summaryrefslogtreecommitdiffstats
path: root/libavcodec/g729dec.c
diff options
context:
space:
mode:
Diffstat (limited to 'libavcodec/g729dec.c')
-rw-r--r--libavcodec/g729dec.c718
1 files changed, 718 insertions, 0 deletions
diff --git a/libavcodec/g729dec.c b/libavcodec/g729dec.c
new file mode 100644
index 0000000..2e1bf18
--- /dev/null
+++ b/libavcodec/g729dec.c
@@ -0,0 +1,718 @@
+/*
+ * G.729, G729 Annex D decoders
+ * 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
+ */
+
+#include <inttypes.h>
+#include <string.h>
+
+#include "avcodec.h"
+#include "libavutil/avutil.h"
+#include "get_bits.h"
+#include "audiodsp.h"
+#include "internal.h"
+
+
+#include "g729.h"
+#include "lsp.h"
+#include "celp_math.h"
+#include "celp_filters.h"
+#include "acelp_filters.h"
+#include "acelp_pitch_delay.h"
+#include "acelp_vectors.h"
+#include "g729data.h"
+#include "g729postfilter.h"
+
+/**
+ * minimum quantized LSF value (3.2.4)
+ * 0.005 in Q13
+ */
+#define LSFQ_MIN 40
+
+/**
+ * maximum quantized LSF value (3.2.4)
+ * 3.135 in Q13
+ */
+#define LSFQ_MAX 25681
+
+/**
+ * minimum LSF distance (3.2.4)
+ * 0.0391 in Q13
+ */
+#define LSFQ_DIFF_MIN 321
+
+/// interpolation filter length
+#define INTERPOL_LEN 11
+
+/**
+ * minimum gain pitch value (3.8, Equation 47)
+ * 0.2 in (1.14)
+ */
+#define SHARP_MIN 3277
+
+/**
+ * maximum gain pitch value (3.8, Equation 47)
+ * (EE) This does not comply with the specification.
+ * Specification says about 0.8, which should be
+ * 13107 in (1.14), but reference C code uses
+ * 13017 (equals to 0.7945) instead of it.
+ */
+#define SHARP_MAX 13017
+
+/**
+ * MR_ENERGY (mean removed energy) = mean_energy + 10 * log10(2^26 * subframe_size) in (7.13)
+ */
+#define MR_ENERGY 1018156
+
+#define DECISION_NOISE 0
+#define DECISION_INTERMEDIATE 1
+#define DECISION_VOICE 2
+
+typedef enum {
+ FORMAT_G729_8K = 0,
+ FORMAT_G729D_6K4,
+ FORMAT_COUNT,
+} G729Formats;
+
+typedef struct {
+ uint8_t ac_index_bits[2]; ///< adaptive codebook index for second subframe (size in bits)
+ uint8_t parity_bit; ///< parity bit for pitch delay
+ uint8_t gc_1st_index_bits; ///< gain codebook (first stage) index (size in bits)
+ uint8_t gc_2nd_index_bits; ///< gain codebook (second stage) index (size in bits)
+ uint8_t fc_signs_bits; ///< number of pulses in fixed-codebook vector
+ uint8_t fc_indexes_bits; ///< size (in bits) of fixed-codebook index entry
+} G729FormatDescription;
+
+typedef struct {
+ AudioDSPContext adsp;
+
+ /// past excitation signal buffer
+ int16_t exc_base[2*SUBFRAME_SIZE+PITCH_DELAY_MAX+INTERPOL_LEN];
+
+ int16_t* exc; ///< start of past excitation data in buffer
+ int pitch_delay_int_prev; ///< integer part of previous subframe's pitch delay (4.1.3)
+
+ /// (2.13) LSP quantizer outputs
+ int16_t past_quantizer_output_buf[MA_NP + 1][10];
+ int16_t* past_quantizer_outputs[MA_NP + 1];
+
+ int16_t lsfq[10]; ///< (2.13) quantized LSF coefficients from previous frame
+ int16_t lsp_buf[2][10]; ///< (0.15) LSP coefficients (previous and current frames) (3.2.5)
+ int16_t *lsp[2]; ///< pointers to lsp_buf
+
+ int16_t quant_energy[4]; ///< (5.10) past quantized energy
+
+ /// previous speech data for LP synthesis filter
+ int16_t syn_filter_data[10];
+
+
