| 1 | /* |
| 2 | * iLBC storage file format |
| 3 | * Copyright (c) 2012 Martin Storsjo |
| 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 | |
| 25 | static const char mode20_header[] = "#!iLBC20\n"; |
| 26 | static const char mode30_header[] = "#!iLBC30\n"; |
| 27 | |
| 28 | static int ilbc_write_header(AVFormatContext *s) |
| 29 | { |
| 30 | AVIOContext *pb = s->pb; |
| 31 | AVCodecContext *enc; |
| 32 | |
| 33 | if (s->nb_streams != 1) { |
| 34 | av_log(s, AV_LOG_ERROR, "Unsupported number of streams\n"); |
| 35 | return AVERROR(EINVAL); |
| 36 | } |
| 37 | enc = s->streams[0]->codec; |
| 38 | |
| 39 | if (enc->codec_id != AV_CODEC_ID_ILBC) { |
| 40 | av_log(s, AV_LOG_ERROR, "Unsupported codec\n"); |
| 41 | return AVERROR(EINVAL); |
| 42 | } |
| 43 | |
| 44 | if (enc->block_align == 50) { |
| 45 | avio_write(pb, mode30_header, sizeof(mode30_header) - 1); |
| 46 | } else if (enc->block_align == 38) { |
| 47 | avio_write(pb, mode20_header, sizeof(mode20_header) - 1); |
| 48 | } else { |
| 49 | av_log(s, AV_LOG_ERROR, "Unsupported mode\n"); |
| 50 | return AVERROR(EINVAL); |
| 51 | } |
| 52 | avio_flush(pb); |
| 53 | return 0; |
| 54 | } |
| 55 | |
| 56 | static int ilbc_write_packet(AVFormatContext *s, AVPacket *pkt) |
| 57 | { |
| 58 | avio_write(s->pb, pkt->data, pkt->size); |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | static int ilbc_probe(AVProbeData *p) |
| 63 | { |
| 64 | // Only check for "#!iLBC" which matches both formats |
| 65 | if (!memcmp(p->buf, mode20_header, 6)) |
| 66 | return AVPROBE_SCORE_MAX; |
| 67 | else |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static int ilbc_read_header(AVFormatContext *s) |
| 72 | { |
| 73 | AVIOContext *pb = s->pb; |
| 74 | AVStream *st; |
| 75 | uint8_t header[9]; |
| 76 | |
| 77 | avio_read(pb, header, 9); |
| 78 | |
| 79 | st = avformat_new_stream(s, NULL); |
| 80 | if (!st) |
| 81 | return AVERROR(ENOMEM); |
| 82 | st->codec->codec_id = AV_CODEC_ID_ILBC; |
| 83 | st->codec->sample_rate = 8000; |
| 84 | st->codec->channels = 1; |
| 85 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 86 | st->start_time = 0; |
| 87 | avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); |
| 88 | if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) { |
| 89 | st->codec->block_align = 38; |
| 90 | st->codec->bit_rate = 15200; |
| 91 | } else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) { |
| 92 | st->codec->block_align = 50; |
| 93 | st->codec->bit_rate = 13333; |
| 94 | } else { |
| 95 | av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n"); |
| 96 | return AVERROR_INVALIDDATA; |
| 97 | } |
| 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | static int ilbc_read_packet(AVFormatContext *s, |
| 103 | AVPacket *pkt) |
| 104 | { |
| 105 | AVCodecContext *enc = s->streams[0]->codec; |
| 106 | int ret; |
| 107 | |
| 108 | if ((ret = av_new_packet(pkt, enc->block_align)) < 0) |
| 109 | return ret; |
| 110 | |
| 111 | pkt->stream_index = 0; |
| 112 | pkt->pos = avio_tell(s->pb); |
| 113 | pkt->duration = enc->block_align == 38 ? 160 : 240; |
| 114 | if ((ret = avio_read(s->pb, pkt->data, enc->block_align)) != enc->block_align) { |
| 115 | av_free_packet(pkt); |
| 116 | return ret < 0 ? ret : AVERROR(EIO); |
| 117 | } |
| 118 | |
| 119 | return 0; |
| 120 | } |
| 121 | |
| 122 | AVInputFormat ff_ilbc_demuxer = { |
| 123 | .name = "ilbc", |
| 124 | .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"), |
| 125 | .read_probe = ilbc_probe, |
| 126 | .read_header = ilbc_read_header, |
| 127 | .read_packet = ilbc_read_packet, |
| 128 | .flags = AVFMT_GENERIC_INDEX, |
| 129 | }; |
| 130 | |
| 131 | AVOutputFormat ff_ilbc_muxer = { |
| 132 | .name = "ilbc", |
| 133 | .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"), |
| 134 | .mime_type = "audio/iLBC", |
| 135 | .extensions = "lbc", |
| 136 | .audio_codec = AV_CODEC_ID_ILBC, |
| 137 | .write_header = ilbc_write_header, |
| 138 | .write_packet = ilbc_write_packet, |
| 139 | .flags = AVFMT_NOTIMESTAMPS, |
| 140 | }; |