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Diffstat (limited to 'ffmpeg/libavcodec/acelp_pitch_delay.h')
| -rw-r--r-- | ffmpeg/libavcodec/acelp_pitch_delay.h | 252 |
1 files changed, 0 insertions, 252 deletions
diff --git a/ffmpeg/libavcodec/acelp_pitch_delay.h b/ffmpeg/libavcodec/acelp_pitch_delay.h deleted file mode 100644 index 72977f1..0000000 --- a/ffmpeg/libavcodec/acelp_pitch_delay.h +++ /dev/null @@ -1,252 +0,0 @@ -/* - * gain code, gain pitch and pitch delay decoding - * - * Copyright (c) 2008 Vladimir Voroshilov - * - * This file is part of FFmpeg. - * - * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. - * - * FFmpeg is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with FFmpeg; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#ifndef AVCODEC_ACELP_PITCH_DELAY_H -#define AVCODEC_ACELP_PITCH_DELAY_H - -#include <stdint.h> -#include "dsputil.h" - -#define PITCH_DELAY_MIN 20 -#define PITCH_DELAY_MAX 143 - -/** - * @brief Decode pitch delay of the first subframe encoded by 8 bits with 1/3 - * resolution. - * @param ac_index adaptive codebook index (8 bits) - * - * @return pitch delay in 1/3 units - * - * Pitch delay is coded: - * with 1/3 resolution, 19 < pitch_delay < 85 - * integers only, 85 <= pitch_delay <= 143 - */ -int ff_acelp_decode_8bit_to_1st_delay3(int ac_index); - -/** - * @brief Decode pitch delay of the second subframe encoded by 5 or 6 bits - * with 1/3 precision. - * @param ac_index adaptive codebook index (5 or 6 bits) - * @param pitch_delay_min lower bound (integer) of pitch delay interval - * for second subframe - * - * @return pitch delay in 1/3 units - * - * Pitch delay is coded: - * with 1/3 resolution, -6 < pitch_delay - int(prev_pitch_delay) < 5 - * - * @remark The routine is used in G.729 @@8k, AMR @@10.2k, AMR @@7.95k, - * AMR @@7.4k for the second subframe. - */ -int ff_acelp_decode_5_6_bit_to_2nd_delay3( - int ac_index, - int pitch_delay_min); - -/** - * @brief Decode pitch delay with 1/3 precision. - * @param ac_index adaptive codebook index (4 bits) - * @param pitch_delay_min lower bound (integer) of pitch delay interval for - * second subframe - * - * @return pitch delay in 1/3 units - * - * Pitch delay is coded: - * integers only, -6 < pitch_delay - int(prev_pitch_delay) <= -2 - * with 1/3 resolution, -2 < pitch_delay - int(prev_pitch_delay) < 1 - * integers only, 1 <= pitch_delay - int(prev_pitch_delay) < 5 - * - * @remark The routine is used in G.729 @@6.4k, AMR @@6.7k, AMR @@5.9k, - * AMR @@5.15k, AMR @@4.75k for the second subframe. - */ -int ff_acelp_decode_4bit_to_2nd_delay3( - int ac_index, - int pitch_delay_min); - -/** - * @brief Decode pitch delay of the first subframe encoded by 9 bits - * with 1/6 precision. - * @param ac_index adaptive codebook index (9 bits) - * - * @return pitch delay in 1/6 units - * - * Pitch delay is coded: - * with 1/6 resolution, 17 < pitch_delay < 95 - * integers only, 95 <= pitch_delay <= 143 - * - * @remark The routine is used in AMR @@12.2k for the first and third subframes. - */ -int ff_acelp_decode_9bit_to_1st_delay6(int ac_index); - -/** - * @brief Decode pitch delay of the second subframe encoded by 6 bits - * with 1/6 precision. - * @param ac_index adaptive codebook index (6 bits) - * @param pitch_delay_min lower bound (integer) of pitch delay interval for - * second subframe - * - * @return pitch delay in 1/6 units - * - * Pitch delay is coded: - * with 1/6 resolution, -6 < pitch_delay - int(prev_pitch_delay) < 5 - * - * @remark The routine is used in AMR @@12.2k for the second and fourth subframes. - */ -int ff_acelp_decode_6bit_to_2nd_delay6( - int ac_index, - int pitch_delay_min); - -/** - * @brief Update past quantized energies - * @param[in,out] quant_energy past quantized energies (5.10) - * @param gain_corr_factor gain correction factor - * @param log2_ma_pred_order log2() of MA prediction order - * @param erasure frame erasure flag - * - * If frame erasure flag is not equal to zero, memory is updated with - * averaged energy, attenuated by 4dB: - * max(avg(quant_energy[i])-4, -14), i=0,ma_pred_order - * - * In normal mode memory is updated with - * Er - Ep = 20 * log10(gain_corr_factor) - * - * @remark The routine is used in G.729 and AMR (all modes). - */ -void