+ /// residual signal buffer (used in long-term postfilter)
+ int16_t residual[SUBFRAME_SIZE + RES_PREV_DATA_SIZE];
+
+ /// previous speech data for residual calculation filter
+ int16_t res_filter_data[SUBFRAME_SIZE+10];
+
+ /// previous speech data for short-term postfilter
+ int16_t pos_filter_data[SUBFRAME_SIZE+10];
+
+ /// (1.14) pitch gain of current and five previous subframes
+ int16_t past_gain_pitch[6];
+
+ /// (14.1) gain code from current and previous subframe
+ int16_t past_gain_code[2];
+
+ /// voice decision on previous subframe (0-noise, 1-intermediate, 2-voice), G.729D
+ int16_t voice_decision;
+
+ int16_t onset; ///< detected onset level (0-2)
+ int16_t was_periodic; ///< whether previous frame was declared as periodic or not (4.4)
+ int16_t ht_prev_data; ///< previous data for 4.2.3, equation 86
+ int gain_coeff; ///< (1.14) gain coefficient (4.2.4)
+ uint16_t rand_value; ///< random number generator value (4.4.4)
+ int ma_predictor_prev; ///< switched MA predictor of LSP quantizer from last good frame
+
+ /// (14.14) high-pass filter data (past input)
+ int hpf_f[2];
+
+ /// high-pass filter data (past output)
+ int16_t hpf_z[2];
+} G729Context;
+
+static const G729FormatDescription format_g729_8k = {
+ .ac_index_bits = {8,5},
+ .parity_bit = 1,
+ .gc_1st_index_bits = GC_1ST_IDX_BITS_8K,
+ .gc_2nd_index_bits = GC_2ND_IDX_BITS_8K,
+ .fc_signs_bits = 4,
+ .fc_indexes_bits = 13,
+};
+
+static const G729FormatDescription format_g729d_6k4 = {
+ .ac_index_bits = {8,4},
+ .parity_bit = 0,
+ .gc_1st_index_bits = GC_1ST_IDX_BITS_6K4,
+ .gc_2nd_index_bits = GC_2ND_IDX_BITS_6K4,
+ .fc_signs_bits = 2,
+ .fc_indexes_bits = 9,
+};
+
+/**
+ * @brief pseudo random number generator
+ */
+static inline uint16_t g729_prng(uint16_t value)
+{
+ return 31821 * value + 13849;
+}
+
+/**
+ * Decodes LSF (Line Spectral Frequencies) from L0-L3 (3.2.4).
+ * @param[out] lsfq (2.13) quantized LSF coefficients
+ * @param[in,out] past_quantizer_outputs (2.13) quantizer outputs from previous frames
+ * @param ma_predictor switched MA predictor of LSP quantizer
+ * @param vq_1st first stage vector of quantizer
+ * @param vq_2nd_low second stage lower vector of LSP quantizer
+ * @param vq_2nd_high second stage higher vector of LSP quantizer
+ */
+static void lsf_decode(int16_t* lsfq, int16_t* past_quantizer_outputs[MA_NP + 1],
+ int16_t ma_predictor,
+ int16_t vq_1st, int16_t vq_2nd_low, int16_t vq_2nd_high)
+{
+ int i,j;
+ static const uint8_t min_distance[2]={10, 5}; //(2.13)
+ int16_t* quantizer_output = past_quantizer_outputs[MA_NP];
+
+ for (i = 0; i < 5; i++) {
+ quantizer_output[i] = cb_lsp_1st[vq_1st][i ] + cb_lsp_2nd[vq_2nd_low ][i ];
+ quantizer_output[i + 5] = cb_lsp_1st[vq_1st][i + 5] + cb_lsp_2nd[vq_2nd_high][i + 5];
+ }
+
+ for (j = 0; j < 2; j++) {
+ for (i = 1; i < 10; i++) {
+ int diff = (quantizer_output[i - 1] - quantizer_output[i] + min_distance[j]) >> 1;
+ if (diff > 0) {
+ quantizer_output[i - 1] -= diff;
+ quantizer_output[i ] += diff;
+ }
+ }
+ }
+
+ for (i = 0; i < 10; i++) {
+ int sum = quantizer_output[i] * cb_ma_predictor_sum[ma_predictor][i];
+ for (j = 0; j < MA_NP; j++)
+ sum += past_quantizer_outputs[j][i] * cb_ma_predictor[ma_predictor][j][i];
+
