yading@10: /*
yading@10:  * G.729, G729 Annex D decoders
yading@10:  * Copyright (c) 2008 Vladimir Voroshilov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include <inttypes.h>
yading@10: #include <string.h>
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "libavutil/avutil.h"
yading@10: #include "get_bits.h"
yading@10: #include "dsputil.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: 
yading@10: #include "g729.h"
yading@10: #include "lsp.h"
yading@10: #include "celp_math.h"
yading@10: #include "celp_filters.h"
yading@10: #include "acelp_filters.h"
yading@10: #include "acelp_pitch_delay.h"
yading@10: #include "acelp_vectors.h"
yading@10: #include "g729data.h"
yading@10: #include "g729postfilter.h"
yading@10: 
yading@10: /**
yading@10:  * minimum quantized LSF value (3.2.4)
yading@10:  * 0.005 in Q13
yading@10:  */
yading@10: #define LSFQ_MIN                   40
yading@10: 
yading@10: /**
yading@10:  * maximum quantized LSF value (3.2.4)
yading@10:  * 3.135 in Q13
yading@10:  */
yading@10: #define LSFQ_MAX                   25681
yading@10: 
yading@10: /**
yading@10:  * minimum LSF distance (3.2.4)
yading@10:  * 0.0391 in Q13
yading@10:  */
yading@10: #define LSFQ_DIFF_MIN              321
yading@10: 
yading@10: /// interpolation filter length
yading@10: #define INTERPOL_LEN              11
yading@10: 
yading@10: /**
yading@10:  * minimum gain pitch value (3.8, Equation 47)
yading@10:  * 0.2 in (1.14)
yading@10:  */
yading@10: #define SHARP_MIN                  3277
yading@10: 
yading@10: /**
yading@10:  * maximum gain pitch value (3.8, Equation 47)
yading@10:  * (EE) This does not comply with the specification.
yading@10:  * Specification says about 0.8, which should be
yading@10:  * 13107 in (1.14), but reference C code uses
yading@10:  * 13017 (equals to 0.7945) instead of it.
yading@10:  */
yading@10: #define SHARP_MAX                  13017
yading@10: 
yading@10: /**
yading@10:  * MR_ENERGY (mean removed energy) = mean_energy + 10 * log10(2^26  * subframe_size) in (7.13)
yading@10:  */
yading@10: #define MR_ENERGY 1018156
yading@10: 
yading@10: #define DECISION_NOISE        0
yading@10: #define DECISION_INTERMEDIATE 1
yading@10: #define DECISION_VOICE        2
yading@10: 
yading@10: typedef enum {
yading@10:     FORMAT_G729_8K = 0,
yading@10:     FORMAT_G729D_6K4,
yading@10:     FORMAT_COUNT,
yading@10: } G729Formats;
yading@10: 
yading@10: typedef struct {
yading@10:     uint8_t ac_index_bits[2];   ///< adaptive codebook index for second subframe (size in bits)
yading@10:     uint8_t parity_bit;         ///< parity bit for pitch delay
yading@10:     uint8_t gc_1st_index_bits;  ///< gain codebook (first stage) index (size in bits)
yading@10:     uint8_t gc_2nd_index_bits;  ///< gain codebook (second stage) index (size in bits)
yading@10:     uint8_t fc_signs_bits;      ///< number of pulses in fixed-codebook vector
yading@10:     uint8_t fc_indexes_bits;    ///< size (in bits) of fixed-codebook index entry
yading@10: } G729FormatDescription;
yading@10: 
yading@10: typedef struct {
yading@10:     DSPContext dsp;
yading@10: 
yading@10:     /// past excitation signal buffer
yading@10:     int16_t exc_base[2*SUBFRAME_SIZE+PITCH_DELAY_MAX+INTERPOL_LEN];
yading@10: 
yading@10:     int16_t* exc;               ///< start of past excitation data in buffer
yading@10:     int pitch_delay_int_prev;   ///< integer part of previous subframe's pitch delay (4.1.3)
yading@10: 
yading@10:     /// (2.13) LSP quantizer outputs
