| 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 | |
| 27 | typedef struct G729DemuxerContext { |
| 28 | AVClass *class; |
| 29 | int bit_rate; |
| 30 | } G729DemuxerContext; |
| 31 | |
| 32 | static 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 | } |
| 67 | static 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 | |
| 82 | static 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 | |
| 87 | static 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 | |
| 94 | AVInputFormat 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 | }; |