = &cpi->oxcf;
TWO_PASS *
const twopass = &cpi->ppi->twopass;
FRAME_INFO *
const frame_info = &cpi->frame_info;
double frame_rate;
FIRSTPASS_STATS *stats;
if (!twopass->stats_buf_ctx->stats_in_end)
return;
mark_flashes(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end);
estimate_noise(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end, cpi->common.error);
estimate_coeff(twopass->stats_buf_ctx->stats_in_start,
twopass->stats_buf_ctx->stats_in_end);
stats = twopass->stats_buf_ctx->total_stats;
*stats = *twopass->stats_buf_ctx->stats_in_end;
*twopass->stats_buf_ctx->total_left_stats = *stats;
frame_rate = 10000000.0 * stats->count / stats->duration;
// Each frame can have a different duration, as the frame rate in the source
// isn't guaranteed to be constant. The frame rate prior to the first frame
// encoded in the second pass is a guess. However, the sum duration is not.
// It is calculated based on the actual durations of all frames from the
// first pass.
av1_new_framerate(cpi, frame_rate);
twopass->bits_left =
(int64_t)(stats->duration * oxcf->rc_cfg.target_bandwidth / 10000000.0);
#if CONFIG_BITRATE_ACCURACY
av1_vbr_rc_init(&cpi->vbr_rc_info, twopass->bits_left,
(
int)round(stats->count));
#endif
#if CONFIG_RATECTRL_LOG
rc_log_init(&cpi->rc_log);
#endif
// This variable monitors how far behind the second ref update is lagging.
twopass->sr_update_lag = 1;
// Scan the first pass file and calculate a modified total error based upon
// the bias/power function used to allocate bits.
{
const double avg_error =
stats->coded_error / DOUBLE_DIVIDE_CHECK(stats->count);
const FIRSTPASS_STATS *s = cpi->twopass_frame.stats_in;
double modified_error_total = 0.0;
twopass->modified_error_min =
(avg_error * oxcf->rc_cfg.vbrmin_section) / 100;
twopass->modified_error_max =
(avg_error * oxcf->rc_cfg.vbrmax_section) / 100;
while (s < twopass->stats_buf_ctx->stats_in_end) {
modified_error_total +=
calculate_modified_err(frame_info, twopass, oxcf, s);
++s;
}
twopass->modified_error_left = modified_error_total;
}
// Reset the vbr bits off target counters
cpi->ppi->p_rc.vbr_bits_off_target = 0;
cpi->ppi->p_rc.vbr_bits_off_target_fast = 0;
cpi->ppi->p_rc.rate_error_estimate = 0;
// Static sequence monitor variables.
twopass->kf_zeromotion_pct = 100;
twopass->last_kfgroup_zeromotion_pct = 100;
// Initialize bits per macro_block estimate correction factor.
twopass->bpm_factor = 1.0;
// Initialize actual and target bits counters for ARF groups so that
// at the start we have a neutral bpm adjustment.
twopass->rolling_arf_group_target_bits = 1;
twopass->rolling_arf_group_actual_bits = 1;
}
void av1_init_single_pass_lap(AV1_COMP *cpi) {
TWO_PASS *
const twopass = &cpi->ppi->twopass;
if (!twopass->stats_buf_ctx->stats_in_end)
return;
// This variable monitors how far behind the second ref update is lagging.
twopass->sr_update_lag = 1;
twopass->bits_left = 0;
twopass->modified_error_min = 0.0;
twopass->modified_error_max = 0.0;
twopass->modified_error_left = 0.0;
// Reset the vbr bits off target counters
cpi->ppi->p_rc.vbr_bits_off_target = 0;
cpi->ppi->p_rc.vbr_bits_off_target_fast = 0;
cpi->ppi->p_rc.rate_error_estimate = 0;
// Static sequence monitor variables.
twopass->kf_zeromotion_pct = 100;
twopass->last_kfgroup_zeromotion_pct = 100;
// Initialize bits per macro_block estimate correction factor.
twopass->bpm_factor = 1.0;
// Initialize actual and target bits counters for ARF groups so that
// at the start we have a neutral bpm adjustment.