yading@10:     int16_t  past_quantizer_output_buf[MA_NP + 1][10];
yading@10:     int16_t* past_quantizer_outputs[MA_NP + 1];
yading@10: 
yading@10:     int16_t lsfq[10];           ///< (2.13) quantized LSF coefficients from previous frame
yading@10:     int16_t lsp_buf[2][10];     ///< (0.15) LSP coefficients (previous and current frames) (3.2.5)
yading@10:     int16_t *lsp[2];            ///< pointers to lsp_buf
yading@10: 
yading@10:     int16_t quant_energy[4];    ///< (5.10) past quantized energy
yading@10: 
yading@10:     /// previous speech data for LP synthesis filter
yading@10:     int16_t syn_filter_data[10];
yading@10: 
yading@10: 
yading@10:     /// residual signal buffer (used in long-term postfilter)
yading@10:     int16_t residual[SUBFRAME_SIZE + RES_PREV_DATA_SIZE];
yading@10: 
yading@10:     /// previous speech data for residual calculation filter
yading@10:     int16_t res_filter_data[SUBFRAME_SIZE+10];
yading@10: 
yading@10:     /// previous speech data for short-term postfilter
yading@10:     int16_t pos_filter_data[SUBFRAME_SIZE+10];
yading@10: 
yading@10:     /// (1.14) pitch gain of current and five previous subframes
yading@10:     int16_t past_gain_pitch[6];
yading@10: 
yading@10:     /// (14.1) gain code from current and previous subframe
yading@10:     int16_t past_gain_code[2];
yading@10: 
yading@10:     /// voice decision on previous subframe (0-noise, 1-intermediate, 2-voice), G.729D
yading@10:     int16_t voice_decision;
yading@10: 
yading@10:     int16_t onset;              ///< detected onset level (0-2)
yading@10:     int16_t was_periodic;       ///< whether previous frame was declared as periodic or not (4.4)
yading@10:     int16_t ht_prev_data;       ///< previous data for 4.2.3, equation 86
yading@10:     int gain_coeff;             ///< (1.14) gain coefficient (4.2.4)
yading@10:     uint16_t rand_value;        ///< random number generator value (4.4.4)
yading@10:     int ma_predictor_prev;      ///< switched MA predictor of LSP quantizer from last good frame
yading@10: 
yading@10:     /// (14.14) high-pass filter data (past input)
yading@10:     int hpf_f[2];
yading@10: 
yading@10:     /// high-pass filter data (past output)
yading@10:     int16_t hpf_z[2];
yading@10: }  G729Context;
yading@10: 
yading@10: static const G729FormatDescription format_g729_8k = {
yading@10:     .ac_index_bits     = {8,5},
yading@10:     .parity_bit        = 1,
yading@10:     .gc_1st_index_bits = GC_1ST_IDX_BITS_8K,
yading@10:     .gc_2nd_index_bits = GC_2ND_IDX_BITS_8K,
yading@10:     .fc_signs_bits     = 4,
yading@10:     .fc_indexes_bits   = 13,
yading@10: };
yading@10: 
yading@10: static const G729FormatDescription format_g729d_6k4 = {
yading@10:     .ac_index_bits     = {8,4},
yading@10:     .parity_bit        = 0,
yading@10:     .gc_1st_index_bits = GC_1ST_IDX_BITS_6K4,
yading@10:     .gc_2nd_index_bits = GC_2ND_IDX_BITS_6K4,
yading@10:     .fc_signs_bits     = 2,
yading@10:     .fc_indexes_bits   = 9,
yading@10: };
yading@10: 
yading@10: /**
yading@10:  * @brief pseudo random number generator
yading@10:  */
yading@10: static inline uint16_t g729_prng(uint16_t value)
yading@10: {
yading@10:     return 31821 * value + 13849;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Get parity bit of bit 2..7
yading@10:  */
yading@10: static inline int get_parity(uint8_t value)
yading@10: {
yading@10:    return (0x6996966996696996ULL >> (value >> 2)) & 1;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decodes LSF (Line Spectral Frequencies) from L0-L3 (3.2.4).
