FFmpeg: libavformat/omaenc.c Source File

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libavformat

omaenc.c

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1 /*

2 * Sony OpenMG (OMA) muxer

3 *

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 */

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"

30 static av_cold int oma_write_header(AVFormatContext *s)

31 {

32 int i;

33 AVCodecContext *format;

34 int srate_index;

35 int isjointstereo;

37 format = s->streams[0]->codec;

38 /* check for support of the format first */

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 }

47 if (ff_oma_srate_tab[srate_index] * 100 == format->sample_rate)

48 break;

49 }

51 /* Metadata; OpenMG does not support ID3v2.4 */

52 ff_id3v2_write_simple(s, 3, ID3v2_EA3_MAGIC);

54 ffio_wfourcc(s->pb, "EA30円");

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 */

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;

80 case OMA_CODECID_ATRAC3P:

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 */

94 return 0;

95 }

97 AVOutputFormat ff_oma_muxer = {

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 };

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