+ lsfq[i] = sum >> 15;
+ }
+
+ ff_acelp_reorder_lsf(lsfq, LSFQ_DIFF_MIN, LSFQ_MIN, LSFQ_MAX, 10);
+}
+
+/**
+ * Restores past LSP quantizer output using LSF from previous frame
+ * @param[in,out] lsfq (2.13) quantized LSF coefficients
+ * @param[in,out] past_quantizer_outputs (2.13) quantizer outputs from previous frames
+ * @param ma_predictor_prev MA predictor from previous frame
+ * @param lsfq_prev (2.13) quantized LSF coefficients from previous frame
+ */
+static void lsf_restore_from_previous(int16_t* lsfq,
+ int16_t* past_quantizer_outputs[MA_NP + 1],
+ int ma_predictor_prev)
+{
+ int16_t* quantizer_output = past_quantizer_outputs[MA_NP];
+ int i,k;
+
+ for (i = 0; i < 10; i++) {
+ int tmp = lsfq[i] << 15;
+
+ for (k = 0; k < MA_NP; k++)
+ tmp -= past_quantizer_outputs[k][i] * cb_ma_predictor[ma_predictor_prev][k][i];
+
+ quantizer_output[i] = ((tmp >> 15) * cb_ma_predictor_sum_inv[ma_predictor_prev][i]) >> 12;
+ }
+}
+
+/**
+ * Constructs new excitation signal and applies phase filter to it
+ * @param[out] out constructed speech signal
+ * @param in original excitation signal
+ * @param fc_cur (2.13) original fixed-codebook vector
+ * @param gain_code (14.1) gain code
+ * @param subframe_size length of the subframe
+ */
+static void g729d_get_new_exc(
+ int16_t* out,
+ const int16_t* in,
+ const int16_t* fc_cur,
+ int dstate,
+ int gain_code,
+ int subframe_size)
+{
+ int i;
+ int16_t fc_new[SUBFRAME_SIZE];
+
+ ff_celp_convolve_circ(fc_new, fc_cur, phase_filter[dstate], subframe_size);
+
+ for(i=0; i<subframe_size; i++)
+ {
+ out[i] = in[i];
+ out[i] -= (gain_code * fc_cur[i] + 0x2000) >> 14;
+ out[i] += (gain_code * fc_new[i] + 0x2000) >> 14;
+ }
+}
+
+/**
+ * Makes decision about onset in current subframe
+ * @param past_onset decision result of previous subframe
+ * @param past_gain_code gain code of current and previous subframe
+ *
+ * @return onset decision result for current subframe
+ */
+static int g729d_onset_decision(int past_onset, const int16_t* past_gain_code)
+{
+ if((past_gain_code[0] >> 1) > past_gain_code[1])
+ return 2;
+ else
+ return FFMAX(past_onset-1, 0);
+}
+
+/**
+ * Makes decision about voice presence in current subframe
+ * @param onset onset level
+ * @param prev_voice_decision voice decision result from previous subframe
+ * @param past_gain_pitch pitch gain of current and previous subframes
+ *
+ * @return voice decision result for current subframe
+ */
+static int16_t g729d_voice_decision(int onset, int prev_voice_decision, const int16_t* past_gain_pitch)
+{
+ int i, low_gain_pitch_cnt, voice_decision;
+
+ if(past_gain_pitch[0] >= 14745) // 0.9
+ voice_decision = DECISION_VOICE;
+ else if (past_gain_pitch[0] <= 9830) // 0.6
+ voice_decision = DECISION_NOISE;
+ else
+ voice_decision = DECISION_INTERMEDIATE;
+
+ for(i=0, low_gain_pitch_cnt=0; i<6; i++)
+ if(past_gain_pitch[i] < 9830)
+ low_gain_pitch_cnt++;
+
+ if(low_gain_pitch_cnt > 2 && !onset)
+ voice_decision = DECISION_NOISE;
+
+ if(!onset && voice_decision > prev_voice_decision + 1)
+ voice_decision--;
+
+ if(onset && voice_decision < DECISION_VOICE)
+ voice_decision++;
+
+ return voice_decision;
+}
+
+static int32_t scalarproduct_int16_c(const int16_t * v1, const int16_t * v2, int order)