yading@10:  * @param[out] lsfq (2.13) quantized LSF coefficients
yading@10:  * @param[in,out] past_quantizer_outputs (2.13) quantizer outputs from previous frames
yading@10:  * @param ma_predictor switched MA predictor of LSP quantizer
yading@10:  * @param vq_1st first stage vector of quantizer
yading@10:  * @param vq_2nd_low second stage lower vector of LSP quantizer
yading@10:  * @param vq_2nd_high second stage higher vector of LSP quantizer
yading@10:  */
yading@10: static void lsf_decode(int16_t* lsfq, int16_t* past_quantizer_outputs[MA_NP + 1],
yading@10:                        int16_t ma_predictor,
yading@10:                        int16_t vq_1st, int16_t vq_2nd_low, int16_t vq_2nd_high)
yading@10: {
yading@10:     int i,j;
yading@10:     static const uint8_t min_distance[2]={10, 5}; //(2.13)
yading@10:     int16_t* quantizer_output = past_quantizer_outputs[MA_NP];
yading@10: 
yading@10:     for (i = 0; i < 5; i++) {
yading@10:         quantizer_output[i]     = cb_lsp_1st[vq_1st][i    ] + cb_lsp_2nd[vq_2nd_low ][i    ];
yading@10:         quantizer_output[i + 5] = cb_lsp_1st[vq_1st][i + 5] + cb_lsp_2nd[vq_2nd_high][i + 5];
yading@10:     }
yading@10: 
yading@10:     for (j = 0; j < 2; j++) {
yading@10:         for (i = 1; i < 10; i++) {
yading@10:             int diff = (quantizer_output[i - 1] - quantizer_output[i] + min_distance[j]) >> 1;
yading@10:             if (diff > 0) {
yading@10:                 quantizer_output[i - 1] -= diff;
yading@10:                 quantizer_output[i    ] += diff;
yading@10:             }
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     for (i = 0; i < 10; i++) {
yading@10:         int sum = quantizer_output[i] * cb_ma_predictor_sum[ma_predictor][i];
yading@10:         for (j = 0; j < MA_NP; j++)
yading@10:             sum += past_quantizer_outputs[j][i] * cb_ma_predictor[ma_predictor][j][i];
yading@10: 
yading@10:         lsfq[i] = sum >> 15;
yading@10:     }
yading@10: 
yading@10:     ff_acelp_reorder_lsf(lsfq, LSFQ_DIFF_MIN, LSFQ_MIN, LSFQ_MAX, 10);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Restores past LSP quantizer output using LSF from previous frame
yading@10:  * @param[in,out] lsfq (2.13) quantized LSF coefficients
yading@10:  * @param[in,out] past_quantizer_outputs (2.13) quantizer outputs from previous frames
yading@10:  * @param ma_predictor_prev MA predictor from previous frame
yading@10:  * @param lsfq_prev (2.13) quantized LSF coefficients from previous frame
yading@10:  */
yading@10: static void lsf_restore_from_previous(int16_t* lsfq,
yading@10:                                       int16_t* past_quantizer_outputs[MA_NP + 1],
yading@10:                                       int ma_predictor_prev)
yading@10: {
yading@10:     int16_t* quantizer_output = past_quantizer_outputs[MA_NP];
yading@10:     int i,k;
yading@10: 
yading@10:     for (i = 0; i < 10; i++) {
yading@10:         int tmp = lsfq[i] << 15;
yading@10: 
yading@10:         for (k = 0; k < MA_NP; k++)
yading@10:             tmp -= past_quantizer_outputs[k][i] * cb_ma_predictor[ma_predictor_prev][k][i];
yading@10: 
yading@10:         quantizer_output[i] = ((tmp >> 15) * cb_ma_predictor_sum_inv[ma_predictor_prev][i]) >> 12;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Constructs new excitation signal and applies phase filter to it
yading@10:  * @param[out] out constructed speech signal
yading@10:  * @param in original excitation signal
yading@10:  * @param fc_cur (2.13) original fixed-codebook vector
yading@10:  * @param gain_code (14.1) gain code
yading@10:  * @param subframe_size length of the subframe
yading@10:  */
yading@10: static void g729d_get_new_exc(
yading@10:         int16_t* out,
yading@10:         const int16_t* in,
yading@10:         const int16_t* fc_cur,
yading@10:         int dstate,
yading@10:         int gain_code,
yading@10:         int subframe_size)
yading@10: {
yading@10:     int i;
yading@10:     int16_t fc_new[SUBFRAME_SIZE];
yading@10: 
yading@10:     ff_celp_convolve_circ(fc_new, fc_cur, phase_filter[dstate], subframe_size);
yading@10: 
yading@10:     for(i=0; i<subframe_size; i++)
yading@10:     {
yading@10:         out[i]  = in[i];
yading@10:         out[i] -= (gain_code * fc_cur[i] + 0x2000) >> 14;
yading@10:         out[i] += (gain_code * fc_new[i] + 0x2000) >> 14;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Makes decision about onset in current subframe
yading@10:  * @param past_onset decision result of previous subframe