twopass->rolling_arf_group_target_bits = 1;
twopass->rolling_arf_group_actual_bits = 1;
}
#define MINQ_ADJ_LIMIT 48
#define MINQ_ADJ_LIMIT_CQ 20
#define HIGH_UNDERSHOOT_RATIO 2
void av1_twopass_postencode_update(AV1_COMP *cpi) {
TWO_PASS *
const twopass = &cpi->ppi->twopass;
RATE_CONTROL *
const rc = &cpi->rc;
PRIMARY_RATE_CONTROL *
const p_rc = &cpi->ppi->p_rc;
const RateControlCfg *
const rc_cfg = &cpi->oxcf.rc_cfg;
// Increment the stats_in pointer.
if (is_stat_consumption_stage(cpi) &&
!(cpi->use_ducky_encode && cpi->ducky_encode_info.frame_info.gop_mode ==
DUCKY_ENCODE_GOP_MODE_RCL) &&
(cpi->gf_frame_index < cpi->ppi->gf_group.size ||
rc->frames_to_key == 0)) {
const int update_type = cpi->ppi->gf_group.update_type[cpi->gf_frame_index];
if (update_type != ARF_UPDATE && update_type != INTNL_ARF_UPDATE) {
FIRSTPASS_STATS this_frame;
assert(cpi->twopass_frame.stats_in >
twopass->stats_buf_ctx->stats_in_start);
--cpi->twopass_frame.stats_in;
if (cpi->ppi->lap_enabled) {
input_stats_lap(twopass, &cpi->twopass_frame, &this_frame);
}
else {
input_stats(twopass, &cpi->twopass_frame, &this_frame);
}
}
else if (cpi->ppi->lap_enabled) {
cpi->twopass_frame.stats_in = twopass->stats_buf_ctx->stats_in_start;
}
}
// VBR correction is done through rc->vbr_bits_off_target. Based on the
// sign of this value, a limited % adjustment is made to the target rate
// of subsequent frames, to try and push it back towards 0. This method
// is designed to prevent extreme behaviour at the end of a clip
// or group of frames.
p_rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size;
twopass->bits_left = AOMMAX(twopass->bits_left - rc->base_frame_target, 0);
if (cpi->do_update_vbr_bits_off_target_fast) {
// Subtract current frame's fast_extra_bits.
p_rc->vbr_bits_off_target_fast -= rc->frame_level_fast_extra_bits;
rc->frame_level_fast_extra_bits = 0;
}
// Target vs actual bits for this arf group.
if (twopass->rolling_arf_group_target_bits >
INT_MAX - rc->base_frame_target) {
twopass->rolling_arf_group_target_bits = INT_MAX;
}
else {
twopass->rolling_arf_group_target_bits += rc->base_frame_target;
}
twopass->rolling_arf_group_actual_bits += rc->projected_frame_size;
// Calculate the pct rc error.
if (p_rc->total_actual_bits) {
p_rc->rate_error_estimate =
(
int)((p_rc->vbr_bits_off_target * 100) / p_rc->total_actual_bits);
p_rc->rate_error_estimate = clamp(p_rc->rate_error_estimate, -100, 100);
}
else {
p_rc->rate_error_estimate = 0;
}
#if CONFIG_FPMT_TEST
/* The variables temp_vbr_bits_off_target, temp_bits_left,
* temp_rolling_arf_group_target_bits, temp_rolling_arf_group_actual_bits
* temp_rate_error_estimate are introduced for quality simulation purpose,
* it retains the value previous to the parallel encode frames. The
* variables are updated based on the update flag.
*
* If there exist show_existing_frames between parallel frames, then to
* retain the temp state do not update it. */
const int simulate_parallel_frame =
cpi->ppi->fpmt_unit_test_cfg == PARALLEL_SIMULATION_ENCODE;
int show_existing_between_parallel_frames =
(cpi->ppi->gf_group.update_type[cpi->gf_frame_index] ==
INTNL_OVERLAY_UPDATE &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index + 1] == 2);
if (cpi->do_frame_data_update && !show_existing_between_parallel_frames &&
simulate_parallel_frame) {
cpi->ppi->p_rc.temp_vbr_bits_off_target = p_rc->vbr_bits_off_target;
cpi->ppi->p_rc.temp_bits_left = twopass->bits_left;
cpi->ppi->p_rc.temp_rolling_arf_group_target_bits =
twopass->rolling_arf_group_target_bits;
cpi->ppi->p_rc.temp_rolling_arf_group_actual_bits =
twopass->rolling_arf_group_actual_bits;
cpi->ppi->p_rc.temp_rate_error_estimate = p_rc->rate_error_estimate;
}
#endif
// Update the active best quality pyramid.
