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omaenc.c
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1 /*
2  * Sony OpenMG (OMA) muxer
3  *
4  * Copyright (c) 2011 Michael Karcher
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "avformat.h"
24 #include "avio_internal.h"
25 #include "id3v2.h"
26 #include "internal.h"
27 #include "oma.h"
28 #include "rawenc.h"
29 
31 {
32  int i;
33  AVCodecContext *format;
34  int srate_index;
35  int isjointstereo;
36 
37  format = s->streams[0]->codec;
38  /* check for support of the format first */
39 
40  for (srate_index = 0; ; srate_index++) {
41  if (ff_oma_srate_tab[srate_index] == 0) {
42  av_log(s, AV_LOG_ERROR, "Sample rate %d not supported in OpenMG audio\n",
43  format->sample_rate);
44  return AVERROR(EINVAL);
45  }
46 
47  if (ff_oma_srate_tab[srate_index] * 100 == format->sample_rate)
48  break;
49  }
50 
51  /* Metadata; OpenMG does not support ID3v2.4 */
53 
54  ffio_wfourcc(s->pb, "EA3\0");
55  avio_w8(s->pb, EA3_HEADER_SIZE >> 7);
56  avio_w8(s->pb, EA3_HEADER_SIZE & 0x7F);
57  avio_wl16(s->pb, 0xFFFF); /* not encrypted */
58  for (i = 0; i < 6; i++)
59  avio_wl32(s->pb, 0); /* Padding + DRM id */
60 
61  switch(format->codec_tag) {
62  case OMA_CODECID_ATRAC3:
63  if (format->channels != 2) {
64  av_log(s, AV_LOG_ERROR, "ATRAC3 in OMA is only supported with 2 channels\n");
65  return AVERROR(EINVAL);
66  }
67  if (format->extradata_size == 14) /* WAV format extradata */
68  isjointstereo = format->extradata[6] != 0;
69  else if(format->extradata_size == 10) /* RM format extradata */
70  isjointstereo = format->extradata[8] == 0x12;
71  else {
72  av_log(s, AV_LOG_ERROR, "ATRAC3: Unsupported extradata size\n");
73  return AVERROR(EINVAL);
74  }
75  avio_wb32(s->pb, (OMA_CODECID_ATRAC3 << 24) |
76  (isjointstereo << 17) |
77  (srate_index << 13) |
78  (format->block_align/8));
79  break;
81  avio_wb32(s->pb, (OMA_CODECID_ATRAC3P << 24) |
82  (srate_index << 13) |
83  (format->channels << 10) |
84  (format->block_align/8 - 1));
85  break;
86  default:
87  av_log(s, AV_LOG_ERROR, "unsupported codec tag %d for write\n",
88  format->codec_tag);
89  return AVERROR(EINVAL);
90  }
91  for (i = 0; i < (EA3_HEADER_SIZE - 36)/4; i++)
92  avio_wl32(s->pb, 0); /* Padding */
93 
94  return 0;
95 }
96 
98  .name = "oma",
99  .long_name = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
100  .mime_type = "audio/x-oma",
101  .extensions = "oma",
102  .audio_codec = AV_CODEC_ID_ATRAC3,
103  .write_header = oma_write_header,
104  .write_packet = ff_raw_write_packet,
105  .codec_tag = (const AVCodecTag* const []){ff_oma_codec_tags, 0},
106 };