/*
* Copyright (c) 2016, 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.
*/
#include <math.h>
#include <stdlib.h>
#include "config/aom_dsp_rtcd.h"
#include "config/av1_rtcd.h"
#include "av1/common/cdef.h"
/*
This is Cdef_Directions (section 7.15.3) with 2 padding entries at the
beginning and end of the table. The cdef direction range is [0, 7] and the
first index is offset +/-2. This removes the need to constrain the first
index to the same range using e.g., & 7.
*/
DECLARE_ALIGNED(
16,
static const int, cdef_directions_padded[
12][
2]) = {
/* Padding: cdef_directions[6] */
{
1 * CDEF_BSTRIDE +
0,
2 * CDEF_BSTRIDE +
0 },
/* Padding: cdef_directions[7] */
{
1 * CDEF_BSTRIDE +
0,
2 * CDEF_BSTRIDE -
1 },
/* Begin cdef_directions */
{ -
1 * CDEF_BSTRIDE +
1, -
2 * CDEF_BSTRIDE +
2 },
{
0 * CDEF_BSTRIDE +
1, -
1 * CDEF_BSTRIDE +
2 },
{
0 * CDEF_BSTRIDE +
1,
0 * CDEF_BSTRIDE +
2 },
{
0 * CDEF_BSTRIDE +
1,
1 * CDEF_BSTRIDE +
2 },
{
1 * CDEF_BSTRIDE +
1,
2 * CDEF_BSTRIDE +
2 },
{
1 * CDEF_BSTRIDE +
0,
2 * CDEF_BSTRIDE +
1 },
{
1 * CDEF_BSTRIDE +
0,
2 * CDEF_BSTRIDE +
0 },
{
1 * CDEF_BSTRIDE +
0,
2 * CDEF_BSTRIDE -
1 },
/* End cdef_directions */
/* Padding: cdef_directions[0] */
{ -
1 * CDEF_BSTRIDE +
1, -
2 * CDEF_BSTRIDE +
2 },
/* Padding: cdef_directions[1] */
{
0 * CDEF_BSTRIDE +
1, -
1 * CDEF_BSTRIDE +
2 },
};
const int (*
const cdef_directions)[
2] = cdef_directions_padded +
2;
/* Detect direction. 0 means 45-degree up-right, 2 is horizontal, and so on.
The search minimizes the weighted variance along all the lines in a
particular direction, i.e. the squared error between the input and a
"predicted" block where each pixel is replaced by the average along a line
in a particular direction. Since each direction have the same sum(x^2) term,
that term is never computed. See Section 2, step 2, of:
http://jmvalin.ca/notes/intra_paint.pdf */
int cdef_find_dir_c(
const uint16_t *img,
int stride, int32_t *var,
int coeff_shift) {
int i;
int32_t cost[
8] = {
0 };
int partial[
8][
15] = { {
0 } };
int32_t best_cost =
0;
int best_dir =
0;
/* Instead of dividing by n between 2 and 8, we multiply by 3*5*7*8/n.
The output is then 840 times larger, but we don't care for finding
the max. */
static const int div_table[] = {
0,
840,
420,
280,
210,
168,
140,
120,
105 };
for (i =
0; i <
8; i++) {
int j;
for (j =
0; j <
8; j++) {
int x;
/* We subtract 128 here to reduce the maximum range of the squared
partial sums. */
x = (img[i * stride + j] >> coeff_shift) -
128;
partial[
0][i + j] += x;
partial[
1][i + j /
2] += x;
partial[
2][i] += x;
partial[
3][
3 + i - j /
2] += x;
partial[
4][
7 + i - j] += x;
partial[
5][
3 - i /
2 + j] += x;
partial[
6][j] += x;
partial[
7][i /
2 + j] += x;
}
}
for (i =
0; i <
8; i++) {
cost[
2] += partial[
2][i] * partial[
2][i];
cost[
6] += partial[
6][i] * partial[
6][i];
}
cost[
2] *= div_table[
8];
cost[
6] *= div_table[
8];
for (i =
0; i <
7; i++) {
cost[
0] += (partial[
0][i] * partial[
0][i] +
partial[
0][
14 - i] * partial[
0][
14 - i]) *
div_table[i +
1];
cost[
4] += (partial[
4][i] * partial[
4][i] +
partial[
4][
14 - i] * partial[
4][
14 - i]) *
div_table[i +
1];
}
cost[
0] += partial[
0][
7] * partial[
0][
7] * div_table[
8];
cost[
4] += partial[
4][
7] * partial[
4][
7] * div_table[
8];
for (i =
1; i <
8; i +=
2) {
int j;
for (j =
0; j <
4 +
1; j++) {
cost[i] += partial[i][
3 + j] * partial[i][
3 + j];
}
cost[i] *= div_table[
8];
for (j =
0; j <
4 -
1; j++) {
cost[i] += (partial[i][j] * partial[i][j] +
partial[i][
10 - j] * partial[i][
