repositories / deb_ffmpeg.git / blame
| Commit | Line | Data |
|---|---|---|
| 2ba45a60 DM |
1 | /* |
| 2 | * RAW GSM demuxer | |
| 3 | * Copyright (c) 2011 Justin Ruggles | |
| 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 "libavutil/channel_layout.h" | |
| 23 | #include "libavutil/mathematics.h" | |
| 24 | #include "libavutil/opt.h" | |
| 25 | #include "avformat.h" | |
| 26 | #include "internal.h" | |
| 27 | ||
| 28 | #define GSM_BLOCK_SIZE 33 | |
| 29 | #define GSM_BLOCK_SAMPLES 160 | |
| 30 | #define GSM_SAMPLE_RATE 8000 | |
| 31 | ||
| 32 | typedef struct { | |
| 33 | AVClass *class; | |
| 34 | int sample_rate; | |
| 35 | } GSMDemuxerContext; | |
| 36 | ||
| 37 | static int gsm_read_packet(AVFormatContext *s, AVPacket *pkt) | |
| 38 | { | |
| 39 | int ret, size; | |
| 40 | ||
| 41 | size = GSM_BLOCK_SIZE; | |
| 42 | ||
| 43 | pkt->pos = avio_tell(s->pb); | |
| 44 | pkt->stream_index = 0; | |
| 45 | ||
| 46 | ret = av_get_packet(s->pb, pkt, size); | |
| 47 | if (ret < GSM_BLOCK_SIZE) { | |
| 48 | av_free_packet(pkt); | |
| 49 | return ret < 0 ? ret : AVERROR(EIO); | |
| 50 | } | |
| 51 | pkt->duration = 1; | |
| 52 | pkt->pts = pkt->pos / GSM_BLOCK_SIZE; | |
| 53 | ||
| 54 | return 0; | |
| 55 | } | |
| 56 | ||
| 57 | static int gsm_read_header(AVFormatContext *s) | |
| 58 | { | |
| 59 | GSMDemuxerContext *c = s->priv_data; | |
| 60 | AVStream *st = avformat_new_stream(s, NULL); | |
| 61 | if (!st) | |
| 62 | return AVERROR(ENOMEM); | |
| 63 | ||
| 64 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; | |
| 65 | st->codec->codec_id = s->iformat->raw_codec_id; | |
| 66 | st->codec->channels = 1; | |
| 67 | st->codec->channel_layout = AV_CH_LAYOUT_MONO; | |
| 68 | st->codec->sample_rate = c->sample_rate; | |
| 69 | st->codec->bit_rate = GSM_BLOCK_SIZE * 8 * c->sample_rate / GSM_BLOCK_SAMPLES; | |
| 70 | ||
| 71 | avpriv_set_pts_info(st, 64, GSM_BLOCK_SAMPLES, GSM_SAMPLE_RATE); | |
| 72 | ||
| 73 | return 0; | |
| 74 | } | |
| 75 | ||
| 76 | static const AVOption options[] = { | |
| 77 | { "sample_rate", "", offsetof(GSMDemuxerContext, sample_rate), | |
| 78 | AV_OPT_TYPE_INT, {.i64 = GSM_SAMPLE_RATE}, 1, INT_MAX / GSM_BLOCK_SIZE, | |
| 79 | AV_OPT_FLAG_DECODING_PARAM }, | |
| 80 | { NULL }, | |
| 81 | }; | |
| 82 | ||
| 83 | static const AVClass gsm_class = { | |
| 84 | .class_name = "gsm demuxer", | |
| 85 | .item_name = av_default_item_name, | |
| 86 | .option = options, | |
| 87 | .version = LIBAVUTIL_VERSION_INT, | |
| 88 | }; | |
| 89 | ||
| 90 | AVInputFormat ff_gsm_demuxer = { | |
| 91 | .name = "gsm", | |
| 92 | .long_name = NULL_IF_CONFIG_SMALL("raw GSM"), | |
| 93 | .priv_data_size = sizeof(GSMDemuxerContext), | |
| 94 | .read_header = gsm_read_header, | |
| 95 | .read_packet = gsm_read_packet, | |
| 96 | .flags = AVFMT_GENERIC_INDEX, | |
| 97 | .extensions = "gsm", | |
| 98 | .raw_codec_id = AV_CODEC_ID_GSM, | |
| 99 | .priv_class = &gsm_class, | |
| 100 | }; |