1/* 2 * Copyright (C) 2008 David Conrad 3 * 4 * This file is part of FFmpeg. 5 * 6 * FFmpeg is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * FFmpeg is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with FFmpeg; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21#include "avcodec.h" 22#include <speex/speex.h> 23#include <speex/speex_header.h> 24#include <speex/speex_stereo.h> 25#include <speex/speex_callbacks.h> 26 27typedef struct { 28 SpeexBits bits; 29 SpeexStereoState stereo; 30 void *dec_state; 31 SpeexHeader *header; 32 int frame_size; 33} LibSpeexContext; 34 35 36static av_cold int libspeex_decode_init(AVCodecContext *avctx) 37{ 38 LibSpeexContext *s = avctx->priv_data; 39 const SpeexMode *mode; 40 41 // defaults in the case of a missing header 42 if (avctx->sample_rate <= 8000) 43 mode = &speex_nb_mode; 44 else if (avctx->sample_rate <= 16000) 45 mode = &speex_wb_mode; 46 else 47 mode = &speex_uwb_mode; 48 49 if (avctx->extradata_size >= 80) 50 s->header = speex_packet_to_header(avctx->extradata, avctx->extradata_size); 51 52 avctx->sample_fmt = SAMPLE_FMT_S16; 53 if (s->header) { 54 avctx->sample_rate = s->header->rate; 55 avctx->channels = s->header->nb_channels; 56 avctx->frame_size = s->frame_size = s->header->frame_size; 57 if (s->header->frames_per_packet) 58 avctx->frame_size *= s->header->frames_per_packet; 59 60 mode = speex_lib_get_mode(s->header->mode); 61 if (!mode) { 62 av_log(avctx, AV_LOG_ERROR, "Unknown Speex mode %d", s->header->mode); 63 return -1; 64 } 65 } else 66 av_log(avctx, AV_LOG_INFO, "Missing Speex header, assuming defaults.\n"); 67 68 if (avctx->channels > 2) { 69 av_log(avctx, AV_LOG_ERROR, "Only stereo and mono are supported.\n"); 70 return -1; 71 } 72 73 speex_bits_init(&s->bits); 74 s->dec_state = speex_decoder_init(mode); 75 if (!s->dec_state) { 76 av_log(avctx, AV_LOG_ERROR, "Error initializing libspeex decoder.\n"); 77 return -1; 78 } 79 80 if (!s->header) { 81 speex_decoder_ctl(s->dec_state, SPEEX_GET_FRAME_SIZE, &s->frame_size); 82 } 83 84 if (avctx->channels == 2) { 85 SpeexCallback callback; 86 callback.callback_id = SPEEX_INBAND_STEREO; 87 callback.func = speex_std_stereo_request_handler; 88 callback.data = &s->stereo; 89 s->stereo = (SpeexStereoState)SPEEX_STEREO_STATE_INIT; 90 speex_decoder_ctl(s->dec_state, SPEEX_SET_HANDLER, &callback); 91 } 92 return 0; 93} 94 95static int libspeex_decode_frame(AVCodecContext *avctx, 96 void *data, int *data_size, 97 AVPacket *avpkt) 98{ 99 const uint8_t *buf = avpkt->data; 100 int buf_size = avpkt->size; 101 LibSpeexContext *s = avctx->priv_data; 102 int16_t *output = data, *end; 103 int i, num_samples; 104 105 num_samples = s->frame_size * avctx->channels; 106 end = output + *data_size / sizeof(*output); 107 108 speex_bits_read_from(&s->bits, buf, buf_size); 109 110 for (i = 0; speex_bits_remaining(&s->bits) && output + num_samples < end; i++) { 111 int ret = speex_decode_int(s->dec_state, &s->bits, output); 112 if (ret <= -2) { 113 av_log(avctx, AV_LOG_ERROR, "Error decoding Speex frame.\n"); 114 return -1; 115 } else if (ret == -1) 116 // end of stream 117 break; 118 119 if (avctx->channels == 2) 120 speex_decode_stereo_int(output, s->frame_size, &s->stereo); 121 122 output += num_samples; 123 } 124 125 avctx->frame_size = s->frame_size * i; 126 *data_size = avctx->channels * avctx->frame_size * sizeof(*output); 127 return buf_size; 128} 129 130static av_cold int libspeex_decode_close(AVCodecContext *avctx) 131{ 132 LibSpeexContext *s = avctx->priv_data; 133 134 speex_header_free(s->header); 135 speex_bits_destroy(&s->bits); 136 speex_decoder_destroy(s->dec_state); 137 138 return 0; 139} 140 141AVCodec libspeex_decoder = { 142 "libspeex", 143 AVMEDIA_TYPE_AUDIO, 144 CODEC_ID_SPEEX, 145 sizeof(LibSpeexContext), 146 libspeex_decode_init, 147 NULL, 148 libspeex_decode_close, 149 libspeex_decode_frame, 150 .long_name = NULL_IF_CONFIG_SMALL("libspeex Speex"), 151}; 152