FFmpeg: libavformat/soxenc.c Source File

FFmpeg

[フレーム]

libavformat

soxenc.c

Go to the documentation of this file.

1 /*

2 * SoX native format muxer

4 *

5 * Based on libSoX sox-fmt.c

7 *

8 * This file is part of FFmpeg.

9 *

10 * FFmpeg is free software; you can redistribute it and/or

11 * modify it under the terms of the GNU Lesser General Public

12 * License as published by the Free Software Foundation; either

13 * version 2.1 of the License, or (at your option) any later version.

14 *

15 * FFmpeg is distributed in the hope that it will be useful,

16 * but WITHOUT ANY WARRANTY; without even the implied warranty of

17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

18 * Lesser General Public License for more details.

19 *

20 * You should have received a copy of the GNU Lesser General Public

21 * License along with FFmpeg; if not, write to the Free Software

22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

23 */

25 /**

26 * @file

27 * SoX native format muxer

28 * @author Daniel Verkamp

29 * @see http://wiki.multimedia.cx/index.php?title=SoX_native_intermediate_format

30 */

32 #include "libavutil/intreadwrite.h"

33 #include "libavutil/intfloat.h"

34 #include "libavutil/dict.h"

35 #include "avformat.h"

36 #include "avio_internal.h"

37 #include "rawenc.h"

38 #include "sox.h"

40 typedef struct {

41 int64_t header_size;

42 } SoXContext;

44 static int sox_write_header(AVFormatContext *s)

45 {

46 SoXContext *sox = s->priv_data;

47 AVIOContext *pb = s->pb;

48 AVCodecContext *enc = s->streams[0]->codec;

49 AVDictionaryEntry *comment;

50 size_t comment_len = 0, comment_size;

52 comment = av_dict_get(s->metadata, "comment", NULL, 0);

53 if (comment)

54 comment_len = strlen(comment->value);

55 comment_size = FFALIGN(comment_len, 8);

57 sox->header_size = SOX_FIXED_HDR + comment_size;

59 if (enc->codec_id == AV_CODEC_ID_PCM_S32LE) {

60 ffio_wfourcc(pb, ".SoX");

61 avio_wl32(pb, sox->header_size);

62 avio_wl64(pb, 0); /* number of samples */

63 avio_wl64(pb, av_double2int(enc->sample_rate));

64 avio_wl32(pb, enc->channels);

65 avio_wl32(pb, comment_size);

66 } else if (enc->codec_id == AV_CODEC_ID_PCM_S32BE) {

67 ffio_wfourcc(pb, "XoS.");

68 avio_wb32(pb, sox->header_size);

69 avio_wb64(pb, 0); /* number of samples */

70 avio_wb64(pb, av_double2int(enc->sample_rate));

71 avio_wb32(pb, enc->channels);

72 avio_wb32(pb, comment_size);

73 } else {

74 av_log(s, AV_LOG_ERROR, "invalid codec; use pcm_s32le or pcm_s32be\n");

75 return -1;

76 }

78 if (comment_len)

79 avio_write(pb, comment->value, comment_len);

81 ffio_fill(pb, 0, comment_size - comment_len);

83 avio_flush(pb);

85 return 0;

86 }

88 static int sox_write_trailer(AVFormatContext *s)

89 {

90 SoXContext *sox = s->priv_data;

91 AVIOContext *pb = s->pb;

92 AVCodecContext *enc = s->streams[0]->codec;

94 if (s->pb->seekable) {

95 /* update number of samples */

96 int64_t file_size = avio_tell(pb);

97 int64_t num_samples = (file_size - sox->header_size - 4LL) >> 2LL;

98 avio_seek(pb, 8, SEEK_SET);

99 if (enc->codec_id == AV_CODEC_ID_PCM_S32LE) {

100 avio_wl64(pb, num_samples);

101 } else

102 avio_wb64(pb, num_samples);

103 avio_seek(pb, file_size, SEEK_SET);

104

105 avio_flush(pb);

106 }

107

108 return 0;

109 }

110

111 AVOutputFormat ff_sox_muxer = {

112 .name = "sox",

113 .long_name = NULL_IF_CONFIG_SMALL("SoX native"),

114 .extensions = "sox",

115 .priv_data_size = sizeof(SoXContext),

116 .audio_codec = AV_CODEC_ID_PCM_S32LE,

117 .video_codec = AV_CODEC_ID_NONE,

118 .write_header = sox_write_header,

119 .write_packet = ff_raw_write_packet,

120 .write_trailer = sox_write_trailer,

121 };

Generated on Wed Jul 10 2013 23:48:14 for FFmpeg by doxygen 1.8.2