/* * 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> #ifdef HAVE_CONFIG_H #include "./config.h" #endif #include "./aom_dsp_rtcd.h" #include "./av1_rtcd.h" #include "./cdef.h" /* Generated from gen_filter_tables.c. */ const int OD_DIRECTION_OFFSETS_TABLE[8][3] = { { -1 * OD_FILT_BSTRIDE + 1, -2 * OD_FILT_BSTRIDE + 2, -3 * OD_FILT_BSTRIDE + 3 }, { 0 * OD_FILT_BSTRIDE + 1, -1 * OD_FILT_BSTRIDE + 2, -1 * OD_FILT_BSTRIDE + 3 }, { 0 * OD_FILT_BSTRIDE + 1, 0 * OD_FILT_BSTRIDE + 2, 0 * OD_FILT_BSTRIDE + 3 }, { 0 * OD_FILT_BSTRIDE + 1, 1 * OD_FILT_BSTRIDE + 2, 1 * OD_FILT_BSTRIDE + 3 }, { 1 * OD_FILT_BSTRIDE + 1, 2 * OD_FILT_BSTRIDE + 2, 3 * OD_FILT_BSTRIDE + 3 }, { 1 * OD_FILT_BSTRIDE + 0, 2 * OD_FILT_BSTRIDE + 1, 3 * OD_FILT_BSTRIDE + 1 }, { 1 * OD_FILT_BSTRIDE + 0, 2 * OD_FILT_BSTRIDE + 0, 3 * OD_FILT_BSTRIDE + 0 }, { 1 * OD_FILT_BSTRIDE + 0, 2 * OD_FILT_BSTRIDE - 1, 3 * OD_FILT_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 od_dir_find8_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; } /* Smooth in the direction detected. */ void od_filter_dering_direction_8x8_c(uint16_t *y, int ystride, const uint16_t *in, int threshold, int dir, int damping) { int i; int j; int k; static const int taps[3] = { 3, 2, 1 }; for (i = 0; i < 8; i++) { for (j = 0; j < 8; j++) { int16_t sum; int16_t xx; int16_t yy; xx = in[i * OD_FILT_BSTRIDE + j]; sum = 0; for (k = 0; k < 3; k++) { int16_t p0; int16_t p1; p0 = in[i * OD_FILT_BSTRIDE + j + OD_DIRECTION_OFFSETS_TABLE[dir][k]] - xx; p1 = in[i * OD_FILT_BSTRIDE + j - OD_DIRECTION_OFFSETS_TABLE[dir][k]] - xx; sum += taps[k] * constrain(p0, threshold, damping); sum += taps[k] * constrain(p1, threshold, damping); } sum = (sum + 8) >> 4; yy = xx + sum; y[i * ystride + j] = yy; } } } /* Smooth in the direction detected. */ void od_filter_dering_direction_4x4_c(uint16_t *y, int ystride, const uint16_t *in, int threshold, int dir, int damping) { int i; int j; int k; static const int taps[2] = { 4, 1 }; for (i = 0; i < 4; i++) { for (j = 0; j < 4; j++) { int16_t sum; int16_t xx; int16_t yy; xx = in[i * OD_FILT_BSTRIDE + j]; sum = 0; for (k = 0; k < 2; k++) { int16_t p0; int16_t p1; p0 = in[i * OD_FILT_BSTRIDE + j + OD_DIRECTION_OFFSETS_TABLE[dir][k]] - xx; p1 = in[i * OD_FILT_BSTRIDE + j - OD_DIRECTION_OFFSETS_TABLE[dir][k]] - xx; sum += taps[k] * constrain(p0, threshold, damping); sum += taps[k] * constrain(p1, threshold, damping); } sum = (sum + 8) >> 4; yy = xx + sum; y[i * ystride + j] = yy; } } } /* Compute deringing filter threshold 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 od_adjust_thresh(int threshold, 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 threshold. */ return var ? (threshold * (4 + i) + 8) >> 4 : 0; } void copy_8x8_16bit_to_16bit_c(uint16_t *dst, int dstride, const uint16_t *src, int sstride) { int i, j; for (i = 0; i < 8; i++) for (j = 0; j < 8; j++) dst[i * dstride + j] = src[i * sstride + j]; } void copy_4x4_16bit_to_16bit_c(uint16_t *dst, int dstride, const uint16_t *src, int sstride) { int i, j; for (i = 0; i < 4; i++) for (j = 0; j < 4; j++) dst[i * dstride + j] = src[i * sstride + j]; } void copy_dering_16bit_to_16bit(uint16_t *dst, int dstride, uint16_t *src, dering_list *dlist, int dering_count, int bsize) { int bi, bx, by; if (bsize == BLOCK_8X8) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_8x8_16bit_to_16bit(&dst[(by << 3) * dstride + (bx << 3)], dstride, &src[bi << (3 + 3)], 8); } } else if (bsize == BLOCK_4X8) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_16bit(&dst[(by << 3) * dstride + (bx << 2)], dstride, &src[bi << (3 + 2)], 4); copy_4x4_16bit_to_16bit(&dst[((by << 3) + 4) * dstride + (bx << 2)], dstride, &src[(bi << (3 + 2)) + 4 * 4], 4); } } else if (bsize == BLOCK_8X4) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_16bit(&dst[(by << 2) * dstride + (bx << 3)], dstride, &src[bi << (2 + 3)], 8); copy_4x4_16bit_to_16bit(&dst[(by << 2) * dstride + (bx << 3) + 4], dstride, &src[(bi << (2 + 3)) + 4], 8); } } else { assert(bsize == BLOCK_4X4); for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_16bit(&dst[(by << 2) * dstride + (bx << 2)], dstride, &src[bi << (2 + 2)], 4); } } } void copy_8x8_16bit_to_8bit_c(uint8_t *dst, int dstride, const uint16_t *src, int sstride) { int i, j; for (i = 0; i < 8; i++) for (j = 0; j < 8; j++) dst[i * dstride + j] = (uint8_t)src[i * sstride + j]; } void copy_4x4_16bit_to_8bit_c(uint8_t *dst, int dstride, const uint16_t *src, int sstride) { int i, j; for (i = 0; i < 4; i++) for (j = 0; j < 4; j++) dst[i * dstride + j] = (uint8_t)src[i * sstride + j]; } static void copy_dering_16bit_to_8bit(uint8_t *dst, int dstride, const uint16_t *src, dering_list *dlist, int dering_count, int bsize) { int bi, bx, by; if (bsize == BLOCK_8X8) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_8x8_16bit_to_8bit(&dst[(by << 3) * dstride + (bx << 3)], dstride, &src[bi << (3 + 3)], 8); } } else if (bsize == BLOCK_4X8) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_8bit(&dst[(by << 3) * dstride + (bx << 2)], dstride, &src[bi << (3 + 2)], 4); copy_4x4_16bit_to_8bit(&dst[((by << 3) + 4) * dstride + (bx << 2)], dstride, &src[(bi << (3 + 2)) + 4 * 4], 4); } } else if (bsize == BLOCK_8X4) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_8bit(&dst[(by << 2) * dstride + (bx << 3)], dstride, &src[bi << (2 + 3)], 8); copy_4x4_16bit_to_8bit(&dst[(by << 2) * dstride + (bx << 3) + 4], dstride, &src[(bi << (2 + 3)) + 4], 8); } } else { assert(bsize == BLOCK_4X4); for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; copy_4x4_16bit_to_8bit(&dst[(by << 2) * dstride + (bx << 2)], dstride, &src[bi << (2 * 2)], 4); } } } int get_filter_skip(int level) { int filter_skip = level & 1; if (level == 1) filter_skip = 0; return filter_skip; } void od_dering(uint8_t *dst, int dstride, uint16_t *y, uint16_t *in, int xdec, int ydec, int dir[OD_DERING_NBLOCKS][OD_DERING_NBLOCKS], int *dirinit, int var[OD_DERING_NBLOCKS][OD_DERING_NBLOCKS], int pli, dering_list *dlist, int dering_count, int level, int clpf_strength, int clpf_damping, int dering_damping, int coeff_shift, int skip_dering, int hbd) { int bi; int bx; int by; int