diff options
author | Michael Niedermayer <michaelni@gmx.at> | 2011-09-24 19:39:18 +0200 |
---|---|---|
committer | Michael Niedermayer <michaelni@gmx.at> | 2011-09-24 19:39:18 +0200 |
commit | 0b61af73823e88444b585c156d6c7b3677ce03bf (patch) | |
tree | eb0bc3f8437d2bc071b84d13a995b6ac7251e314 /libavcodec/g729dec.c | |
parent | 1aad9cd9d26adcca1d398a4cb3d67f89a6fa8967 (diff) | |
download | ffmpeg-streaming-0b61af73823e88444b585c156d6c7b3677ce03bf.zip ffmpeg-streaming-0b61af73823e88444b585c156d6c7b3677ce03bf.tar.gz |
Restore WIP g729 code that has been remvoed by diego biurrun.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/g729dec.c')
-rw-r--r-- | libavcodec/g729dec.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/libavcodec/g729dec.c b/libavcodec/g729dec.c new file mode 100644 index 0000000..c4a883f --- /dev/null +++ b/libavcodec/g729dec.c @@ -0,0 +1,331 @@ +/* + * G.729 decoder + * 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 <stdlib.h> +#include <inttypes.h> +#include <limits.h> +#include <stdio.h> +#include <string.h> +#include <math.h> +#include <assert.h> + +#include "avcodec.h" +#include "libavutil/avutil.h" +#include "get_bits.h" + +#include "lsp.h" +#include "celp_math.h" +#include "acelp_filters.h" +#include "acelp_pitch_delay.h" +#include "acelp_vectors.h" +#include "g729data.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 + +/** + * 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 + +/** + * subframe size + */ +#define SUBFRAME_SIZE 40 + + +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 { + 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 +} 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; +} + +/** + * Get parity bit of bit 2..7 + */ +static inline int get_parity(uint8_t value) +{ + return (0x6996966996696996ULL >> (value >> 2)) & 1; +} + +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; + } + + /* Rotate past_quantizer_outputs. */ + memmove(past_quantizer_outputs + 1, past_quantizer_outputs, MA_NP * sizeof(int16_t*)); + past_quantizer_outputs[0] = quantizer_output; + + ff_acelp_reorder_lsf(lsfq, LSFQ_DIFF_MIN, LSFQ_MIN, LSFQ_MAX, 10); +} + +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); + } + + /* Both 8kbit/s and 6.4kbit/s modes uses two subframes per frame. */ + avctx->frame_size = SUBFRAME_SIZE << 1; + + 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)); + + return 0; +} + +static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, + AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; + int16_t *out_frame = data; + GetBitContext gb; + G729FormatDescription format; + int frame_erasure = 0; ///< frame erasure detected during decoding + int bad_pitch = 0; ///< parity check failed + int i; + 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; // pitch delay, integer part + int pitch_delay_3x; // pitch delay, multiplied by 3 + + if (*data_size < SUBFRAME_SIZE << 2) { + av_log(avctx, AV_LOG_ERROR, "Error processing packet: output buffer too small\n"); + return AVERROR(EIO); + } + + if (buf_size == 10) { + format = format_g729_8k; + av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729 @ 8kbit/s"); + } else if (buf_size == 8) { + 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, 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); + + lsf_decode(ctx->lsfq, ctx->past_quantizer_outputs, + ma_predictor, + quantizer_1st, quantizer_2nd_lo, quantizer_2nd_hi); + + 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++) { + 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 = get_parity(ac_index) == 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(!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 = (pitch_delay_3x + 1) / 3; + + ff_acelp_weighted_vector_sum(fc + pitch_delay_int, + fc + pitch_delay_int, + fc, 1 << 14, + av_clip(ctx->gain_pitch, SHARP_MIN, SHARP_MAX), + 0, 14, + SUBFRAME_SIZE - pitch_delay_int); + + if (frame_erasure) { + ctx->gain_pitch = (29491 * ctx->gain_pitch) >> 15; // 0.90 (0.15) + ctx->gain_code = ( 2007 * ctx->gain_code ) >> 11; // 0.98 (0.11) + + gain_corr_factor = 0; + } else { + ctx->gain_pitch = 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]; + + ff_acelp_weighted_vector_sum(ctx->exc + i * SUBFRAME_SIZE, + ctx->exc + i * SUBFRAME_SIZE, fc, + (!voicing && frame_erasure) ? 0 : ctx->gain_pitch, + ( voicing && frame_erasure) ? 0 : ctx->gain_code, + 1 << 13, 14, SUBFRAME_SIZE); + + ctx->pitch_delay_int_prev = pitch_delay_int; + } + + *data_size = SUBFRAME_SIZE << 2; + return buf_size; +} + +AVCodec ff_g729_decoder = +{ + "g729", + AVMEDIA_TYPE_AUDIO, + CODEC_ID_G729, + sizeof(G729Context), + decoder_init, + NULL, + NULL, + decode_frame, + .long_name = NULL_IF_CONFIG_SMALL("G.729"), +}; |