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au.c
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1 /*
2  * AU muxer and demuxer
3  * Copyright (c) 2001 Fabrice Bellard
4  *
5  * first version by Francois Revol <revol@free.fr>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /*
25  * Reference documents:
26  * http://www.opengroup.org/public/pubs/external/auformat.html
27  * http://www.goice.co.jp/member/mo/formats/au.html
28  */
29 
30 #include "avformat.h"
31 #include "internal.h"
32 #include "avio_internal.h"
33 #include "pcm.h"
34 #include "libavutil/avassert.h"
35 
36 /* if we don't know the size in advance */
37 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))
38 /* the specification requires an annotation field of at least eight bytes */
39 #define AU_HEADER_SIZE (24+8)
40 
41 static const AVCodecTag codec_au_tags[] = {
42  { AV_CODEC_ID_PCM_MULAW, 1 },
43  { AV_CODEC_ID_PCM_S8, 2 },
44  { AV_CODEC_ID_PCM_S16BE, 3 },
45  { AV_CODEC_ID_PCM_S24BE, 4 },
46  { AV_CODEC_ID_PCM_S32BE, 5 },
47  { AV_CODEC_ID_PCM_F32BE, 6 },
48  { AV_CODEC_ID_PCM_F64BE, 7 },
53  { AV_CODEC_ID_PCM_ALAW, 27 },
54  { AV_CODEC_ID_ADPCM_G726LE, MKBETAG('7','2','6','2') },
55  { AV_CODEC_ID_NONE, 0 },
56 };
57 
58 #if CONFIG_AU_DEMUXER
59 
60 static int au_probe(AVProbeData *p)
61 {
62  if (p->buf[0] == '.' && p->buf[1] == 's' &&
63  p->buf[2] == 'n' && p->buf[3] == 'd')
64  return AVPROBE_SCORE_MAX;
65  else
66  return 0;
67 }
68 
69 #define BLOCK_SIZE 1024
70 
71 static int au_read_header(AVFormatContext *s)
72 {
73  int size, data_size = 0;
74  unsigned int tag;
75  AVIOContext *pb = s->pb;
76  unsigned int id, channels, rate;
77  int bps;
78  enum AVCodecID codec;
79  AVStream *st;
80 
81  tag = avio_rl32(pb);
82  if (tag != MKTAG('.', 's', 'n', 'd'))
83  return AVERROR_INVALIDDATA;
84  size = avio_rb32(pb); /* header size */
85  data_size = avio_rb32(pb); /* data size in bytes */
86 
87  if (data_size < 0 && data_size != AU_UNKNOWN_SIZE) {
88  av_log(s, AV_LOG_ERROR, "Invalid negative data size '%d' found\n", data_size);
89  return AVERROR_INVALIDDATA;
90  }
91 
92  id = avio_rb32(pb);
93  rate = avio_rb32(pb);
94  channels = avio_rb32(pb);
95 
96  if (size > 24) {
97  /* skip unused data */
98  avio_skip(pb, size - 24);
99  }
100 
101  codec = ff_codec_get_id(codec_au_tags, id);
102 
103  if (codec == AV_CODEC_ID_NONE) {
104  avpriv_request_sample(s, "unknown or unsupported codec tag: %u", id);
105  return AVERROR_PATCHWELCOME;
106  }
107 
108  bps = av_get_bits_per_sample(codec);
109  if (codec == AV_CODEC_ID_ADPCM_G726LE) {
110  if (id == MKBETAG('7','2','6','2')) {
111  bps = 2;
112  } else {
113  const uint8_t bpcss[] = {4, 0, 3, 5};
114  av_assert0(id >= 23 && id < 23 + 4);
115  bps = bpcss[id - 23];
116  }
117  } else if (!bps) {
118  avpriv_request_sample(s, "Unknown bits per sample");
119  return AVERROR_PATCHWELCOME;
120  }
121 
122  if (channels == 0 || channels >= INT_MAX / (BLOCK_SIZE * bps >> 3)) {