yading@10:  * @param past_gain_code gain code of current and previous subframe
yading@10:  *
yading@10:  * @return onset decision result for current subframe
yading@10:  */
yading@10: static int g729d_onset_decision(int past_onset, const int16_t* past_gain_code)
yading@10: {
yading@10:     if((past_gain_code[0] >> 1) > past_gain_code[1])
yading@10:         return 2;
yading@10:     else
yading@10:         return FFMAX(past_onset-1, 0);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Makes decision about voice presence in current subframe
yading@10:  * @param onset onset level
yading@10:  * @param prev_voice_decision voice decision result from previous subframe
yading@10:  * @param past_gain_pitch pitch gain of current and previous subframes
yading@10:  *
yading@10:  * @return voice decision result for current subframe
yading@10:  */
yading@10: static int16_t g729d_voice_decision(int onset, int prev_voice_decision, const int16_t* past_gain_pitch)
yading@10: {
yading@10:     int i, low_gain_pitch_cnt, voice_decision;
yading@10: 
yading@10:     if(past_gain_pitch[0] >= 14745)      // 0.9
yading@10:         voice_decision = DECISION_VOICE;
yading@10:     else if (past_gain_pitch[0] <= 9830) // 0.6
yading@10:         voice_decision = DECISION_NOISE;
yading@10:     else
yading@10:         voice_decision = DECISION_INTERMEDIATE;
yading@10: 
yading@10:     for(i=0, low_gain_pitch_cnt=0; i<6; i++)
yading@10:         if(past_gain_pitch[i] < 9830)
yading@10:             low_gain_pitch_cnt++;
yading@10: 
yading@10:     if(low_gain_pitch_cnt > 2 && !onset)
yading@10:         voice_decision = DECISION_NOISE;
yading@10: 
yading@10:     if(!onset && voice_decision > prev_voice_decision + 1)
yading@10:         voice_decision--;
yading@10: 
yading@10:     if(onset && voice_decision < DECISION_VOICE)
yading@10:         voice_decision++;
yading@10: 
yading@10:     return voice_decision;
yading@10: }
yading@10: 
yading@10: static int32_t scalarproduct_int16_c(const int16_t * v1, const int16_t * v2, int order)
yading@10: {
yading@10:     int res = 0;
yading@10: 
yading@10:     while (order--)
yading@10:         res += *v1++ * *v2++;
yading@10: 
yading@10:     return res;
yading@10: }
yading@10: 
yading@10: static av_cold int decoder_init(AVCodecContext * avctx)
yading@10: {
yading@10:     G729Context* ctx = avctx->priv_data;
yading@10:     int i,k;
yading@10: 
yading@10:     if (avctx->channels != 1) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Only mono sound is supported (requested channels: %d).\n", avctx->channels);
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10:     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
yading@10: 
yading@10:     /* Both 8kbit/s and 6.4kbit/s modes uses two subframes per frame. */
yading@10:     avctx->frame_size = SUBFRAME_SIZE << 1;
yading@10: 
yading@10:     ctx->gain_coeff = 16384; // 1.0 in (1.14)
yading@10: 
yading@10:     for (k = 0; k < MA_NP + 1; k++) {
yading@10:         ctx->past_quantizer_outputs[k] = ctx->past_quantizer_output_buf[k];
yading@10:         for (i = 1; i < 11; i++)
yading@10:             ctx->past_quantizer_outputs[k][i - 1] = (18717 * i) >> 3;
yading@10:     }
yading@10: 
yading@10:     ctx->lsp[0] = ctx->lsp_buf[0];
yading@10:     ctx->lsp[1] = ctx->lsp_buf[1];
yading@10:     memcpy(ctx->lsp[0], lsp_init, 10 * sizeof(int16_t));
yading@10: 
yading@10:     ctx->exc = &ctx->exc_base[PITCH_DELAY_MAX+INTERPOL_LEN];
yading@10: 
yading@10:     ctx->pitch_delay_int_prev = PITCH_DELAY_MIN;
yading@10: 
yading@10:     /* random seed initialization */
yading@10:     ctx->rand_value = 21845;
yading@10: 
yading@10:     /* quantized prediction error */
yading@10:     for(i=0; i<4; i++)
yading@10:         ctx->quant_energy[i] = -14336; // -14 in (5.10)
yading@10: 
yading@10:     ff_dsputil_init(&ctx->dsp, avctx);
yading@10:     ctx->dsp.scalarproduct_int16 = scalarproduct_int16_c;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
yading@10:                         AVPacket *avpkt)
yading@10: {
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size       = avpkt->size;
yading@10:     int16_t *out_frame;
yading@10:     GetBitContext gb;
yading@10:     const G729FormatDescription *format;
yading@10:     int frame_erasure = 0;    ///< frame erasure detected during decoding
yading@10:     int bad_pitch = 0;        ///< parity check failed
yading@10:     int i;
yading@10:     int16_t *tmp;
yading@10:     G729Formats packet_type;