if (!rc->is_src_frame_alt_ref) {
const int pyramid_level =
cpi->ppi->gf_group.layer_depth[cpi->gf_frame_index];
int i;
for (i = pyramid_level; i <= MAX_ARF_LAYERS; ++i) {
p_rc->active_best_quality[i] = cpi->common.quant_params.base_qindex;
#if CONFIG_TUNE_VMAF
if (cpi->vmaf_info.original_qindex != -1 &&
(cpi->oxcf.tune_cfg.tuning >= AOM_TUNE_VMAF_WITH_PREPROCESSING &&
cpi->oxcf.tune_cfg.tuning <= AOM_TUNE_VMAF_NEG_MAX_GAIN)) {
p_rc->active_best_quality[i] = cpi->vmaf_info.original_qindex;
}
#endif
}
}
#if 0
{
AV1_COMMON *cm = &cpi->common;
FILE *fpfile;
fpfile = fopen(
"details.stt",
"a");
fprintf(fpfile,
"%10d %10d %10d %10" PRId64
" %10" PRId64
" %10d %10d %10d %10.4lf %10.4lf %10.4lf %10.4lf\n",
cm->current_frame.frame_number, rc->base_frame_target,
rc->projected_frame_size, rc->total_actual_bits,
rc->vbr_bits_off_target, p_rc->rate_error_estimate,
twopass->rolling_arf_group_target_bits,
twopass->rolling_arf_group_actual_bits,
(
double)twopass->rolling_arf_group_actual_bits /
(
double)twopass->rolling_arf_group_target_bits,
twopass->bpm_factor,
av1_convert_qindex_to_q(cpi->common.quant_params.base_qindex,
cm->seq_params->bit_depth),
av1_convert_qindex_to_q(rc->active_worst_quality,
cm->seq_params->bit_depth));
fclose(fpfile);
}
#endif
if (cpi->common.current_frame.frame_type != KEY_FRAME) {
twopass->kf_group_bits -= rc->base_frame_target;
twopass->last_kfgroup_zeromotion_pct = twopass->kf_zeromotion_pct;
}
twopass->kf_group_bits = AOMMAX(twopass->kf_group_bits, 0);
// If the rate control is drifting consider adjustment to min or maxq.
if ((rc_cfg->mode != AOM_Q) && !cpi->rc.is_src_frame_alt_ref &&
(p_rc->rolling_target_bits > 0)) {
int minq_adj_limit;
int maxq_adj_limit;
minq_adj_limit =
(rc_cfg->mode == AOM_CQ ? MINQ_ADJ_LIMIT_CQ : MINQ_ADJ_LIMIT);
maxq_adj_limit = (rc->worst_quality - rc->active_worst_quality);
// Undershoot
if ((rc_cfg->under_shoot_pct < 100) &&
(p_rc->rolling_actual_bits < p_rc->rolling_target_bits)) {
int pct_error =
((p_rc->rolling_target_bits - p_rc->rolling_actual_bits) * 100) /
p_rc->rolling_target_bits;
if ((pct_error >= rc_cfg->under_shoot_pct) &&
(p_rc->rate_error_estimate > 0)) {
twopass->extend_minq += 1;
twopass->extend_maxq -= 1;
}
// Overshoot
}
else if ((rc_cfg->over_shoot_pct < 100) &&
(p_rc->rolling_actual_bits > p_rc->rolling_target_bits)) {
int pct_error =
((p_rc->rolling_actual_bits - p_rc->rolling_target_bits) * 100) /
p_rc->rolling_target_bits;
pct_error = clamp(pct_error, 0, 100);
if ((pct_error >= rc_cfg->over_shoot_pct) &&
(p_rc->rate_error_estimate < 0)) {
twopass->extend_maxq += 1;
twopass->extend_minq -= 1;
}
}
twopass->extend_minq =
clamp(twopass->extend_minq, -minq_adj_limit, minq_adj_limit);
twopass->extend_maxq = clamp(twopass->extend_maxq, 0, maxq_adj_limit);
// If there is a big and undexpected undershoot then feed the extra
// bits back in quickly. One situation where this may happen is if a
// frame is unexpectedly almost perfectly predicted by the ARF or GF
// but not very well predcited by the previous frame.