123  av_log(s, AV_LOG_ERROR, "Invalid number of channels %u\n", channels);
124  return AVERROR_INVALIDDATA;
125  }
126 
127  if (rate == 0 || rate > INT_MAX) {
128  av_log(s, AV_LOG_ERROR, "Invalid sample rate: %u\n", rate);
129  return AVERROR_INVALIDDATA;
130  }
131 
132  st = avformat_new_stream(s, NULL);
133  if (!st)
134  return AVERROR(ENOMEM);
136  st->codec->codec_tag = id;
137  st->codec->codec_id = codec;
138  st->codec->channels = channels;
139  st->codec->sample_rate = rate;
141  st->codec->bit_rate = channels * rate * bps;
142  st->codec->block_align = FFMAX(bps * st->codec->channels / 8, 1);
143  if (data_size != AU_UNKNOWN_SIZE)
144  st->duration = (((int64_t)data_size)<<3) / (st->codec->channels * (int64_t)bps);
145 
146  st->start_time = 0;
147  avpriv_set_pts_info(st, 64, 1, rate);
148 
149  return 0;
150 }
151 
152 AVInputFormat ff_au_demuxer = {
153  .name = "au",
154  .long_name = NULL_IF_CONFIG_SMALL("Sun AU"),
155  .read_probe = au_probe,
156  .read_header = au_read_header,
157  .read_packet = ff_pcm_read_packet,
158  .read_seek = ff_pcm_read_seek,
159  .codec_tag = (const AVCodecTag* const []) { codec_au_tags, 0 },
160 };
161 
162 #endif /* CONFIG_AU_DEMUXER */
163 
164 #if CONFIG_AU_MUXER
165 
166 #include "rawenc.h"
167 
168 static int au_write_header(AVFormatContext *s)
169 {
170  AVIOContext *pb = s->pb;
171  AVCodecContext *enc = s->streams[0]->codec;
172 
173  if (s->nb_streams != 1) {
174  av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
175  return AVERROR(EINVAL);
176  }
177 
178  enc->codec_tag = ff_codec_get_tag(codec_au_tags, enc->codec_id);
179  if (!enc->codec_tag) {
180  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
181  return AVERROR(EINVAL);
182  }
183 
184  ffio_wfourcc(pb, ".snd"); /* magic number */
185  avio_wb32(pb, AU_HEADER_SIZE); /* header size */
186  avio_wb32(pb, AU_UNKNOWN_SIZE); /* data size */
187  avio_wb32(pb, enc->codec_tag); /* codec ID */
188  avio_wb32(pb, enc->sample_rate);
189  avio_wb32(pb, enc->channels);
190  avio_wb64(pb, 0); /* annotation field */
191  avio_flush(pb);
192 
193  return 0;
194 }
195 
196 static int au_write_trailer(AVFormatContext *s)
197 {
198  AVIOContext *pb = s->pb;
199  int64_t file_size = avio_tell(pb);
200 
201  if (s->pb->seekable && file_size < INT32_MAX) {
202  /* update file size */
203  avio_seek(pb, 8, SEEK_SET);
204  avio_wb32(pb, (uint32_t)(file_size - AU_HEADER_SIZE));
205  avio_seek(pb, file_size, SEEK_SET);
206  avio_flush(pb);
207  }
208 
209  return 0;
210 }
211 
212 AVOutputFormat ff_au_muxer = {
213  .name = "au",
214  .long_name = NULL_IF_CONFIG_SMALL("Sun AU"),
215  .mime_type = "audio/basic",
216  .extensions = "au",
217  .audio_codec = AV_CODEC_ID_PCM_S16BE,
218  .video_codec = AV_CODEC_ID_NONE,
219  .write_header = au_write_header,
220  .write_packet = ff_raw_write_packet,
221  .write_trailer = au_write_trailer,
222  .codec_tag = (const AVCodecTag* const []) { codec_au_tags, 0 },
223  .flags = AVFMT_NOTIMESTAMPS,
224 };
225 
226 #endif /* CONFIG_AU_MUXER */