10 - j]) *
div_table[
2 * j +
2];
}
}
for (i =
0; i <
8; i++) {
if (cost[i] > best_cost) {
best_cost = cost[i];
best_dir = i;
}
}
/* Difference between the optimal variance and the variance along the
orthogonal direction. Again, the sum(x^2) terms cancel out. */
*var = best_cost - cost[(best_dir +
4) &
7];
/* We'd normally divide by 840, but dividing by 1024 is close enough
for what we're going to do with this. */
*var >>=
10;
return best_dir;
}
void cdef_find_dir_dual_c(
const uint16_t *img1,
const uint16_t *img2,
int stride, int32_t *var1, int32_t *var2,
int coeff_shift,
int *out1,
int *out2) {
*out1 = cdef_find_dir_c(img1, stride, var1, coeff_shift);
*out2 = cdef_find_dir_c(img2, stride, var2, coeff_shift);
}
const int cdef_pri_taps[
2][
2] = { {
4,
2 }, {
3,
3 } };
const int cdef_sec_taps[
2] = {
2,
1 };
/* Smooth in the direction detected. */
static void cdef_filter_block_internal(
uint8_t *dst8, uint16_t *dst16,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height,
int enable_primary,
int enable_secondary) {
const int clipping_required = (enable_primary && enable_secondary);
int i, j, k;
const int s = CDEF_BSTRIDE;
const int *pri_taps = cdef_pri_taps[(pri_strength >> coeff_shift) &
1];
const int *sec_taps = cdef_sec_taps;
for (i =
0; i < block_height; i++) {
for (j =
0; j < block_width; j++) {
int16_t sum =
0;
int16_t y;
int16_t x = in[i * s + j];
int max = x;
int min = x;
for (k =
0; k <
2; k++) {
if (enable_primary) {
int16_t p0 = in[i * s + j + cdef_directions[dir][k]];
int16_t p1 = in[i * s + j - cdef_directions[dir][k]];
sum += pri_taps[k] * constrain(p0 - x, pri_strength, pri_damping);
sum += pri_taps[k] * constrain(p1 - x, pri_strength, pri_damping);
if (clipping_required) {
if (p0 != CDEF_VERY_LARGE) max = AOMMAX(p0, max);
if (p1 != CDEF_VERY_LARGE) max = AOMMAX(p1, max);
min = AOMMIN(p0, min);
min = AOMMIN(p1, min);
}
}
if (enable_secondary) {
int16_t s0 = in[i * s + j + cdef_directions[dir +
2][k]];
int16_t s1 = in[i * s + j - cdef_directions[dir +
2][k]];
int16_t s2 = in[i * s + j + cdef_directions[dir -
2][k]];
int16_t s3 = in[i * s + j - cdef_directions[dir -
2][k]];
if (clipping_required) {
if (s0 != CDEF_VERY_LARGE) max = AOMMAX(s0, max);
if (s1 != CDEF_VERY_LARGE) max = AOMMAX(s1, max);
if (s2 != CDEF_VERY_LARGE) max = AOMMAX(s2, max);
if (s3 != CDEF_VERY_LARGE) max = AOMMAX(s3, max);
min = AOMMIN(s0, min);
min = AOMMIN(s1, min);
min = AOMMIN(s2, min);
min = AOMMIN(s3, min);
}
sum += sec_taps[k] * constrain(s0 - x, sec_strength, sec_damping);
sum += sec_taps[k] * constrain(s1 - x, sec_strength, sec_damping);
sum += sec_taps[k] * constrain(s2 - x, sec_strength, sec_damping);
sum += sec_taps[k] * constrain(s3 - x, sec_strength, sec_damping);
}
}
y = ((int16_t)x + ((
8 + sum - (sum <
0)) >>
4));
if (clipping_required) {
y = clamp(y, min, max);
}
if (dst8)
dst8[i * dstride + j] = (uint8_t)y;
else
dst16[i * dstride + j] = (uint16_t)y;
}
}
}
void cdef_filter_8_0_c(
void *dst8,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal((uint8_t *)dst8, NULL, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/1, /*enable_secondary=*/1);
}
void cdef_filter_8_1_c(
void *dst8,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal((uint8_t *)dst8, NULL, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/1, /*enable_secondary=*/0);
}
void cdef_filter_8_2_c(
void *dst8,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal((uint8_t *)dst8, NULL, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/0, /*enable_secondary=*/1);
}
