1/* 2 * G.729 decoder 3 * Copyright (c) 2008 Vladimir Voroshilov 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21#include <stdlib.h> 22#include <inttypes.h> 23#include <limits.h> 24#include <stdio.h> 25#include <string.h> 26#include <math.h> 27#include <assert.h> 28 29#include "avcodec.h" 30#include "libavutil/avutil.h" 31#include "bitstream.h" 32 33#include "g729.h" 34#include "lsp.h" 35#include "celp_math.h" 36#include "acelp_filters.h" 37#include "acelp_pitch_delay.h" 38#include "acelp_vectors.h" 39#include "g729data.h" 40 41/** 42 * minimum quantized LSF value (3.2.4) 43 * 0.005 in Q13 44 */ 45#define LSFQ_MIN 40 46 47/** 48 * maximum quantized LSF value (3.2.4) 49 * 3.135 in Q13 50 */ 51#define LSFQ_MAX 25681 52 53/** 54 * minimum LSF distance (3.2.4) 55 * 0.0391 in Q13 56 */ 57#define LSFQ_DIFF_MIN 321 58 59/** 60 * minimum gain pitch value (3.8, Equation 47) 61 * 0.2 in (1.14) 62 */ 63#define SHARP_MIN 3277 64 65/** 66 * maximum gain pitch value (3.8, Equation 47) 67 * (EE) This does not comply with the specification. 68 * Specification says about 0.8, which should be 69 * 13107 in (1.14), but reference C code uses 70 * 13017 (equals to 0.7945) instead of it. 71 */ 72#define SHARP_MAX 13017 73 74typedef struct 75{ 76 int sample_rate; 77 uint8_t packed_frame_size; ///< input frame size(in bytes) 78 uint8_t unpacked_frame_size;///< output frame size (in bytes) 79 uint8_t fc_indexes_bits; ///< size (in bits) of fixed-codebook index entry 80 81 /// mr_energy = mean_energy + 10 * log10(2^26 * subframe_size) in (7.13) 82 int mr_energy; 83} G729_format_description; 84 85/** 86 * \brief pseudo random number generator 87 */ 88static inline uint16_t g729_random(uint16_t value) 89{ 90 return 31821 * value + 13849; 91} 92 93/** 94 * Get parity bit of bit 2..7 95 */ 96static inline int g729_get_parity(uint8_t value) 97{ 98 return (0x6996966996696996ULL >> (value >> 2)) & 1; 99} 100 101 if(avctx->channels != 1) 102 { 103 av_log(avctx, AV_LOG_ERROR, "Only mono sound is supported (requested channels: %d).\n", avctx->channels); 104 return AVERROR_NOFMT; 105 } 106 107 ff_acelp_weighted_vector_sum( 108 fc + pitch_delay_int[i], 109 fc + pitch_delay_int[i], 110 fc, 111 1 << 14, 112 av_clip(ctx->gain_pitch, SHARP_MIN, SHARP_MAX), 113 0, 114 14, 115 ctx->subframe_size - pitch_delay_int[i]); 116 117 if(ctx->frame_erasure) 118 { 119 ctx->gain_pitch = (29491 * ctx->gain_pitch) >> 15; // 0.9 (0.15) 120 ctx->gain_code = (2007 * ctx->gain_code) >> 11; // 0.98 in (0.11) 121 122 gain_corr_factor = 0; 123 } 124 else 125 { 126 ctx->gain_pitch = cb_gain_1st_8k[parm->gc_1st_index[i]][0] + 127 cb_gain_2nd_8k[parm->gc_2nd_index[i]][0]; 128 gain_corr_factor = cb_gain_1st_8k[parm->gc_1st_index[i]][1] + 129 cb_gain_2nd_8k[parm->gc_2nd_index[i]][1]; 130 131 ff_acelp_weighted_vector_sum( 132 ctx->exc + i * ctx->subframe_size, 133 ctx->exc + i * ctx->subframe_size, 134 fc, 135 (!voicing && ctx->frame_erasure) ? 0 : ctx->gain_pitch, 136 ( voicing && ctx->frame_erasure) ? 0 : ctx->gain_code, 137 1<<13, 138 14, 139 ctx->subframe_size); 140 141 if (buf_size<packed_frame_size) 142 { 143 av_log(avctx, AV_LOG_ERROR, "Error processing packet: packet size too small\n"); 144 return AVERROR(EIO); 145 } 146 if (*data_size<unpacked_frame_size) 147 { 148 av_log(avctx, AV_LOG_ERROR, "Error processing packet: output buffer too small\n"); 149 return AVERROR(EIO); 150 } 151 152AVCodec g729_decoder = 153{ 154 "g729", 155 CODEC_TYPE_AUDIO, 156 CODEC_ID_G729, 157 sizeof(G729_Context), 158 ff_g729_decoder_init, 159 NULL, 160 NULL, 161 ff_g729_decode_frame, 162 .long_name = NULL_IF_CONFIG_SMALL("G.729"), 163}; 164