+{
+ int res = 0;
+
+ while (order--)
+ res += *v1++ * *v2++;
+
+ return res;
+}
+
+static av_cold int decoder_init(AVCodecContext * avctx)
+{
+ G729Context* ctx = avctx->priv_data;
+ int i,k;
+
+ if (avctx->channels != 1) {
+ av_log(avctx, AV_LOG_ERROR, "Only mono sound is supported (requested channels: %d).\n", avctx->channels);
+ return AVERROR(EINVAL);
+ }
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+
+ /* Both 8kbit/s and 6.4kbit/s modes uses two subframes per frame. */
+ avctx->frame_size = SUBFRAME_SIZE << 1;
+
+ ctx->gain_coeff = 16384; // 1.0 in (1.14)
+
+ for (k = 0; k < MA_NP + 1; k++) {
+ ctx->past_quantizer_outputs[k] = ctx->past_quantizer_output_buf[k];
+ for (i = 1; i < 11; i++)
+ ctx->past_quantizer_outputs[k][i - 1] = (18717 * i) >> 3;
+ }
+
+ ctx->lsp[0] = ctx->lsp_buf[0];
+ ctx->lsp[1] = ctx->lsp_buf[1];
+ memcpy(ctx->lsp[0], lsp_init, 10 * sizeof(int16_t));
+
+ ctx->exc = &ctx->exc_base[PITCH_DELAY_MAX+INTERPOL_LEN];
+
+ ctx->pitch_delay_int_prev = PITCH_DELAY_MIN;
+
+ /* random seed initialization */
+ ctx->rand_value = 21845;
+
+ /* quantized prediction error */
+ for(i=0; i<4; i++)
+ ctx->quant_energy[i] = -14336; // -14 in (5.10)
+
+ ff_audiodsp_init(&ctx->adsp);
+ ctx->adsp.scalarproduct_int16 = scalarproduct_int16_c;
+
+ return 0;
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
+ AVPacket *avpkt)
+{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ int16_t *out_frame;
+ GetBitContext gb;
+ const G729FormatDescription *format;
+ int frame_erasure = 0; ///< frame erasure detected during decoding
+ int bad_pitch = 0; ///< parity check failed
+ int i;
+ int16_t *tmp;
+ G729Formats packet_type;
+ G729Context *ctx = avctx->priv_data;
+ int16_t lp[2][11]; // (3.12)
+ uint8_t ma_predictor; ///< switched MA predictor of LSP quantizer
+ uint8_t quantizer_1st; ///< first stage vector of quantizer
+ uint8_t quantizer_2nd_lo; ///< second stage lower vector of quantizer (size in bits)
+ uint8_t quantizer_2nd_hi; ///< second stage higher vector of quantizer (size in bits)
+
+ int pitch_delay_int[2]; // pitch delay, integer part
+ int pitch_delay_3x; // pitch delay, multiplied by 3
+ int16_t fc[SUBFRAME_SIZE]; // fixed-codebook vector
+ int16_t synth[SUBFRAME_SIZE+10]; // fixed-codebook vector
+ int j, ret;
+ int gain_before, gain_after;
+ int is_periodic = 0; // whether one of the subframes is declared as periodic or not
+ AVFrame *frame = data;
+
+ frame->nb_samples = SUBFRAME_SIZE<<1;
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+ return ret;
+ out_frame = (int16_t*) frame->data[0];
+
+ if (buf_size % 10 == 0) {
+ packet_type = FORMAT_G729_8K;
+ format = &format_g729_8k;
+ //Reset voice decision
+ ctx->onset = 0;
+ ctx->voice_decision = DECISION_VOICE;
+ av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729 @ 8kbit/s");
+ } else if (buf_size == 8) {
+ packet_type = FORMAT_G729D_6K4;
+ format = &format_g729d_6k4;
+ av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729D @ 6.4kbit/s");
+ } else {
+ av_log(avctx, AV_LOG_ERROR, "Packet size %d is unknown.\n", buf_size);
+ return AVERROR_INVALIDDATA;
+ }
+
+ for (i=0; i < buf_size; i++)
+ frame_erasure |= buf[i];
+ frame_erasure = !frame_erasure;
+
+ init_get_bits(&gb, buf, 8*buf_size);