yading@10:     G729Context *ctx = avctx->priv_data;
yading@10:     int16_t lp[2][11];           // (3.12)
yading@10:     uint8_t ma_predictor;     ///< switched MA predictor of LSP quantizer
yading@10:     uint8_t quantizer_1st;    ///< first stage vector of quantizer
yading@10:     uint8_t quantizer_2nd_lo; ///< second stage lower vector of quantizer (size in bits)
yading@10:     uint8_t quantizer_2nd_hi; ///< second stage higher vector of quantizer (size in bits)
yading@10: 
yading@10:     int pitch_delay_int[2];      // pitch delay, integer part
yading@10:     int pitch_delay_3x;          // pitch delay, multiplied by 3
yading@10:     int16_t fc[SUBFRAME_SIZE];   // fixed-codebook vector
yading@10:     int16_t synth[SUBFRAME_SIZE+10]; // fixed-codebook vector
yading@10:     int j, ret;
yading@10:     int gain_before, gain_after;
yading@10:     int is_periodic = 0;         // whether one of the subframes is declared as periodic or not
yading@10:     AVFrame *frame = data;
yading@10: 
yading@10:     frame->nb_samples = SUBFRAME_SIZE<<1;
yading@10:     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
yading@10:         return ret;
yading@10:     out_frame = (int16_t*) frame->data[0];
yading@10: 
yading@10:     if (buf_size == 10) {
yading@10:         packet_type = FORMAT_G729_8K;
yading@10:         format = &format_g729_8k;
yading@10:         //Reset voice decision
yading@10:         ctx->onset = 0;
yading@10:         ctx->voice_decision = DECISION_VOICE;
yading@10:         av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729 @ 8kbit/s");
yading@10:     } else if (buf_size == 8) {
yading@10:         packet_type = FORMAT_G729D_6K4;
yading@10:         format = &format_g729d_6k4;
yading@10:         av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729D @ 6.4kbit/s");
yading@10:     } else {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Packet size %d is unknown.\n", buf_size);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     for (i=0; i < buf_size; i++)
yading@10:         frame_erasure |= buf[i];
yading@10:     frame_erasure = !frame_erasure;
yading@10: 
yading@10:     init_get_bits(&gb, buf, 8*buf_size);
yading@10: 
yading@10:     ma_predictor     = get_bits(&gb, 1);
yading@10:     quantizer_1st    = get_bits(&gb, VQ_1ST_BITS);
yading@10:     quantizer_2nd_lo = get_bits(&gb, VQ_2ND_BITS);
yading@10:     quantizer_2nd_hi = get_bits(&gb, VQ_2ND_BITS);
yading@10: 
yading@10:     if(frame_erasure)
yading@10:         lsf_restore_from_previous(ctx->lsfq, ctx->past_quantizer_outputs,
yading@10:                                   ctx->ma_predictor_prev);
yading@10:     else {
yading@10:         lsf_decode(ctx->lsfq, ctx->past_quantizer_outputs,
yading@10:                    ma_predictor,
yading@10:                    quantizer_1st, quantizer_2nd_lo, quantizer_2nd_hi);
yading@10:         ctx->ma_predictor_prev = ma_predictor;
yading@10:     }
yading@10: 
yading@10:     tmp = ctx->past_quantizer_outputs[MA_NP];
yading@10:     memmove(ctx->past_quantizer_outputs + 1, ctx->past_quantizer_outputs,
yading@10:             MA_NP * sizeof(int16_t*));
yading@10:     ctx->past_quantizer_outputs[0] = tmp;
yading@10: 
yading@10:     ff_acelp_lsf2lsp(ctx->lsp[1], ctx->lsfq, 10);
yading@10: 
yading@10:     ff_acelp_lp_decode(&lp[0][0], &lp[1][0], ctx->lsp[1], ctx->lsp[0], 10);
yading@10: 
yading@10:     FFSWAP(int16_t*, ctx->lsp[1], ctx->lsp[0]);
yading@10: 
yading@10:     for (i = 0; i < 2; i++) {
yading@10:         int gain_corr_factor;
yading@10: 
yading@10:         uint8_t ac_index;      ///< adaptive codebook index
yading@10:         uint8_t pulses_signs;  ///< fixed-codebook vector pulse signs
yading@10:         int fc_indexes;        ///< fixed-codebook indexes
yading@10:         uint8_t gc_1st_index;  ///< gain codebook (first stage) index
yading@10:         uint8_t gc_2nd_index;  ///< gain codebook (second stage) index
yading@10: 
yading@10:         ac_index      = get_bits(&gb, format->ac_index_bits[i]);
yading@10:         if(!i && format->parity_bit)
yading@10:             bad_pitch = get_parity(ac_index) == get_bits1(&gb);
yading@10:         fc_indexes    = get_bits(&gb, format->fc_indexes_bits);
yading@10:         pulses_signs  = get_bits(&gb, format->fc_signs_bits);
yading@10:         gc_1st_index  = get_bits(&gb, format->gc_1st_index_bits);
yading@10:         gc_2nd_index  = get_bits(&gb, format->gc_2nd_index_bits);
yading@10: 
yading@10:         if (frame_erasure)
