| /* |
| * 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 "av1/encoder/cost.h" |
| #include "av1/encoder/palette.h" |
| #include "av1/encoder/random.h" |
| |
| #define AV1_K_MEANS_DIM 1 |
| #include "av1/encoder/k_means_template.h" |
| #undef AV1_K_MEANS_DIM |
| #define AV1_K_MEANS_DIM 2 |
| #include "av1/encoder/k_means_template.h" |
| #undef AV1_K_MEANS_DIM |
| |
| static int int_comparer(const void *a, const void *b) { |
| return (*(int *)a - *(int *)b); |
| } |
| |
| int av1_remove_duplicates(int *centroids, int num_centroids) { |
| int num_unique; // number of unique centroids |
| int i; |
| qsort(centroids, num_centroids, sizeof(*centroids), int_comparer); |
| // Remove duplicates. |
| num_unique = 1; |
| for (i = 1; i < num_centroids; ++i) { |
| if (centroids[i] != centroids[i - 1]) { // found a new unique centroid |
| centroids[num_unique++] = centroids[i]; |
| } |
| } |
| return num_unique; |
| } |
| |
| static int delta_encode_cost(const int *colors, int num, int bit_depth, |
| int min_val) { |
| if (num <= 0) return 0; |
| int bits_cost = bit_depth; |
| if (num == 1) return bits_cost; |
| bits_cost += 2; |
| int max_delta = 0; |
| int deltas[PALETTE_MAX_SIZE]; |
| const int min_bits = bit_depth - 3; |
| for (int i = 1; i < num; ++i) { |
| const int delta = colors[i] - colors[i - 1]; |
| deltas[i - 1] = delta; |
| assert(delta >= min_val); |
| if (delta > max_delta) max_delta = delta; |
| } |
| int bits_per_delta = AOMMAX(av1_ceil_log2(max_delta + 1 - min_val), min_bits); |
| assert(bits_per_delta <= bit_depth); |
| int range = (1 << bit_depth) - colors[0] - min_val; |
| for (int i = 0; i < num - 1; ++i) { |
| bits_cost += bits_per_delta; |
| range -= deltas[i]; |
| bits_per_delta = AOMMIN(bits_per_delta, av1_ceil_log2(range)); |
| } |
| return bits_cost; |
| } |
| |
| int av1_index_color_cache(const uint16_t *color_cache, int n_cache, |
| const uint16_t *colors, int n_colors, |
| uint8_t *cache_color_found, int *out_cache_colors) { |
| if (n_cache <= 0) { |
| for (int i = 0; i < n_colors; ++i) out_cache_colors[i] = colors[i]; |
| return n_colors; |
| } |
| memset(cache_color_found, 0, n_cache * sizeof(*cache_color_found)); |
| int n_in_cache = 0; |
| int in_cache_flags[PALETTE_MAX_SIZE]; |
| memset(in_cache_flags, 0, sizeof(in_cache_flags)); |
| for (int i = 0; i < n_cache && n_in_cache < n_colors; ++i) { |
| for (int j = 0; j < n_colors; ++j) { |
| if (colors[j] == color_cache[i]) { |
| in_cache_flags[j] = 1; |
| cache_color_found[i] = 1; |
| ++n_in_cache; |
| break; |
| } |
| } |
| } |
| int j = 0; |
| for (int i = 0; i < n_colors; ++i) |
| if (!in_cache_flags[i]) out_cache_colors[j++] = colors[i]; |
| assert(j == n_colors - n_in_cache); |
| return j; |
| } |
| |
| int av1_get_palette_delta_bits_v(const PALETTE_MODE_INFO *const pmi, |
| int bit_depth, int *zero_count, |
| int *min_bits) { |
| const int n = pmi->palette_size[1]; |
| const int max_val = 1 << bit_depth; |
| int max_d = 0; |
| *min_bits = bit_depth - 4; |
| *zero_count = 0; |
| for (int i = 1; i < n; ++i) { |
| const int delta = pmi->palette_colors[2 * PALETTE_MAX_SIZE + i] - |
| pmi->palette_colors[2 * PALETTE_MAX_SIZE + i - 1]; |
| const int v = abs(delta); |
| const int d = AOMMIN(v, max_val - v); |
| if (d > max_d) max_d = d; |
| if (d == 0) ++(*zero_count); |
| } |
| return AOMMAX(av1_ceil_log2(max_d + 1), *min_bits); |
| } |
| |
| int av1_palette_color_cost_y(const PALETTE_MODE_INFO *const pmi, |
| uint16_t *color_cache, int n_cache, |
| int bit_depth) { |
| const int n = pmi->palette_size[0]; |
| int out_cache_colors[PALETTE_MAX_SIZE]; |
| uint8_t cache_color_found[2 * PALETTE_MAX_SIZE]; |
| const int n_out_cache = |
| av1_index_color_cache(color_cache, n_cache, pmi->palette_colors, n, |
| cache_color_found, out_cache_colors); |
| const int total_bits = |
| n_cache + delta_encode_cost(out_cache_colors, n_out_cache, bit_depth, 1); |
| return av1_cost_literal(total_bits); |
| } |
| |
| int av1_palette_color_cost_uv(const PALETTE_MODE_INFO *const pmi, |
| uint16_t *color_cache, int n_cache, |
| int bit_depth) { |
| const int n = pmi->palette_size[1]; |
| int total_bits = 0; |
| // U channel palette color cost. |
| int out_cache_colors[PALETTE_MAX_SIZE]; |
| uint8_t cache_color_found[2 * PALETTE_MAX_SIZE]; |
| const int n_out_cache = av1_index_color_cache( |
| color_cache, n_cache, pmi->palette_colors + PALETTE_MAX_SIZE, n, |
| cache_color_found, out_cache_colors); |
| total_bits += |
| n_cache + delta_encode_cost(out_cache_colors, n_out_cache, bit_depth, 0); |
| |
| // V channel palette color cost. |
| int zero_count = 0, min_bits_v = 0; |
| const int bits_v = |
| av1_get_palette_delta_bits_v(pmi, bit_depth, &zero_count, &min_bits_v); |
| const int bits_using_delta = |
| 2 + bit_depth + (bits_v + 1) * (n - 1) - zero_count; |
| const int bits_using_raw = bit_depth * n; |
| total_bits += 1 + AOMMIN(bits_using_delta, bits_using_raw); |
| return av1_cost_literal(total_bits); |
| } |