+
+ ma_predictor = get_bits(&gb, 1);
+ quantizer_1st = get_bits(&gb, VQ_1ST_BITS);
+ quantizer_2nd_lo = get_bits(&gb, VQ_2ND_BITS);
+ quantizer_2nd_hi = get_bits(&gb, VQ_2ND_BITS);
+
+ if(frame_erasure)
+ lsf_restore_from_previous(ctx->lsfq, ctx->past_quantizer_outputs,
+ ctx->ma_predictor_prev);
+ else {
+ lsf_decode(ctx->lsfq, ctx->past_quantizer_outputs,
+ ma_predictor,
+ quantizer_1st, quantizer_2nd_lo, quantizer_2nd_hi);
+ ctx->ma_predictor_prev = ma_predictor;
+ }
+
+ tmp = ctx->past_quantizer_outputs[MA_NP];
+ memmove(ctx->past_quantizer_outputs + 1, ctx->past_quantizer_outputs,
+ MA_NP * sizeof(int16_t*));
+ ctx->past_quantizer_outputs[0] = tmp;
+
+ ff_acelp_lsf2lsp(ctx->lsp[1], ctx->lsfq, 10);
+
+ ff_acelp_lp_decode(&lp[0][0], &lp[1][0], ctx->lsp[1], ctx->lsp[0], 10);
+
+ FFSWAP(int16_t*, ctx->lsp[1], ctx->lsp[0]);
+
+ for (i = 0; i < 2; i++) {
+ int gain_corr_factor;
+
+ uint8_t ac_index; ///< adaptive codebook index
+ uint8_t pulses_signs; ///< fixed-codebook vector pulse signs
+ int fc_indexes; ///< fixed-codebook indexes
+ uint8_t gc_1st_index; ///< gain codebook (first stage) index
+ uint8_t gc_2nd_index; ///< gain codebook (second stage) index
+
+ ac_index = get_bits(&gb, format->ac_index_bits[i]);
+ if(!i && format->parity_bit)
+ bad_pitch = av_parity(ac_index >> 2) == get_bits1(&gb);
+ fc_indexes = get_bits(&gb, format->fc_indexes_bits);
+ pulses_signs = get_bits(&gb, format->fc_signs_bits);
+ gc_1st_index = get_bits(&gb, format->gc_1st_index_bits);
+ gc_2nd_index = get_bits(&gb, format->gc_2nd_index_bits);
+
+ if (frame_erasure)
+ pitch_delay_3x = 3 * ctx->pitch_delay_int_prev;
+ else if(!i) {
+ if (bad_pitch)
+ pitch_delay_3x = 3 * ctx->pitch_delay_int_prev;
+ else
+ pitch_delay_3x = ff_acelp_decode_8bit_to_1st_delay3(ac_index);
+ } else {
+ int pitch_delay_min = av_clip(ctx->pitch_delay_int_prev - 5,
+ PITCH_DELAY_MIN, PITCH_DELAY_MAX - 9);
+
+ if(packet_type == FORMAT_G729D_6K4)
+ pitch_delay_3x = ff_acelp_decode_4bit_to_2nd_delay3(ac_index, pitch_delay_min);
+ else
+ pitch_delay_3x = ff_acelp_decode_5_6_bit_to_2nd_delay3(ac_index, pitch_delay_min);
+ }
+
+ /* Round pitch delay to nearest (used everywhere except ff_acelp_interpolate). */
+ pitch_delay_int[i] = (pitch_delay_3x + 1) / 3;
+ if (pitch_delay_int[i] > PITCH_DELAY_MAX) {
+ av_log(avctx, AV_LOG_WARNING, "pitch_delay_int %d is too large\n", pitch_delay_int[i]);
+ pitch_delay_int[i] = PITCH_DELAY_MAX;
+ }
+
+ if (frame_erasure) {
+ ctx->rand_value = g729_prng(ctx->rand_value);
+ fc_indexes = av_mod_uintp2(ctx->rand_value, format->fc_indexes_bits);
+
+ ctx->rand_value = g729_prng(ctx->rand_value);
+ pulses_signs = ctx->rand_value;
+ }
+
+
+ memset(fc, 0, sizeof(int16_t) * SUBFRAME_SIZE);
+ switch (packet_type) {
+ case FORMAT_G729_8K:
+ ff_acelp_fc_pulse_per_track(fc, ff_fc_4pulses_8bits_tracks_13,
+ ff_fc_4pulses_8bits_track_4,
+ fc_indexes, pulses_signs, 3, 3);
+ break;
+ case FORMAT_G729D_6K4:
+ ff_acelp_fc_pulse_per_track(fc, ff_fc_2pulses_9bits_track1_gray,
+ ff_fc_2pulses_9bits_track2_gray,
+ fc_indexes, pulses_signs, 1, 4);
+ break;
+ }
+
+ /*
+ This filter enhances harmonic components of the fixed-codebook vector to
+ improve the quality of the reconstructed speech.
