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Diffstat (limited to 'third_party/aom/av1/encoder/generic_encoder.c')
| -rw-r--r-- | third_party/aom/av1/encoder/generic_encoder.c | 157 |
1 files changed, 0 insertions, 157 deletions
diff --git a/third_party/aom/av1/encoder/generic_encoder.c b/third_party/aom/av1/encoder/generic_encoder.c deleted file mode 100644 index a31bb9ef6..000000000 --- a/third_party/aom/av1/encoder/generic_encoder.c +++ /dev/null @@ -1,157 +0,0 @@ -/* - * Copyright (c) 2001-2016, 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. - */ - -/* clang-format off */ - -#ifdef HAVE_CONFIG_H -# include "config.h" -#endif - -#include <stdio.h> - -#include "aom_dsp/bitwriter.h" -#include "av1/common/generic_code.h" -#include "av1/common/odintrin.h" -#include "pvq_encoder.h" - -/** Encodes a value from 0 to N-1 (with N up to 16) based on a cdf and adapts - * the cdf accordingly. - * - * @param [in,out] w multi-symbol entropy encoder - * @param [in] val variable being encoded - * @param [in,out] cdf CDF of the variable (Q15) - * @param [in] n number of values possible - * @param [in,out] count number of symbols encoded with that cdf so far - * @param [in] rate adaptation rate shift (smaller is faster) - */ -void aom_encode_cdf_adapt_q15(aom_writer *w, int val, uint16_t *cdf, int n, - int *count, int rate) { - int i; - if (*count == 0) { - /* On the first call, we normalize the cdf to (32768 - n). This should - eventually be moved to the state init, but for now it makes it much - easier to experiment and convert symbols to the Q15 adaptation.*/ - int ft; - ft = cdf[n - 1]; - for (i = 0; i < n; i++) { - cdf[i] = AOM_ICDF(cdf[i]*32768/ft); - } - } - aom_write_cdf(w, val, cdf, n); - aom_cdf_adapt_q15(val, cdf, n, count, rate); -} - -/** Encodes a random variable using a "generic" model, assuming that the - * distribution is one-sided (zero and up), has a single mode, and decays - * exponentially past the model. - * - * @param [in,out] w multi-symbol entropy encoder - * @param [in,out] model generic probability model - * @param [in] x variable being encoded - * @param [in,out] ExQ16 expectation of x (adapted) - * @param [in] integration integration period of ExQ16 (leaky average over - * 1<<integration samples) - */ -void generic_encode(aom_writer *w, generic_encoder *model, int x, - int *ex_q16, int integration) { - int lg_q1; - int shift; - int id; - uint16_t *cdf; - int xs; - lg_q1 = log_ex(*ex_q16); - OD_LOG((OD_LOG_ENTROPY_CODER, OD_LOG_DEBUG, - "%d %d", *ex_q16, lg_q1)); - /* If expectation is too large, shift x to ensure that - all we have past xs=15 is the exponentially decaying tail - of the distribution */ - shift = OD_MAXI(0, (lg_q1 - 5) >> 1); - /* Choose the cdf to use: we have two per "octave" of ExQ16 */ - id = OD_MINI(GENERIC_TABLES - 1, lg_q1); - cdf = model->cdf[id]; - xs = (x + (1 << shift >> 1)) >> shift; - aom_write_symbol_pvq(w, OD_MINI(15, xs), cdf, 16); - if (xs >= 15) { - int e; - unsigned decay; - /* Estimate decay based on the assumption that the distribution is close - to Laplacian for large values. We should probably have an adaptive - estimate instead. Note: The 2* is a kludge that's not fully understood - yet. */ - OD_ASSERT(*ex_q16 < INT_MAX >> 1); - e = ((2**ex_q16 >> 8) + (1 << shift >> 1)) >> shift; - decay = OD_MAXI(2, OD_MINI(254, 256*e/(e + 256))); - /* Encode the tail of the distribution assuming exponential decay. */ - aom_laplace_encode_special(w, xs - 15, decay); - } - if (shift != 0) { - int special; - /* Because of the rounding, there's only half the number of possibilities - for xs=0. */ - special = xs == 0; - if (shift - special > 0) { - aom_write_literal(w, x - (xs << shift) + (!special << (shift - 1)), - shift - special); - } - } - generic_model_update(ex_q16, x, integration); - OD_LOG((OD_LOG_ENTROPY_CODER, OD_LOG_DEBUG, - "enc: %d %d %d %d %d %x", *ex_q16, x, shift, id, xs, enc->rng)); -} - -/** Estimates the cost of encoding a value with generic_encode(). - * - * @param [in,out] model generic probability model - * @param [in] x variable being encoded - * @param [in,out] ExQ16 expectation of x (adapted) - * @return number of bits (approximation) - */ -double generic_encode_cost(generic_encoder *model, int x, int *ex_q16) { - int lg_q1; - int shift; - int id; - uint16_t *cdf; - int xs; - int extra; - lg_q1 = log_ex(*ex_q16); - /* If expectation is too large, shift x to ensure that - all we have past xs=15 is the exponentially decaying tail - of the distribution */ - shift = OD_MAXI(0, (lg_q1 - 5) >> 1); - /* Choose the cdf to use: we have two per "octave" of ExQ16 */ - id = OD_MINI(GENERIC_TABLES - 1, lg_q1); - cdf = model->cdf[id]; - xs = (x + (1 << shift >> 1)) >> shift; - extra = 0; - if (shift) extra = shift - (xs == 0); - xs = OD_MINI(15, xs); - /* Shortcut: assume it's going to cost 2 bits for the Laplace coder. */ - if (xs == 15) extra += 2; - return - extra - OD_LOG2((double)(cdf[xs] - (xs == 0 ? 0 : cdf[xs - 1]))/cdf[15]); -} - -/*Estimates the cost of encoding a value with a given CDF.*/ -double od_encode_cdf_cost(int val, uint16_t *cdf, int n) { - int total_prob; - int prev_prob; - double val_prob; - OD_ASSERT(n > 0); - total_prob = cdf[n - 1]; - if (val == 0) { - prev_prob = 0; - } - else { - prev_prob = cdf[val - 1]; - } - val_prob = (cdf[val] - prev_prob) / (double)total_prob; - return -OD_LOG2(val_prob); -} |