yading@10:             pitch_delay_3x   = 3 * ctx->pitch_delay_int_prev;
yading@10:         else if(!i) {
yading@10:             if (bad_pitch)
yading@10:                 pitch_delay_3x   = 3 * ctx->pitch_delay_int_prev;
yading@10:             else
yading@10:                 pitch_delay_3x = ff_acelp_decode_8bit_to_1st_delay3(ac_index);
yading@10:         } else {
yading@10:             int pitch_delay_min = av_clip(ctx->pitch_delay_int_prev - 5,
yading@10:                                           PITCH_DELAY_MIN, PITCH_DELAY_MAX - 9);
yading@10: 
yading@10:             if(packet_type == FORMAT_G729D_6K4)
yading@10:                 pitch_delay_3x = ff_acelp_decode_4bit_to_2nd_delay3(ac_index, pitch_delay_min);
yading@10:             else
yading@10:                 pitch_delay_3x = ff_acelp_decode_5_6_bit_to_2nd_delay3(ac_index, pitch_delay_min);
yading@10:         }
yading@10: 
yading@10:         /* Round pitch delay to nearest (used everywhere except ff_acelp_interpolate). */
yading@10:         pitch_delay_int[i]  = (pitch_delay_3x + 1) / 3;
yading@10:         if (pitch_delay_int[i] > PITCH_DELAY_MAX) {
yading@10:             av_log(avctx, AV_LOG_WARNING, "pitch_delay_int %d is too large\n", pitch_delay_int[i]);
yading@10:             pitch_delay_int[i] = PITCH_DELAY_MAX;
yading@10:         }
yading@10: 
yading@10:         if (frame_erasure) {
yading@10:             ctx->rand_value = g729_prng(ctx->rand_value);
yading@10:             fc_indexes   = ctx->rand_value & ((1 << format->fc_indexes_bits) - 1);
yading@10: 
yading@10:             ctx->rand_value = g729_prng(ctx->rand_value);
yading@10:             pulses_signs = ctx->rand_value;
yading@10:         }
yading@10: 
yading@10: 
yading@10:         memset(fc, 0, sizeof(int16_t) * SUBFRAME_SIZE);
yading@10:         switch (packet_type) {
yading@10:             case FORMAT_G729_8K:
yading@10:                 ff_acelp_fc_pulse_per_track(fc, ff_fc_4pulses_8bits_tracks_13,
yading@10:                                             ff_fc_4pulses_8bits_track_4,
yading@10:                                             fc_indexes, pulses_signs, 3, 3);
yading@10:                 break;
yading@10:             case FORMAT_G729D_6K4:
yading@10:                 ff_acelp_fc_pulse_per_track(fc, ff_fc_2pulses_9bits_track1_gray,
yading@10:                                             ff_fc_2pulses_9bits_track2_gray,
yading@10:                                             fc_indexes, pulses_signs, 1, 4);
yading@10:                 break;
yading@10:         }
yading@10: 
yading@10:         /*
yading@10:           This filter enhances harmonic components of the fixed-codebook vector to
yading@10:           improve the quality of the reconstructed speech.
yading@10: 
yading@10:                      / fc_v[i],                                    i < pitch_delay
yading@10:           fc_v[i] = <
yading@10:                      \ fc_v[i] + gain_pitch * fc_v[i-pitch_delay], i >= pitch_delay
yading@10:         */
yading@10:         ff_acelp_weighted_vector_sum(fc + pitch_delay_int[i],
yading@10:                                      fc + pitch_delay_int[i],
yading@10:                                      fc, 1 << 14,
yading@10:                                      av_clip(ctx->past_gain_pitch[0], SHARP_MIN, SHARP_MAX),
yading@10:                                      0, 14,
yading@10:                                      SUBFRAME_SIZE - pitch_delay_int[i]);
yading@10: 
yading@10:         memmove(ctx->past_gain_pitch+1, ctx->past_gain_pitch, 5 * sizeof(int16_t));
yading@10:         ctx->past_gain_code[1] = ctx->past_gain_code[0];
yading@10: 
yading@10:         if (frame_erasure) {
yading@10:             ctx->past_gain_pitch[0] = (29491 * ctx->past_gain_pitch[0]) >> 15; // 0.90 (0.15)
yading@10:             ctx->past_gain_code[0]  = ( 2007 * ctx->past_gain_code[0] ) >> 11; // 0.98 (0.11)
yading@10: 
yading@10:             gain_corr_factor = 0;
yading@10:         } else {
yading@10:             if (packet_type == FORMAT_G729D_6K4) {
yading@10:                 ctx->past_gain_pitch[0]  = cb_gain_1st_6k4[gc_1st_index][0] +
yading@10:                                            cb_gain_2nd_6k4[gc_2nd_index][0];
yading@10:                 gain_corr_factor = cb_gain_1st_6k4[gc_1st_index][1] +
yading@10:                                    cb_gain_2nd_6k4[gc_2nd_index][1];
yading@10: 
yading@10:                 /* Without check below overflow can occur in ff_acelp_update_past_gain.