+
+ / fc_v[i], i < pitch_delay
+ fc_v[i] = <
+ \ fc_v[i] + gain_pitch * fc_v[i-pitch_delay], i >= pitch_delay
+ */
+ ff_acelp_weighted_vector_sum(fc + pitch_delay_int[i],
+ fc + pitch_delay_int[i],
+ fc, 1 << 14,
+ av_clip(ctx->past_gain_pitch[0], SHARP_MIN, SHARP_MAX),
+ 0, 14,
+ SUBFRAME_SIZE - pitch_delay_int[i]);
+
+ memmove(ctx->past_gain_pitch+1, ctx->past_gain_pitch, 5 * sizeof(int16_t));
+ ctx->past_gain_code[1] = ctx->past_gain_code[0];
+
+ if (frame_erasure) {
+ ctx->past_gain_pitch[0] = (29491 * ctx->past_gain_pitch[0]) >> 15; // 0.90 (0.15)
+ ctx->past_gain_code[0] = ( 2007 * ctx->past_gain_code[0] ) >> 11; // 0.98 (0.11)
+
+ gain_corr_factor = 0;
+ } else {
+ if (packet_type == FORMAT_G729D_6K4) {
+ ctx->past_gain_pitch[0] = cb_gain_1st_6k4[gc_1st_index][0] +
+ cb_gain_2nd_6k4[gc_2nd_index][0];
+ gain_corr_factor = cb_gain_1st_6k4[gc_1st_index][1] +
+ cb_gain_2nd_6k4[gc_2nd_index][1];
+
+ /* Without check below overflow can occur in ff_acelp_update_past_gain.
+ It is not issue for G.729, because gain_corr_factor in it's case is always
+ greater than 1024, while in G.729D it can be even zero. */
+ gain_corr_factor = FFMAX(gain_corr_factor, 1024);
+#ifndef G729_BITEXACT
+ gain_corr_factor >>= 1;
+#endif
+ } else {
+ ctx->past_gain_pitch[0] = cb_gain_1st_8k[gc_1st_index][0] +
+ cb_gain_2nd_8k[gc_2nd_index][0];
+ gain_corr_factor = cb_gain_1st_8k[gc_1st_index][1] +
+ cb_gain_2nd_8k[gc_2nd_index][1];
+ }
+
+ /* Decode the fixed-codebook gain. */
+ ctx->past_gain_code[0] = ff_acelp_decode_gain_code(&ctx->adsp, gain_corr_factor,
+ fc, MR_ENERGY,
+ ctx->quant_energy,
+ ma_prediction_coeff,
+ SUBFRAME_SIZE, 4);
+#ifdef G729_BITEXACT
+ /*
+ This correction required to get bit-exact result with
+ reference code, because gain_corr_factor in G.729D is
+ two times larger than in original G.729.
+
+ If bit-exact result is not issue then gain_corr_factor
+ can be simpler divided by 2 before call to g729_get_gain_code
+ instead of using correction below.
