FFmpeg: libavformat/smjpegenc.c Source File

FFmpeg

[フレーム]

libavformat

smjpegenc.c

Go to the documentation of this file.

1 /*

2 * SMJPEG muxer

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 /**

23 * @file

24 * This is a muxer for Loki SDL Motion JPEG files

25 */

27 #include "avformat.h"

28 #include "internal.h"

29 #include "smjpeg.h"

31 typedef struct SMJPEGMuxContext {

32 uint32_t duration;

33 } SMJPEGMuxContext;

35 static int smjpeg_write_header(AVFormatContext *s)

36 {

37 AVDictionaryEntry *t = NULL;

38 AVIOContext *pb = s->pb;

39 int n, tag;

41 if (s->nb_streams > 2) {

42 av_log(s, AV_LOG_ERROR, "more than >2 streams are not supported\n");

43 return AVERROR(EINVAL);

44 }

45 avio_write(pb, SMJPEG_MAGIC, 8);

46 avio_wb32(pb, 0);

47 avio_wb32(pb, 0);

49 while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {

50 avio_wl32(pb, SMJPEG_TXT);

51 avio_wb32(pb, strlen(t->key) + strlen(t->value) + 3);

52 avio_write(pb, t->key, strlen(t->key));

53 avio_write(pb, " = ", 3);

54 avio_write(pb, t->value, strlen(t->value));

55 }

57 for (n = 0; n < s->nb_streams; n++) {

58 AVStream *st = s->streams[n];

59 AVCodecContext *codec = st->codec;

60 if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {

61 tag = ff_codec_get_tag(ff_codec_smjpeg_audio_tags, codec->codec_id);

62 if (!tag) {

63 av_log(s, AV_LOG_ERROR, "unsupported audio codec\n");

64 return AVERROR(EINVAL);

65 }

66 avio_wl32(pb, SMJPEG_SND);

67 avio_wb32(pb, 8);

68 avio_wb16(pb, codec->sample_rate);

69 avio_w8(pb, codec->bits_per_coded_sample);

70 avio_w8(pb, codec->channels);

71 avio_wl32(pb, tag);

72 avpriv_set_pts_info(st, 32, 1, 1000);

73 } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {

74 tag = ff_codec_get_tag(ff_codec_smjpeg_video_tags, codec->codec_id);

75 if (!tag) {

76 av_log(s, AV_LOG_ERROR, "unsupported video codec\n");

77 return AVERROR(EINVAL);

78 }

79 avio_wl32(pb, SMJPEG_VID);

80 avio_wb32(pb, 12);

81 avio_wb32(pb, 0);

82 avio_wb16(pb, codec->width);

83 avio_wb16(pb, codec->height);

84 avio_wl32(pb, tag);

85 avpriv_set_pts_info(st, 32, 1, 1000);

86 }

87 }

89 avio_wl32(pb, SMJPEG_HEND);

90 avio_flush(pb);

92 return 0;

93 }

95 static int smjpeg_write_packet(AVFormatContext *s, AVPacket *pkt)

96 {

97 SMJPEGMuxContext *smc = s->priv_data;

98 AVIOContext *pb = s->pb;

99 AVStream *st = s->streams[pkt->stream_index];

100 AVCodecContext *codec = st->codec;

101

102 if (codec->codec_type == AVMEDIA_TYPE_AUDIO)

103 avio_wl32(pb, SMJPEG_SNDD);

104 else if (codec->codec_type == AVMEDIA_TYPE_VIDEO)

105 avio_wl32(pb, SMJPEG_VIDD);

106 else

107 return 0;

108

109 avio_wb32(pb, pkt->pts);

110 avio_wb32(pb, pkt->size);

111 avio_write(pb, pkt->data, pkt->size);

112 avio_flush(pb);

113

114 smc->duration = FFMAX(smc->duration, pkt->pts + pkt->duration);

115 return 0;

116 }

117

118 static int smjpeg_write_trailer(AVFormatContext *s)

119 {

120 SMJPEGMuxContext *smc = s->priv_data;

121 AVIOContext *pb = s->pb;

122 int64_t currentpos;

123

124 if (pb->seekable) {

125 currentpos = avio_tell(pb);

126 avio_seek(pb, 12, SEEK_SET);

127 avio_wb32(pb, smc->duration);

128 avio_seek(pb, currentpos, SEEK_SET);

129 }

130

131 avio_wl32(pb, SMJPEG_DONE);

132

133 return 0;

134 }

135

136 AVOutputFormat ff_smjpeg_muxer = {

137 .name = "smjpeg",

138 .long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),

139 .priv_data_size = sizeof(SMJPEGMuxContext),

140 .audio_codec = AV_CODEC_ID_PCM_S16LE,

141 .video_codec = AV_CODEC_ID_MJPEG,

142 .write_header = smjpeg_write_header,

143 .write_packet = smjpeg_write_packet,

144 .write_trailer = smjpeg_write_trailer,

145 .flags = AVFMT_GLOBALHEADER | AVFMT_TS_NONSTRICT,

146 .codec_tag = (const AVCodecTag *const []){ ff_codec_smjpeg_video_tags, ff_codec_smjpeg_audio_tags, 0 },

147 };

Generated on Sat May 25 2013 03:58:49 for FFmpeg by doxygen 1.8.2