1 /* 2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved 3 * 4 * This source code is subject to the terms of the BSD 2 Clause License and 5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License 6 * was not distributed with this source code in the LICENSE file, you can 7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open 8 * Media Patent License 1.0 was not distributed with this source code in the 9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent. 10 */ 11 #include <assert.h> 12 13 #include "av1/encoder/cost.h" 14 #include "av1/common/entropy.h" 15 16 // round(-log2(i/256.) * (1 << AV1_PROB_COST_SHIFT)); i = 128~255. 17 const uint16_t av1_prob_cost[128] = { 18 512, 506, 501, 495, 489, 484, 478, 473, 467, 462, 456, 451, 446, 441, 435, 19 430, 425, 420, 415, 410, 405, 400, 395, 390, 385, 380, 375, 371, 366, 361, 20 356, 352, 347, 343, 338, 333, 329, 324, 320, 316, 311, 307, 302, 298, 294, 21 289, 285, 281, 277, 273, 268, 264, 260, 256, 252, 248, 244, 240, 236, 232, 22 228, 224, 220, 216, 212, 209, 205, 201, 197, 194, 190, 186, 182, 179, 175, 23 171, 168, 164, 161, 157, 153, 150, 146, 143, 139, 136, 132, 129, 125, 122, 24 119, 115, 112, 109, 105, 102, 99, 95, 92, 89, 86, 82, 79, 76, 73, 25 70, 66, 63, 60, 57, 54, 51, 48, 45, 42, 38, 35, 32, 29, 26, 26 23, 20, 18, 15, 12, 9, 6, 3, 27 }; 28 29 void av1_cost_tokens_from_cdf(int *costs, const aom_cdf_prob *cdf, 30 const int *inv_map) { 31 int i; 32 aom_cdf_prob prev_cdf = 0; 33 for (i = 0;; ++i) { 34 aom_cdf_prob p15 = AOM_ICDF(cdf[i]) - prev_cdf; 35 p15 = (p15 < EC_MIN_PROB) ? EC_MIN_PROB : p15; 36 prev_cdf = AOM_ICDF(cdf[i]); 37 38 if (inv_map) 39 costs[inv_map[i]] = av1_cost_symbol(p15); 40 else 41 costs[i] = av1_cost_symbol(p15); 42 43 // Stop once we reach the end of the CDF 44 if (cdf[i] == AOM_ICDF(CDF_PROB_TOP)) break; 45 } 46 } 47