if (!frame_is_kf_gf_arf(cpi) && !cpi->rc.is_src_frame_alt_ref) {
int fast_extra_thresh = rc->base_frame_target / HIGH_UNDERSHOOT_RATIO;
if (rc->projected_frame_size < fast_extra_thresh) {
p_rc->vbr_bits_off_target_fast +=
fast_extra_thresh - rc->projected_frame_size;
p_rc->vbr_bits_off_target_fast =
AOMMIN(p_rc->vbr_bits_off_target_fast,
(4 * (int64_t)rc->avg_frame_bandwidth));
}
}
#if CONFIG_FPMT_TEST
if (cpi->do_frame_data_update && !show_existing_between_parallel_frames &&
simulate_parallel_frame) {
cpi->ppi->p_rc.temp_vbr_bits_off_target_fast =
p_rc->vbr_bits_off_target_fast;
cpi->ppi->p_rc.temp_extend_minq = twopass->extend_minq;
cpi->ppi->p_rc.temp_extend_maxq = twopass->extend_maxq;
}
#endif
}
// Update the frame probabilities obtained from parallel encode frames
FrameProbInfo *
const frame_probs = &cpi->ppi->frame_probs;
#if CONFIG_FPMT_TEST
/* The variable temp_active_best_quality is introduced only for quality
* simulation purpose, it retains the value previous to the parallel
* encode frames. The variable is updated based on the update flag.
*
* If there exist show_existing_frames between parallel frames, then to
* retain the temp state do not update it. */
if (cpi->do_frame_data_update && !show_existing_between_parallel_frames &&
simulate_parallel_frame) {
int i;
const int pyramid_level =
cpi->ppi->gf_group.layer_depth[cpi->gf_frame_index];
if (!rc->is_src_frame_alt_ref) {
for (i = pyramid_level; i <= MAX_ARF_LAYERS; ++i)
cpi->ppi->p_rc.temp_active_best_quality[i] =
p_rc->active_best_quality[i];
}
}
// Update the frame probabilities obtained from parallel encode frames
FrameProbInfo *
const temp_frame_probs_simulation =
simulate_parallel_frame ? &cpi->ppi->temp_frame_probs_simulation
: frame_probs;
FrameProbInfo *
const temp_frame_probs =
simulate_parallel_frame ? &cpi->ppi->temp_frame_probs : NULL;
#endif
int i, j, loop;
// Sequentially do average on temp_frame_probs_simulation which holds
// probabilities of last frame before parallel encode
for (loop = 0; loop <= cpi->num_frame_recode; loop++) {
// Sequentially update tx_type_probs
if (cpi->do_update_frame_probs_txtype[loop] &&
(cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0)) {
const FRAME_UPDATE_TYPE update_type =
get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index);
for (i = 0; i < TX_SIZES_ALL; i++) {
int left = 1024;
for (j = TX_TYPES - 1; j >= 0; j--) {
const int new_prob =
cpi->frame_new_probs[loop].tx_type_probs[update_type][i][j];
#if CONFIG_FPMT_TEST
int prob =
(temp_frame_probs_simulation->tx_type_probs[update_type][i][j] +
new_prob) >>
1;
left -= prob;
if (j == 0) prob += left;
temp_frame_probs_simulation->tx_type_probs[update_type][i][j] = prob;
#else
int prob =
(frame_probs->tx_type_probs[update_type][i][j] + new_prob) >> 1;
left -= prob;
if (j == 0) prob += left;
frame_probs->tx_type_probs[update_type][i][j] = prob;
#endif
}
}
}
// Sequentially update obmc_probs
if (cpi->do_update_frame_probs_obmc[loop] &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) {
const FRAME_UPDATE_TYPE update_type =
get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index);
for (i = 0; i < BLOCK_SIZES_ALL; i++) {
const int new_prob =
cpi->frame_new_probs[loop].obmc_probs[update_type][i];
#if CONFIG_FPMT_TEST
temp_frame_probs_simulation->obmc_probs[update_type][i] =