ff_acelp_update_past_gain( - int16_t* quant_energy, - int gain_corr_factor, - int log2_ma_pred_order, - int erasure); - -/** - * @brief Decode the adaptive codebook gain and add - * correction (4.1.5 and 3.9.1 of G.729). - * @param dsp initialized dsputil context - * @param gain_corr_factor gain correction factor (2.13) - * @param fc_v fixed-codebook vector (2.13) - * @param mr_energy mean innovation energy and fixed-point correction (7.13) - * @param[in,out] quant_energy past quantized energies (5.10) - * @param subframe_size length of subframe - * - * @return quantized fixed-codebook gain (14.1) - * - * The routine implements equations 69, 66 and 71 of the G.729 specification (3.9.1) - * - * Em - mean innovation energy (dB, constant, depends on decoding algorithm) - * Ep - mean-removed predicted energy (dB) - * Er - mean-removed innovation energy (dB) - * Ei - mean energy of the fixed-codebook contribution (dB) - * N - subframe_size - * M - MA (Moving Average) prediction order - * gc - fixed-codebook gain - * gc_p - predicted fixed-codebook gain - * - * Fixed codebook gain is computed using predicted gain gc_p and - * correction factor gain_corr_factor as shown below: - * - * gc = gc_p * gain_corr_factor - * - * The predicted fixed codebook gain gc_p is found by predicting - * the energy of the fixed-codebook contribution from the energy - * of previous fixed-codebook contributions. - * - * mean = 1/N * sum(i,0,N){ fc_v[i] * fc_v[i] } - * - * Ei = 10log(mean) - * - * Er = 10log(1/N * gc^2 * mean) - Em = 20log(gc) + Ei - Em - * - * Replacing Er with Ep and gc with gc_p we will receive: - * - * Ep = 10log(1/N * gc_p^2 * mean) - Em = 20log(gc_p) + Ei - Em - * - * and from above: - * - * gc_p = 10^((Ep - Ei + Em) / 20) - * - * Ep is predicted using past energies and prediction coefficients: - * - * Ep = sum(i,0,M){ ma_prediction_coeff[i] * quant_energy[i] } - * - * gc_p in fixed-point arithmetic is calculated as following: - * - * mean = 1/N * sum(i,0,N){ (fc_v[i] / 2^13) * (fc_v[i] / 2^13) } = - * = 1/N * sum(i,0,N) { fc_v[i] * fc_v[i] } / 2^26 - * - * Ei = 10log(mean) = -10log(N) - 10log(2^26) + - * + 10log(sum(i,0,N) { fc_v[i] * fc_v[i] }) - * - * Ep - Ei + Em = Ep + Em + 10log(N) + 10log(2^26) - - * - 10log(sum(i,0,N) { fc_v[i] * fc_v[i] }) = - * = Ep + mr_energy - 10log(sum(i,0,N) { fc_v[i] * fc_v[i] }) - * - * gc_p = 10 ^ ((Ep - Ei + Em) / 20) = - * = 2 ^ (3.3219 * (Ep - Ei + Em) / 20) = 2 ^ (0.166 * (Ep - Ei + Em)) - * - * where - * - * mr_energy = Em + 10log(N) + 10log(2^26) - * - * @remark The routine is used in G.729 and AMR (all modes). - */ -int16_t ff_acelp_decode_gain_code( - DSPContext *dsp, - int gain_corr_factor, - const int16_t* fc_v, - int mr_energy, - const int16_t* quant_energy, - const int16_t* ma_prediction_coeff, - int subframe_size, - int max_pred_order); - -/** - * Calculate fixed gain (part of section 6.1.3 of AMR spec) - * - * @param fixed_gain_factor gain correction factor - * @param fixed_mean_energy mean decoded algebraic codebook vector energy - * @param prediction_error vector of the quantified predictor errors of - * the four previous subframes. It is updated by this function. - * @param energy_mean desired mean innovation energy - * @param pred_table table of four moving average coefficients - */ -float ff_amr_set_fixed_gain(float fixed_gain_factor, float fixed_mean_energy, - float *prediction_error, float energy_mean, - const float *pred_table); - - -/** - * Decode the adaptive codebook index to the integer and fractional parts - * of the pitch lag for one subframe at 1/3 fractional precision. - * - * The choice of pitch lag is described in 3GPP TS 26.090 section 5.6.1. - * - * @param lag_int integer part of pitch lag of the current subframe - * @param lag_frac fractional part of pitch lag of the current subframe - * @param pitch_index parsed adaptive codebook (pitch) index - * @param prev_lag_int integer part of pitch lag for the previous subframe - * @param subframe current subframe number - * @param third_as_first treat the third frame the same way as the first - */ -void ff_decode_pitch_lag(int *lag_int, int *lag_frac, int pitch_index, - const int prev_lag_int, const int subframe, - int third_as_first, int resolution); - -#endif /* AVCODEC_ACELP_PITCH_DELAY_H */ |