bsize, bsizex, bsizey; int threshold = (level >> 1) << coeff_shift; int filter_skip = get_filter_skip(level); if (level == 1) threshold = 31 << coeff_shift; od_filter_dering_direction_func filter_dering_direction[] = { od_filter_dering_direction_4x4, od_filter_dering_direction_8x8 }; clpf_damping += coeff_shift - (pli != AOM_PLANE_Y); dering_damping += coeff_shift - (pli != AOM_PLANE_Y); bsize = ydec ? (xdec ? BLOCK_4X4 : BLOCK_8X4) : (xdec ? BLOCK_4X8 : BLOCK_8X8); bsizex = 3 - xdec; bsizey = 3 - ydec; if (!skip_dering) { if (pli == 0) { if (!dirinit || !*dirinit) { for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; dir[by][bx] = od_dir_find8(&in[8 * by * OD_FILT_BSTRIDE + 8 * bx], OD_FILT_BSTRIDE, &var[by][bx], coeff_shift); } if (dirinit) *dirinit = 1; } } // Only run dering for non-zero threshold (which is always the case for // 4:2:2 or 4:4:0). If we don't dering, we still need to eventually write // something out in y[] later. if (threshold != 0) { assert(bsize == BLOCK_8X8 || bsize == BLOCK_4X4); for (bi = 0; bi < dering_count; bi++) { int t = !filter_skip && dlist[bi].skip ? 0 : threshold; by = dlist[bi].by; bx = dlist[bi].bx; (filter_dering_direction[bsize == BLOCK_8X8])( &y[bi << (bsizex + bsizey)], 1 << bsizex, &in[(by * OD_FILT_BSTRIDE << bsizey) + (bx << bsizex)], pli ? t : od_adjust_thresh(t, var[by][bx]), dir[by][bx], dering_damping); } } } if (clpf_strength) { if (threshold && !skip_dering) copy_dering_16bit_to_16bit(in, OD_FILT_BSTRIDE, y, dlist, dering_count, bsize); for (bi = 0; bi < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; int py = by << bsizey; int px = bx << bsizex; if (!filter_skip && dlist[bi].skip) continue; if (!dst || hbd) { // 16 bit destination if high bitdepth or 8 bit destination not given (!threshold || (dir[by][bx] < 4 && dir[by][bx]) ? aom_clpf_block_hbd : aom_clpf_hblock_hbd)( dst ? (uint16_t *)dst + py * dstride + px : &y[bi << (bsizex + bsizey)], in + py * OD_FILT_BSTRIDE + px, dst && hbd ? dstride : 1 << bsizex, OD_FILT_BSTRIDE, 1 << bsizex, 1 << bsizey, clpf_strength << coeff_shift, clpf_damping); } else { // Do clpf and write the result to an 8 bit destination (!threshold || (dir[by][bx] < 4 && dir[by][bx]) ? aom_clpf_block : aom_clpf_hblock)( dst + py * dstride + px, in + py * OD_FILT_BSTRIDE + px, dstride, OD_FILT_BSTRIDE, 1 << bsizex, 1 << bsizey, clpf_strength << coeff_shift, clpf_damping); } } } else if (threshold != 0) { // No clpf, so copy instead if (hbd) { copy_dering_16bit_to_16bit((uint16_t *)dst, dstride, y, dlist, dering_count, bsize); } else { copy_dering_16bit_to_8bit(dst, dstride, y, dlist, dering_count, bsize); } } else if (dirinit) { // If we're here, both dering and clpf are off, 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 < dering_count; bi++) { by = dlist[bi].by; bx = dlist[bi].bx; int iy, ix; // TODO(stemidts/jmvalin): SIMD optimisations for (iy = 0; iy < 1 << bsizey; iy++) for (ix = 0; ix < 1 << bsizex; ix++) y[(bi << (bsizex + bsizey)) + (iy << bsizex) + ix] = in[((by << bsizey) + iy) * OD_FILT_BSTRIDE + (bx << bsizex) + ix]; } } }