yading@10:                    It is not issue for G.729, because gain_corr_factor in it's case is always
yading@10:                    greater than 1024, while in G.729D it can be even zero. */
yading@10:                 gain_corr_factor = FFMAX(gain_corr_factor, 1024);
yading@10: #ifndef G729_BITEXACT
yading@10:                 gain_corr_factor >>= 1;
yading@10: #endif
yading@10:             } else {
yading@10:                 ctx->past_gain_pitch[0]  = cb_gain_1st_8k[gc_1st_index][0] +
yading@10:                                            cb_gain_2nd_8k[gc_2nd_index][0];
yading@10:                 gain_corr_factor = cb_gain_1st_8k[gc_1st_index][1] +
yading@10:                                    cb_gain_2nd_8k[gc_2nd_index][1];
yading@10:             }
yading@10: 
yading@10:             /* Decode the fixed-codebook gain. */
yading@10:             ctx->past_gain_code[0] = ff_acelp_decode_gain_code(&ctx->dsp, gain_corr_factor,
yading@10:                                                                fc, MR_ENERGY,
yading@10:                                                                ctx->quant_energy,
yading@10:                                                                ma_prediction_coeff,
yading@10:                                                                SUBFRAME_SIZE, 4);
yading@10: #ifdef G729_BITEXACT
yading@10:             /*
yading@10:               This correction required to get bit-exact result with
yading@10:               reference code, because gain_corr_factor in G.729D is
yading@10:               two times larger than in original G.729.
yading@10: 
yading@10:               If bit-exact result is not issue then gain_corr_factor
yading@10:               can be simpler divided by 2 before call to g729_get_gain_code
yading@10:               instead of using correction below.
yading@10:             */
yading@10:             if (packet_type == FORMAT_G729D_6K4) {
yading@10:                 gain_corr_factor >>= 1;
yading@10:                 ctx->past_gain_code[0] >>= 1;
yading@10:             }
yading@10: #endif
yading@10:         }
yading@10:         ff_acelp_update_past_gain(ctx->quant_energy, gain_corr_factor, 2, frame_erasure);
yading@10: 
yading@10:         /* Routine requires rounding to lowest. */
yading@10:         ff_acelp_interpolate(ctx->exc + i * SUBFRAME_SIZE,
yading@10:                              ctx->exc + i * SUBFRAME_SIZE - pitch_delay_3x / 3,
yading@10:                              ff_acelp_interp_filter, 6,
yading@10:                              (pitch_delay_3x % 3) << 1,
yading@10:                              10, SUBFRAME_SIZE);
yading@10: 
yading@10:         ff_acelp_weighted_vector_sum(ctx->exc + i * SUBFRAME_SIZE,
yading@10:                                      ctx->exc + i * SUBFRAME_SIZE, fc,
yading@10:                                      (!ctx->was_periodic && frame_erasure) ? 0 : ctx->past_gain_pitch[0],
yading@10:                                      ( ctx->was_periodic && frame_erasure) ? 0 : ctx->past_gain_code[0],
yading@10:                                      1 << 13, 14, SUBFRAME_SIZE);
yading@10: 
yading@10:         memcpy(synth, ctx->syn_filter_data, 10 * sizeof(int16_t));
yading@10: 
yading@10:         if (ff_celp_lp_synthesis_filter(
yading@10:             synth+10,
yading@10:             &lp[i][1],
yading@10:             ctx->exc  + i * SUBFRAME_SIZE,
yading@10:             SUBFRAME_SIZE,
yading@10:             10,
yading@10:             1,
yading@10:             0,
yading@10:             0x800))
yading@10:             /* Overflow occurred, downscale excitation signal... */
yading@10:             for (j = 0; j < 2 * SUBFRAME_SIZE + PITCH_DELAY_MAX + INTERPOL_LEN; j++)
yading@10:                 ctx->exc_base[j] >>= 2;
yading@10: 
yading@10:         /* ... and make synthesis again. */
yading@10:         if (packet_type == FORMAT_G729D_6K4) {
yading@10:             int16_t exc_new[SUBFRAME_SIZE];
yading@10: 
yading@10:             ctx->onset = g729d_onset_decision(ctx->onset, ctx->past_gain_code);
