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.
30 static const char AMR_header [] = "#!AMR\n";
31 static const char AMRWB_header [] = "#!AMR-WB\n";
34 static int amr_write_header(AVFormatContext *s)
36 AVIOContext *pb = s->pb;
37 AVCodecContext *enc = s->streams[0]->codec;
41 if (enc->codec_id == CODEC_ID_AMR_NB)
43 avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
45 else if(enc->codec_id == CODEC_ID_AMR_WB)
47 avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
57 static int amr_write_packet(AVFormatContext *s, AVPacket *pkt)
59 avio_write(s->pb, pkt->data, pkt->size);
63 #endif /* CONFIG_AMR_MUXER */
65 static int amr_probe(AVProbeData *p)
67 //Only check for "#!AMR" which could be amr-wb, amr-nb.
68 //This will also trigger multichannel files: "#!AMR_MC1.0\n" and
69 //"#!AMR-WB_MC1.0\n" (not supported)
71 if(memcmp(p->buf,AMR_header,5)==0)
72 return AVPROBE_SCORE_MAX;
78 static int amr_read_header(AVFormatContext *s,
79 AVFormatParameters *ap)
81 AVIOContext *pb = s->pb;
85 avio_read(pb, header, 6);
87 st = av_new_stream(s, 0);
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;
103 st->codec->frame_size = 320;
107 st->codec->codec_tag = MKTAG('s', 'a', 'm', 'r');
108 st->codec->codec_id = CODEC_ID_AMR_NB;
109 st->codec->sample_rate = 8000;
110 st->codec->frame_size = 160;
112 st->codec->channels = 1;
113 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
114 av_set_pts_info(st, 64, 1, st->codec->sample_rate);
119 static int amr_read_packet(AVFormatContext *s,
122 AVCodecContext *enc = s->streams[0]->codec;
123 int read, size = 0, toc, mode;
124 int64_t pos = avio_tell(s->pb);
131 //FIXME this is wrong, this should rather be in a AVParset
133 mode = (toc >> 3) & 0x0F;
135 if (enc->codec_id == CODEC_ID_AMR_NB)
137 static const uint8_t packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0};
139 size=packed_size[mode]+1;
141 else if(enc->codec_id == CODEC_ID_AMR_WB)
143 static uint8_t packed_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
145 size=packed_size[mode];
152 if ( (size==0) || av_new_packet(pkt, size))
157 /* Both AMR formats have 50 frames per second */
158 s->streams[0]->codec->bit_rate = size*8*50;
160 pkt->stream_index = 0;
163 pkt->duration= enc->codec_id == CODEC_ID_AMR_NB ? 160 : 320;
164 read = avio_read(s->pb, pkt->data+1, size-1);
175 #if CONFIG_AMR_DEMUXER
176 AVInputFormat ff_amr_demuxer = {
178 .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
179 .priv_data_size = 0, /*priv_data_size*/
180 .read_probe = amr_probe,
181 .read_header = amr_read_header,
182 .read_packet = amr_read_packet,
183 .flags = AVFMT_GENERIC_INDEX,
188 AVOutputFormat ff_amr_muxer = {
190 .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR file format"),
191 .mime_type = "audio/amr",
193 .audio_codec = CODEC_ID_AMR_NB,
194 .video_codec = CODEC_ID_NONE,
195 .write_header = amr_write_header,
196 .write_packet = amr_write_packet,