void cdef_filter_8_3_c(
void *dst8,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal((uint8_t *)dst8, NULL, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/0, /*enable_secondary=*/0);
}
void cdef_filter_16_0_c(
void *dst16,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal(NULL, (uint16_t *)dst16, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/1, /*enable_secondary=*/1);
}
void cdef_filter_16_1_c(
void *dst16,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal(NULL, (uint16_t *)dst16, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/1, /*enable_secondary=*/0);
}
void cdef_filter_16_2_c(
void *dst16,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal(NULL, (uint16_t *)dst16, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/0, /*enable_secondary=*/1);
}
void cdef_filter_16_3_c(
void *dst16,
int dstride,
const uint16_t *in,
int pri_strength,
int sec_strength,
int dir,
int pri_damping,
int sec_damping,
int coeff_shift,
int block_width,
int block_height) {
cdef_filter_block_internal(NULL, (uint16_t *)dst16, dstride, in, pri_strength,
sec_strength, dir, pri_damping, sec_damping,
coeff_shift, block_width, block_height,
/*enable_primary=*/0, /*enable_secondary=*/0);
}
/* Compute the primary filter strength for an 8x8 block based on the
directional variance difference. A high variance difference means
that we have a highly directional pattern (e.g. a high contrast
edge), so we can apply more deringing. A low variance means that we
either have a low contrast edge, or a non-directional texture, so
we want to be careful not to blur. */
static inline int adjust_strength(
int strength, int32_t var) {
const int i = var >>
6 ? AOMMIN(get_msb(var >>
6),
12) :
0;
/* We use the variance of 8x8 blocks to adjust the strength. */
return var ? (strength * (
4 + i) +
8) >>
4 :
0;
}
static inline void aom_cdef_find_dir(
const uint16_t *in, cdef_list *dlist,
int var[CDEF_NBLOCKS][CDEF_NBLOCKS],
int cdef_count,
int coeff_shift,
int dir[CDEF_NBLOCKS][CDEF_NBLOCKS]) {
int bi;
// Find direction of two 8x8 blocks together.
for (bi =
0; bi < cdef_count -
1; bi +=
2) {
const int by = dlist[bi].by;
const int bx = dlist[bi].bx;
const int by2 = dlist[bi +
1].by;
const int bx2 = dlist[bi +
1].bx;
const int pos1 =
8 * by * CDEF_BSTRIDE +
8 * bx;
const int pos2 =
8 * by2 * CDEF_BSTRIDE +
8 * bx2;
cdef_find_dir_dual(&in[pos1], &in[pos2], CDEF_BSTRIDE, &var[by][bx],
&var[by2][bx2], coeff_shift, &dir[by][bx],
&dir[by2][bx2]);
}
// Process remaining 8x8 blocks here. One 8x8 at a time.
if (cdef_count %
2) {
const int by = dlist[bi].by;
const int bx = dlist[bi].bx;
dir[by][bx] = cdef_find_dir(&in[
8 * by * CDEF_BSTRIDE +
8 * bx],
CDEF_BSTRIDE, &var[by][bx], coeff_shift);
}
}
void av1_cdef_filter_fb(uint8_t *dst8, uint16_t *dst16,
int dstride,
const uint16_t *in,
int xdec,
int ydec,
int dir[CDEF_NBLOCKS][CDEF_NBLOCKS],
int *dirinit,
int var[CDEF_NBLOCKS][CDEF_NBLOCKS],
int pli,
cdef_list *dlist,
int cdef_count,
int level,
int sec_strength,
int damping,
int coeff_shift) {
int bi;
int bx;
int by;
const int pri_strength = level << coeff_shift;
sec_strength <<= coeff_shift;
damping += coeff_shift - (pli != AOM_PLANE_Y);
const int bw_log2 =
3 - xdec;
const int bh_log2 =
3 - ydec;
if (dirinit && pri_strength ==
0 && sec_strength ==
0) {
// If we're here, both primary and secondary strengths are 0, and
// we still haven't written anything to y[] yet, so we just copy
// the input to y[]. This is necessary only for av1_cdef_search()
// and only av1_cdef_search() sets dirinit.
