|  | /* | 
|  | * Copyright (c) 2021, Alliance for Open Media. All rights reserved | 
|  | * | 
|  | * This source code is subject to the terms of the BSD 3-Clause Clear License | 
|  | * and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear | 
|  | * License was not distributed with this source code in the LICENSE file, you | 
|  | * can obtain it at aomedia.org/license/software-license/bsd-3-c-c/.  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 | 
|  | * aomedia.org/license/patent-license/. | 
|  | */ | 
|  |  | 
|  | #include <math.h> | 
|  | #include <stdlib.h> | 
|  |  | 
|  | #include "config/aom_dsp_rtcd.h" | 
|  | #include "config/av1_rtcd.h" | 
|  |  | 
|  | #include "av1/common/cdef.h" | 
|  |  | 
|  | /* Generated from gen_filter_tables.c. */ | 
|  | DECLARE_ALIGNED(16, const int, cdef_directions[8][2]) = { | 
|  | { -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 } | 
|  | }; | 
|  |  | 
|  | /* 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; | 
|  | } | 
|  |  | 
|  | const int cdef_pri_taps[2][2] = { { 4, 2 }, { 3, 3 } }; | 
|  | const int cdef_sec_taps[2] = { 2, 1 }; | 
|  |  | 
|  | /* Smooth in the direction detected. */ | 
|  | void cdef_filter_block_c(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, | 
|  | BLOCK_SIZE bsize, int coeff_shift) { | 
|  | 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 < 4 << (bsize == BLOCK_8X8 || bsize == BLOCK_4X8); i++) { | 
|  | for (j = 0; j < 4 << (bsize == BLOCK_8X8 || bsize == BLOCK_8X4); 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++) { | 
|  | 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 (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); | 
|  | int16_t s0 = in[i * s + j + cdef_directions[(dir + 2) & 7][k]]; | 
|  | int16_t s1 = in[i * s + j - cdef_directions[(dir + 2) & 7][k]]; | 
|  | int16_t s2 = in[i * s + j + cdef_directions[(dir + 6) & 7][k]]; | 
|  | int16_t s3 = in[i * s + j - cdef_directions[(dir + 6) & 7][k]]; | 
|  | 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 = clamp((int16_t)x + ((8 + sum - (sum < 0)) >> 4), min, max); | 
|  | if (dst8) | 
|  | dst8[i * dstride + j] = (uint8_t)y; | 
|  | else | 
|  | dst16[i * dstride + j] = (uint16_t)y; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* 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; | 
|  | } | 
|  |  | 
|  | void av1_cdef_filter_fb(uint8_t *dst8, uint16_t *dst16, int dstride, | 
|  | 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) { | 
|  | for (bi = 0; bi < cdef_count; bi++) { | 
|  | by = dlist[bi].by; | 
|  | bx = dlist[bi].bx; | 
|  | dir[by][bx] = cdef_find_dir(&in[8 * by * CDEF_BSTRIDE + 8 * bx], | 
|  | CDEF_BSTRIDE, &var[by][bx], coeff_shift); | 
|  | } | 
|  | 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]]; | 
|  | } | 
|  | } | 
|  |  | 
|  | const BLOCK_SIZE bsize = | 
|  | ydec ? (xdec ? BLOCK_4X4 : BLOCK_8X4) : (xdec ? BLOCK_4X8 : BLOCK_8X8); | 
|  | const int t = pri_strength; | 
|  | const int s = sec_strength; | 
|  | for (bi = 0; bi < cdef_count; bi++) { | 
|  | by = dlist[bi].by; | 
|  | bx = dlist[bi].bx; | 
|  | if (dst8) { | 
|  | cdef_filter_block( | 
|  | &dst8[(by << bh_log2) * dstride + (bx << bw_log2)], NULL, dstride, | 
|  | &in[(by * CDEF_BSTRIDE << bh_log2) + (bx << bw_log2)], | 
|  | (pli ? t : adjust_strength(t, var[by][bx])), s, t ? dir[by][bx] : 0, | 
|  | damping, damping, bsize, coeff_shift); | 
|  | } else { | 
|  | cdef_filter_block( | 
|  | NULL, | 
|  | &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)], | 
|  | (pli ? t : adjust_strength(t, var[by][bx])), s, t ? dir[by][bx] : 0, | 
|  | damping, damping, bsize, coeff_shift); | 
|  | } | 
|  | } | 
|  | } |