yading@10:             ctx->voice_decision = g729d_voice_decision(ctx->onset, ctx->voice_decision, ctx->past_gain_pitch);
yading@10: 
yading@10:             g729d_get_new_exc(exc_new, ctx->exc  + i * SUBFRAME_SIZE, fc, ctx->voice_decision, ctx->past_gain_code[0], SUBFRAME_SIZE);
yading@10: 
yading@10:             ff_celp_lp_synthesis_filter(
yading@10:                     synth+10,
yading@10:                     &lp[i][1],
yading@10:                     exc_new,
yading@10:                     SUBFRAME_SIZE,
yading@10:                     10,
yading@10:                     0,
yading@10:                     0,
yading@10:                     0x800);
yading@10:         } else {
yading@10:             ff_celp_lp_synthesis_filter(
yading@10:                     synth+10,
yading@10:                     &lp[i][1],
yading@10:                     ctx->exc  + i * SUBFRAME_SIZE,
yading@10:                     SUBFRAME_SIZE,
yading@10:                     10,
yading@10:                     0,
yading@10:                     0,
yading@10:                     0x800);
yading@10:         }
yading@10:         /* Save data (without postfilter) for use in next subframe. */
yading@10:         memcpy(ctx->syn_filter_data, synth+SUBFRAME_SIZE, 10 * sizeof(int16_t));
yading@10: 
yading@10:         /* Calculate gain of unfiltered signal for use in AGC. */
yading@10:         gain_before = 0;
yading@10:         for (j = 0; j < SUBFRAME_SIZE; j++)
yading@10:             gain_before += FFABS(synth[j+10]);
yading@10: 
yading@10:         /* Call postfilter and also update voicing decision for use in next frame. */
yading@10:         ff_g729_postfilter(
yading@10:                 &ctx->dsp,
yading@10:                 &ctx->ht_prev_data,
yading@10:                 &is_periodic,
yading@10:                 &lp[i][0],
yading@10:                 pitch_delay_int[0],
yading@10:                 ctx->residual,
yading@10:                 ctx->res_filter_data,
yading@10:                 ctx->pos_filter_data,
yading@10:                 synth+10,
yading@10:                 SUBFRAME_SIZE);
yading@10: 
yading@10:         /* Calculate gain of filtered signal for use in AGC. */
yading@10:         gain_after = 0;
yading@10:         for(j=0; j<SUBFRAME_SIZE; j++)
yading@10:             gain_after += FFABS(synth[j+10]);
yading@10: 
yading@10:         ctx->gain_coeff = ff_g729_adaptive_gain_control(
yading@10:                 gain_before,
yading@10:                 gain_after,
yading@10:                 synth+10,
yading@10:                 SUBFRAME_SIZE,
yading@10:                 ctx->gain_coeff);
yading@10: 
yading@10:         if (frame_erasure)
yading@10:             ctx->pitch_delay_int_prev = FFMIN(ctx->pitch_delay_int_prev + 1, PITCH_DELAY_MAX);
yading@10:         else
yading@10:             ctx->pitch_delay_int_prev = pitch_delay_int[i];
yading@10: 
yading@10:         memcpy(synth+8, ctx->hpf_z, 2*sizeof(int16_t));
yading@10:         ff_acelp_high_pass_filter(
yading@10:                 out_frame + i*SUBFRAME_SIZE,
yading@10:                 ctx->hpf_f,
yading@10:                 synth+10,
yading@10:                 SUBFRAME_SIZE);
yading@10:         memcpy(ctx->hpf_z, synth+8+SUBFRAME_SIZE, 2*sizeof(int16_t));
yading@10:     }
yading@10: 
yading@10:     ctx->was_periodic = is_periodic;
yading@10: 
yading@10:     /* Save signal for use in next frame. */
yading@10:     memmove(ctx->exc_base, ctx->exc_base + 2 * SUBFRAME_SIZE, (PITCH_DELAY_MAX+INTERPOL_LEN)*sizeof(int16_t));
yading@10: 
yading@10:     *got_frame_ptr = 1;
yading@10:     return buf_size;
yading@10: }
yading@10: 
yading@10: AVCodec ff_g729_decoder = {
yading@10:     .name           = "g729",
yading@10:     .type           = AVMEDIA_TYPE_AUDIO,
yading@10:     .id             = AV_CODEC_ID_G729,
yading@10:     .priv_data_size = sizeof(G729Context),
yading@10:     .init           = decoder_init,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("G.729"),
yading@10: };