for (bi =
0; bi < cdef_count; bi++) {
by = dlist[bi].by;
bx = dlist[bi].bx;
// TODO(stemidts/jmvalin): SIMD optimisations
for (
int iy =
0; iy <
1 << bh_log2; iy++) {
memcpy(&dst16[(bi << (bw_log2 + bh_log2)) + (iy << bw_log2)],
&in[((by << bh_log2) + iy) * CDEF_BSTRIDE + (bx << bw_log2)],
((size_t)
1 << bw_log2) *
sizeof(*dst16));
}
}
return;
}
if (pli ==
0) {
if (!dirinit || !*dirinit) {
aom_cdef_find_dir(in, dlist, var, cdef_count, coeff_shift, dir);
if (dirinit) *dirinit =
1;
}
}
if (pli ==
1 && xdec != ydec) {
for (bi =
0; bi < cdef_count; bi++) {
static const int conv422[
8] = {
7,
0,
2,
4,
5,
6,
6,
6 };
static const int conv440[
8] = {
1,
2,
2,
2,
3,
4,
6,
0 };
by = dlist[bi].by;
bx = dlist[bi].bx;
dir[by][bx] = (xdec ? conv422 : conv440)[dir[by][bx]];
}
}
if (dst8) {
const int block_width =
8 >> xdec;
const int block_height =
8 >> ydec;
/*
* strength_index == 0 : enable_primary = 1, enable_secondary = 1
* strength_index == 1 : enable_primary = 1, enable_secondary = 0
* strength_index == 2 : enable_primary = 0, enable_secondary = 1
* strength_index == 3 : enable_primary = 0, enable_secondary = 0
*/
const cdef_filter_block_func cdef_filter_fn[
4] = {
cdef_filter_8_0, cdef_filter_8_1, cdef_filter_8_2, cdef_filter_8_3
};
for (bi =
0; bi < cdef_count; bi++) {
by = dlist[bi].by;
bx = dlist[bi].bx;
const int t =
(pli ? pri_strength : adjust_strength(pri_strength, var[by][bx]));
const int strength_index = (sec_strength ==
0) | ((t ==
0) <<
1);
cdef_filter_fn[strength_index](
&dst8[(by << bh_log2) * dstride + (bx << bw_log2)], dstride,
&in[(by * CDEF_BSTRIDE << bh_log2) + (bx << bw_log2)], t,
sec_strength, pri_strength ? dir[by][bx] :
0, damping, damping,
coeff_shift, block_width, block_height);
}
}
else {
const int block_width =
8 >> xdec;
const int block_height =
8 >> ydec;
/*
* strength_index == 0 : enable_primary = 1, enable_secondary = 1
* strength_index == 1 : enable_primary = 1, enable_secondary = 0
* strength_index == 2 : enable_primary = 0, enable_secondary = 1
* strength_index == 3 : enable_primary = 0, enable_secondary = 0
*/
const cdef_filter_block_func cdef_filter_fn[
4] = {
cdef_filter_16_0, cdef_filter_16_1, cdef_filter_16_2, cdef_filter_16_3
};
for (bi =
0; bi < cdef_count; bi++) {
by = dlist[bi].by;
bx = dlist[bi].bx;
const int t =
(pli ? pri_strength : adjust_strength(pri_strength, var[by][bx]));
const int strength_index = (sec_strength ==
0) | ((t ==
0) <<
1);
cdef_filter_fn[strength_index](
&dst16[dirinit ? bi << (bw_log2 + bh_log2)
: (by << bh_log2) * dstride + (bx << bw_log2)],
dirinit ?
1 << bw_log2 : dstride,
&in[(by * CDEF_BSTRIDE << bh_log2) + (bx << bw_log2)], t,
sec_strength, pri_strength ? dir[by][bx] :
0, damping, damping,
coeff_shift, block_width, block_height);
}
}
}