(temp_frame_probs_simulation->obmc_probs[update_type][i] +
new_prob) >>
1;
#else
frame_probs->obmc_probs[update_type][i] =
(frame_probs->obmc_probs[update_type][i] + new_prob) >> 1;
#endif
}
}
// Sequentially update warped_probs
if (cpi->do_update_frame_probs_warp[loop] &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) {
const FRAME_UPDATE_TYPE update_type =
get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index);
const int new_prob = cpi->frame_new_probs[loop].warped_probs[update_type];
#if CONFIG_FPMT_TEST
temp_frame_probs_simulation->warped_probs[update_type] =
(temp_frame_probs_simulation->warped_probs[update_type] + new_prob) >>
1;
#else
frame_probs->warped_probs[update_type] =
(frame_probs->warped_probs[update_type] + new_prob) >> 1;
#endif
}
// Sequentially update switchable_interp_probs
if (cpi->do_update_frame_probs_interpfilter[loop] &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) {
const FRAME_UPDATE_TYPE update_type =
get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index);
for (i = 0; i < SWITCHABLE_FILTER_CONTEXTS; i++) {
int left = 1536;
for (j = SWITCHABLE_FILTERS - 1; j >= 0; j--) {
const int new_prob = cpi->frame_new_probs[loop]
.switchable_interp_probs[update_type][i][j];
#if CONFIG_FPMT_TEST
int prob = (temp_frame_probs_simulation
->switchable_interp_probs[update_type][i][j] +
new_prob) >>
1;
left -= prob;
if (j == 0) prob += left;
temp_frame_probs_simulation
->switchable_interp_probs[update_type][i][j] = prob;
#else
int prob = (frame_probs->switchable_interp_probs[update_type][i][j] +
new_prob) >>
1;
left -= prob;
if (j == 0) prob += left;
frame_probs->switchable_interp_probs[update_type][i][j] = prob;
#endif
}
}
}
}
#if CONFIG_FPMT_TEST
// Copying temp_frame_probs_simulation to temp_frame_probs based on
// the flag
if (cpi->do_frame_data_update &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0 &&
simulate_parallel_frame) {
for (
int update_type_idx = 0; update_type_idx < FRAME_UPDATE_TYPES;
update_type_idx++) {
for (i = 0; i < BLOCK_SIZES_ALL; i++) {
temp_frame_probs->obmc_probs[update_type_idx][i] =
temp_frame_probs_simulation->obmc_probs[update_type_idx][i];
}
temp_frame_probs->warped_probs[update_type_idx] =
temp_frame_probs_simulation->warped_probs[update_type_idx];
for (i = 0; i < TX_SIZES_ALL; i++) {
for (j = 0; j < TX_TYPES; j++) {
temp_frame_probs->tx_type_probs[update_type_idx][i][j] =
temp_frame_probs_simulation->tx_type_probs[update_type_idx][i][j];
}
}
for (i = 0; i < SWITCHABLE_FILTER_CONTEXTS; i++) {
for (j = 0; j < SWITCHABLE_FILTERS; j++) {
temp_frame_probs->switchable_interp_probs[update_type_idx][i][j] =
temp_frame_probs_simulation
->switchable_interp_probs[update_type_idx][i][j];
}
}
}
}
#endif
// Update framerate obtained from parallel encode frames
if (cpi->common.show_frame &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0)
cpi->framerate = cpi->new_framerate;
#if CONFIG_FPMT_TEST
// SIMULATION PURPOSE
int show_existing_between_parallel_frames_cndn =
(cpi->ppi->gf_group.update_type[cpi->gf_frame_index] ==
INTNL_OVERLAY_UPDATE &&
cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index + 1] == 2);
if (cpi->common.show_frame && !show_existing_between_parallel_frames_cndn &&
cpi->do_frame_data_update && simulate_parallel_frame)
cpi->temp_framerate = cpi->framerate;
#endif
}
