FFmpeg: libavformat/epafdec.c Source File

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libavformat

epafdec.c

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1 /*

2 * Ensoniq Paris Audio File 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"

27 static int epaf_probe(AVProbeData *p)

28 {

29 if (((AV_RL32(p->buf) == MKTAG('f','a','p',' ') &&

30 AV_RL32(p->buf + 8) == 1) ||

31 (AV_RL32(p->buf) == MKTAG(' ','p','a','f') &&

32 AV_RN32(p->buf + 8) == 0)) &&

33 !AV_RN32(p->buf + 4) && AV_RN32(p->buf + 12) &&

34 AV_RN32(p->buf + 20))

35 return AVPROBE_SCORE_MAX / 4 * 3;

36 return 0;

37 }

39 static int epaf_read_header(AVFormatContext *s)

40 {

41 int le, sample_rate, codec, channels;

42 AVStream *st;

44 avio_skip(s->pb, 4);

45 if (avio_rl32(s->pb))

46 return AVERROR_INVALIDDATA;

48 le = avio_rl32(s->pb);

49 if (le && le != 1)

50 return AVERROR_INVALIDDATA;

52 if (le) {

53 sample_rate = avio_rl32(s->pb);

54 codec = avio_rl32(s->pb);

55 channels = avio_rl32(s->pb);

56 } else {

57 sample_rate = avio_rb32(s->pb);

58 codec = avio_rb32(s->pb);

59 channels = avio_rb32(s->pb);

60 }

62 if (!channels || !sample_rate)

63 return AVERROR_INVALIDDATA;

65 st = avformat_new_stream(s, NULL);

66 if (!st)

67 return AVERROR(ENOMEM);

69 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

70 st->codec->channels = channels;

71 st->codec->sample_rate = sample_rate;

72 switch (codec) {

73 case 0:

74 st->codec->codec_id = le ? AV_CODEC_ID_PCM_S16LE : AV_CODEC_ID_PCM_S16BE;

75 break;

76 case 2:

77 st->codec->codec_id = AV_CODEC_ID_PCM_S8;

78 break;

79 case 1:

80 avpriv_request_sample(s, "24-bit Paris PCM format");

81 default:

82 return AVERROR_INVALIDDATA;

83 }

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

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

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

90 if (avio_skip(s->pb, 2024) < 0)

91 return AVERROR_INVALIDDATA;

92 return 0;

93 }

95 AVInputFormat ff_epaf_demuxer = {

96 .name = "epaf",

97 .long_name = NULL_IF_CONFIG_SMALL("Ensoniq Paris Audio File"),

98 .read_probe = epaf_probe,

99 .read_header = epaf_read_header,

100 .read_packet = ff_pcm_read_packet,

101 .read_seek = ff_pcm_read_seek,

102 .extensions = "paf,fap",

103 .flags = AVFMT_GENERIC_INDEX,

104 };

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