3 * Copyright (c) 2001 ffmpeg project
5 * This file is part of FFmpeg.
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.
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.
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
23 Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267
25 Only mono files are supported.
31 static const char AMR_header [] = "#!AMR\n";
32 static const char AMRWB_header [] = "#!AMR-WB\n";
35 static int amr_write_header(AVFormatContext *s)
37 AVIOContext *pb = s->pb;
38 AVCodecContext *enc = s->streams[0]->codec;
42 if (enc->codec_id == CODEC_ID_AMR_NB)
44 avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
46 else if(enc->codec_id == CODEC_ID_AMR_WB)
48 avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
58 static int amr_write_packet(AVFormatContext *s, AVPacket *pkt)
60 avio_write(s->pb, pkt->data, pkt->size);
64 #endif /* CONFIG_AMR_MUXER */
66 static int amr_probe(AVProbeData *p)
68 //Only check for "#!AMR" which could be amr-wb, amr-nb.
69 //This will also trigger multichannel files: "#!AMR_MC1.0\n" and
70 //"#!AMR-WB_MC1.0\n" (not supported)
72 if(memcmp(p->buf,AMR_header,5)==0)
73 return AVPROBE_SCORE_MAX;
79 static int amr_read_header(AVFormatContext *s)
81 AVIOContext *pb = s->pb;
85 avio_read(pb, header, 6);
87 st = avformat_new_stream(s, NULL);
90 return AVERROR(ENOMEM);
92 if(memcmp(header,AMR_header,6)!=0)
94 avio_read(pb, header+6, 3);
95 if(memcmp(header,AMRWB_header,9)!=0)
100 st->codec->codec_tag = MKTAG('s', 'a', 'w', 'b');
101 st->codec->codec_id = CODEC_ID_AMR_WB;
102 st->codec->sample_rate = 16000;
106 st->codec->codec_tag = MKTAG('s', 'a', 'm', 'r');
107 st->codec->codec_id = CODEC_ID_AMR_NB;
108 st->codec->sample_rate = 8000;
110 st->codec->channels = 1;
111 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
112 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
117 static int amr_read_packet(AVFormatContext *s,
120 AVCodecContext *enc = s->streams[0]->codec;
121 int read, size = 0, toc, mode;
122 int64_t pos = avio_tell(s->pb);
129 //FIXME this is wrong, this should rather be in a AVParset
131 mode = (toc >> 3) & 0x0F;
133 if (enc->codec_id == CODEC_ID_AMR_NB)
135 static const uint8_t packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0};
137 size=packed_size[mode]+1;
139 else if(enc->codec_id == CODEC_ID_AMR_WB)
141 static uint8_t packed_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
143 size=packed_size[mode];
150 if ( (size==0) || av_new_packet(pkt, size))
155 /* Both AMR formats have 50 frames per second */
156 s->streams[0]->codec->bit_rate = size*8*50;
158 pkt->stream_index = 0;
161 pkt->duration= enc->codec_id == CODEC_ID_AMR_NB ? 160 : 320;
162 read = avio_read(s->pb, pkt->data+1, size-1);
173 #if CONFIG_AMR_DEMUXER
174 AVInputFormat ff_amr_demuxer = {
176 .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
177 .read_probe = amr_probe,
178 .read_header = amr_read_header,
179 .read_packet = amr_read_packet,
180 .flags = AVFMT_GENERIC_INDEX,
185 AVOutputFormat ff_amr_muxer = {
187 .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
188 .mime_type = "audio/amr",
190 .audio_codec = CODEC_ID_AMR_NB,
191 .video_codec = CODEC_ID_NONE,
192 .write_header = amr_write_header,
193 .write_packet = amr_write_packet,