+ */
+ if (packet_type == FORMAT_G729D_6K4) {
+ gain_corr_factor >>= 1;
+ ctx->past_gain_code[0] >>= 1;
+ }
+#endif
+ }
+ ff_acelp_update_past_gain(ctx->quant_energy, gain_corr_factor, 2, frame_erasure);
+
+ /* Routine requires rounding to lowest. */
+ ff_acelp_interpolate(ctx->exc + i * SUBFRAME_SIZE,
+ ctx->exc + i * SUBFRAME_SIZE - pitch_delay_3x / 3,
+ ff_acelp_interp_filter, 6,
+ (pitch_delay_3x % 3) << 1,
+ 10, SUBFRAME_SIZE);
+
+ ff_acelp_weighted_vector_sum(ctx->exc + i * SUBFRAME_SIZE,
+ ctx->exc + i * SUBFRAME_SIZE, fc,
+ (!ctx->was_periodic && frame_erasure) ? 0 : ctx->past_gain_pitch[0],
+ ( ctx->was_periodic && frame_erasure) ? 0 : ctx->past_gain_code[0],
+ 1 << 13, 14, SUBFRAME_SIZE);
+
+ memcpy(synth, ctx->syn_filter_data, 10 * sizeof(int16_t));
+
+ if (ff_celp_lp_synthesis_filter(
+ synth+10,
+ &lp[i][1],
+ ctx->exc + i * SUBFRAME_SIZE,
+ SUBFRAME_SIZE,
+ 10,
+ 1,
+ 0,
+ 0x800))
+ /* Overflow occurred, downscale excitation signal... */
+ for (j = 0; j < 2 * SUBFRAME_SIZE + PITCH_DELAY_MAX + INTERPOL_LEN; j++)
+ ctx->exc_base[j] >>= 2;
+
+ /* ... and make synthesis again. */
+ if (packet_type == FORMAT_G729D_6K4) {
+ int16_t exc_new[SUBFRAME_SIZE];
+
+ ctx->onset = g729d_onset_decision(ctx->onset, ctx->past_gain_code);
+ ctx->voice_decision = g729d_voice_decision(ctx->onset, ctx->voice_decision, ctx->past_gain_pitch);
+
+ g729d_get_new_exc(exc_new, ctx->exc + i * SUBFRAME_SIZE, fc, ctx->voice_decision, ctx->past_gain_code[0], SUBFRAME_SIZE);
+
+ ff_celp_lp_synthesis_filter(
+ synth+10,
+ &lp[i][1],
+ exc_new,
+ SUBFRAME_SIZE,
+ 10,
+ 0,
+ 0,
+ 0x800);
+ } else {
+ ff_celp_lp_synthesis_filter(
+ synth+10,
+ &lp[i][1],
+ ctx->exc + i * SUBFRAME_SIZE,
+ SUBFRAME_SIZE,
+ 10,
+ 0,
+ 0,
+ 0x800);
+ }
+ /* Save data (without postfilter) for use in next subframe. */
+ memcpy(ctx->syn_filter_data, synth+SUBFRAME_SIZE, 10 * sizeof(int16_t));
+
+ /* Calculate gain of unfiltered signal for use in AGC. */
+ gain_before = 0;
+ for (j = 0; j < SUBFRAME_SIZE; j++)
+ gain_before += FFABS(synth[j+10]);
+
+ /* Call postfilter and also update voicing decision for use in next frame. */
+ ff_g729_postfilter(
+ &ctx->adsp,
+ &ctx->ht_prev_data,
+ &is_periodic,
+ &lp[i][0],
+ pitch_delay_int[0],
+ ctx->residual,
+ ctx->res_filter_data,
+ ctx->pos_filter_data,
+ synth+10,
+ SUBFRAME_SIZE);
+
+ /* Calculate gain of filtered signal for use in AGC. */
+ gain_after = 0;
+ for(j=0; j<SUBFRAME_SIZE; j++)
+ gain_after += FFABS(synth[j+10]);
+
+ ctx->gain_coeff = ff_g729_adaptive_gain_control(
+ gain_before,
+ gain_after,
+ synth+10,
+ SUBFRAME_SIZE,
+ ctx->gain_coeff);
+
+ if (frame_erasure)
+ ctx->pitch_delay_int_prev = FFMIN(ctx->pitch_delay_int_prev + 1, PITCH_DELAY_MAX);
+ else
+ ctx->pitch_delay_int_prev = pitch_delay_int[i];
+
+ memcpy(synth+8, ctx->hpf_z, 2*sizeof(int16_t));
+ ff_acelp_high_pass_filter(
+ out_frame + i*SUBFRAME_SIZE,
+ ctx->hpf_f,
+ synth+10,
+ SUBFRAME_SIZE);
+ memcpy(ctx->hpf_z, synth+8+SUBFRAME_SIZE, 2*sizeof(int16_t));
+ }
+
+ ctx->was_periodic = is_periodic;
+
+ /* Save signal for use in next frame. */
+ memmove(ctx->exc_base, ctx->exc_base + 2 * SUBFRAME_SIZE, (PITCH_DELAY_MAX+INTERPOL_LEN)*sizeof(int16_t));
+
+ *got_frame_ptr = 1;
+ return packet_type == FORMAT_G729_8K ? 10 : 8;
+}
+
+AVCodec ff_g729_decoder = {
+ .name = "g729",
+ .long_name = NULL_IF_CONFIG_SMALL("G.729"),
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_G729,
+ .priv_data_size = sizeof(G729Context),
+ .init = decoder_init,
+ .decode = decode_frame,
+ .capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
+};
OpenPOWER on IntegriCloud