FFmpeg: libavformat/ircamdec.c Source File

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libavformat

ircamdec.c

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1 /*

2 * IRCAM demuxer

4 *

5 * This file is part of FFmpeg.

6 *

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.

11 *

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.

16 *

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

20 */

22 #include "libavutil/intreadwrite.h"

23 #include "avformat.h"

24 #include "internal.h"

25 #include "pcm.h"

26 #include "ircam.h"

28 static int ircam_probe(AVProbeData *p)

29 {

30 if ((p->buf[0] == 0x64 && p->buf[1] == 0xA3 && p->buf[3] == 0x00 &&

31 p->buf[2] >= 1 && p->buf[2] <= 4) ||

32 (p->buf[3] == 0x64 && p->buf[2] == 0xA3 && p->buf[0] == 0x00 &&

33 p->buf[1] >= 1 && p->buf[1] <= 3) &&

34 AV_RN32(p->buf + 4) && AV_RN32(p->buf + 8))

35 return AVPROBE_SCORE_MAX / 4 * 3;

36 return 0;

37 }

39 static const struct endianess {

40 uint32_t magic;

41 int is_le;

42 } table[] = {

43 { 0x64A30100, 0 },

44 { 0x64A30200, 1 },

45 { 0x64A30300, 0 },

46 { 0x64A30400, 1 },

47 { 0x0001A364, 1 },

48 { 0x0002A364, 0 },

49 { 0x0003A364, 1 },

50 };

52 static int ircam_read_header(AVFormatContext *s)

53 {

54 uint32_t magic, sample_rate, channels, tag;

55 const AVCodecTag *tags;

56 int le = -1, i;

57 AVStream *st;

59 magic = avio_rl32(s->pb);

60 for (i = 0; i < 7; i++) {

61 if (magic == table[i].magic) {

62 le = table[i].is_le;

63 break;

64 }

65 }

67 if (le == 1) {

68 sample_rate = av_int2float(avio_rl32(s->pb));

69 channels = avio_rl32(s->pb);

70 tag = avio_rl32(s->pb);

71 tags = ff_codec_ircam_le_tags;

72 } else if (le == 0) {

73 sample_rate = av_int2float(avio_rb32(s->pb));

74 channels = avio_rb32(s->pb);

75 tag = avio_rb32(s->pb);

76 tags = ff_codec_ircam_be_tags;

77 } else {

78 return AVERROR_INVALIDDATA;

79 }

81 if (!channels || !sample_rate)

82 return AVERROR_INVALIDDATA;

84 st = avformat_new_stream(s, NULL);

85 if (!st)

86 return AVERROR(ENOMEM);

88 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

89 st->codec->channels = channels;

90 st->codec->sample_rate = sample_rate;

92 st->codec->codec_id = ff_codec_get_id(tags, tag);

93 if (st->codec->codec_id == AV_CODEC_ID_NONE) {

94 av_log(s, AV_LOG_ERROR, "unknown tag %X\n", tag);

95 return AVERROR_INVALIDDATA;

96 }

98 st->codec->bits_per_coded_sample = av_get_bits_per_sample(st->codec->codec_id);

99 st->codec->block_align = st->codec->bits_per_coded_sample * st->codec->channels / 8;

100 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

101 avio_skip(s->pb, 1008);

102

103 return 0;

104 }

105

106 AVInputFormat ff_ircam_demuxer = {

107 .name = "ircam",

108 .long_name = NULL_IF_CONFIG_SMALL("Berkeley/IRCAM/CARL Sound Format"),

109 .read_probe = ircam_probe,

110 .read_header = ircam_read_header,

111 .read_packet = ff_pcm_read_packet,

112 .read_seek = ff_pcm_read_seek,

113 .extensions = "sf,ircam",

114 .flags = AVFMT_GENERIC_INDEX,

115 };

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