1/* 2 * G.729 raw format demuxer 3 * Copyright (c) 2011 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 22#include "avformat.h" 23#include "internal.h" 24#include "libavutil/log.h" 25#include "libavutil/opt.h" 26 27typedef struct G729DemuxerContext { 28 AVClass *class; 29 int bit_rate; 30} G729DemuxerContext; 31 32static int g729_read_header(AVFormatContext *s) 33{ 34 AVStream* st; 35 G729DemuxerContext *s1 = s->priv_data; 36 37 st = avformat_new_stream(s, NULL); 38 if (!st) 39 return AVERROR(ENOMEM); 40 41 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 42 st->codec->codec_id = AV_CODEC_ID_G729; 43 st->codec->sample_rate = 8000; 44 st->codec->channels = 1; 45 46 if (s1 && s1->bit_rate) { 47 s->bit_rate = s1->bit_rate; 48 } 49 50 if (s->bit_rate == 0) { 51 av_log(s, AV_LOG_DEBUG, "No bitrate specified. Assuming 8000 b/s\n"); 52 s->bit_rate = 8000; 53 } 54 55 if (s->bit_rate == 6400) { 56 st->codec->block_align = 8; 57 } else if (s->bit_rate == 8000) { 58 st->codec->block_align = 10; 59 } else { 60 av_log(s, AV_LOG_ERROR, "Only 8000 b/s and 6400 b/s bitrates are supported. Provided: %d b/s\n", s->bit_rate); 61 return AVERROR_INVALIDDATA; 62 } 63 64 avpriv_set_pts_info(st, st->codec->block_align << 3, 1, st->codec->sample_rate); 65 return 0; 66} 67static int g729_read_packet(AVFormatContext *s, AVPacket *pkt) 68{ 69 int ret; 70 71 ret = av_get_packet(s->pb, pkt, s->streams[0]->codec->block_align); 72 73 pkt->stream_index = 0; 74 if (ret < 0) 75 return ret; 76 77 pkt->dts = pkt->pts = pkt->pos / s->streams[0]->codec->block_align; 78 79 return ret; 80} 81 82static const AVOption g729_options[] = { 83 { "bit_rate", "", offsetof(G729DemuxerContext, bit_rate), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM }, 84 { NULL }, 85}; 86 87static const AVClass g729_demuxer_class = { 88 .class_name = "g729 demuxer", 89 .item_name = av_default_item_name, 90 .option = g729_options, 91 .version = LIBAVUTIL_VERSION_INT, 92}; 93 94AVInputFormat ff_g729_demuxer = { 95 .name = "g729", 96 .long_name = NULL_IF_CONFIG_SMALL("G.729 raw format demuxer"), 97 .priv_data_size = sizeof(G729DemuxerContext), 98 .read_header = g729_read_header, 99 .read_packet = g729_read_packet, 100 .flags = AVFMT_GENERIC_INDEX, 101 .extensions = "g729", 102 .priv_class = &g729_demuxer_class, 103}; 104