FFmpeg: libavformat/dsicin.c Source File

FFmpeg

[フレーム]

libavformat

dsicin.c

Go to the documentation of this file.

1 /*

2 * Delphine Software International CIN 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 /**

23 * @file

24 * Delphine Software International CIN file demuxer

25 */

27 #include "libavutil/channel_layout.h"

28 #include "libavutil/intreadwrite.h"

29 #include "avformat.h"

30 #include "internal.h"

31 #include "avio_internal.h"

34 typedef struct CinFileHeader {

35 int video_frame_size;

36 int video_frame_width;

37 int video_frame_height;

38 int audio_frequency;

39 int audio_bits;

40 int audio_stereo;

41 int audio_frame_size;

42 } CinFileHeader;

44 typedef struct CinFrameHeader {

45 int audio_frame_type;

46 int video_frame_type;

47 int pal_colors_count;

48 int audio_frame_size;

49 int video_frame_size;

50 } CinFrameHeader;

52 typedef struct CinDemuxContext {

53 int audio_stream_index;

54 int video_stream_index;

55 CinFileHeader file_header;

56 int64_t audio_stream_pts;

57 int64_t video_stream_pts;

58 CinFrameHeader frame_header;

59 int audio_buffer_size;

60 } CinDemuxContext;

63 static int cin_probe(AVProbeData *p)

64 {

65 /* header starts with this special marker */

66 if (AV_RL32(&p->buf[0]) != 0x55AA0000)

67 return 0;

69 /* for accuracy, check some header field values */

70 if (AV_RL32(&p->buf[12]) != 22050 || p->buf[16] != 16 || p->buf[17] != 0)

71 return 0;

73 return AVPROBE_SCORE_MAX;

74 }

76 static int cin_read_file_header(CinDemuxContext *cin, AVIOContext *pb) {

77 CinFileHeader *hdr = &cin->file_header;

79 if (avio_rl32(pb) != 0x55AA0000)

80 return AVERROR_INVALIDDATA;

82 hdr->video_frame_size = avio_rl32(pb);

83 hdr->video_frame_width = avio_rl16(pb);

84 hdr->video_frame_height = avio_rl16(pb);

85 hdr->audio_frequency = avio_rl32(pb);

86 hdr->audio_bits = avio_r8(pb);

87 hdr->audio_stereo = avio_r8(pb);

88 hdr->audio_frame_size = avio_rl16(pb);

90 if (hdr->audio_frequency != 22050 || hdr->audio_bits != 16 || hdr->audio_stereo != 0)

91 return AVERROR_INVALIDDATA;

93 return 0;

94 }

96 static int cin_read_header(AVFormatContext *s)

97 {

98 int rc;

99 CinDemuxContext *cin = s->priv_data;

100 CinFileHeader *hdr = &cin->file_header;

101 AVIOContext *pb = s->pb;

102 AVStream *st;

103

104 rc = cin_read_file_header(cin, pb);

105 if (rc)

106 return rc;

107

108 cin->video_stream_pts = 0;

109 cin->audio_stream_pts = 0;

110 cin->audio_buffer_size = 0;

111

112 /* initialize the video decoder stream */

113 st = avformat_new_stream(s, NULL);

114 if (!st)

115 return AVERROR(ENOMEM);

116

117 avpriv_set_pts_info(st, 32, 1, 12);

118 cin->video_stream_index = st->index;

119 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

120 st->codec->codec_id = AV_CODEC_ID_DSICINVIDEO;

121 st->codec->codec_tag = 0; /* no fourcc */

122 st->codec->width = hdr->video_frame_width;

123 st->codec->height = hdr->video_frame_height;

124

125 /* initialize the audio decoder stream */

126 st = avformat_new_stream(s, NULL);

127 if (!st)

128 return AVERROR(ENOMEM);

129

130 avpriv_set_pts_info(st, 32, 1, 22050);

131 cin->audio_stream_index = st->index;

132 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

133 st->codec->codec_id = AV_CODEC_ID_DSICINAUDIO;

134 st->codec->codec_tag = 0; /* no tag */

135 st->codec->channels = 1;

136 st->codec->channel_layout = AV_CH_LAYOUT_MONO;

137 st->codec->sample_rate = 22050;

138 st->codec->bits_per_coded_sample = 8;

139 st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;

140

141 return 0;

142 }

143

144 static int cin_read_frame_header(CinDemuxContext *cin, AVIOContext *pb) {

145 CinFrameHeader *hdr = &cin->frame_header;

146

147 hdr->video_frame_type = avio_r8(pb);

148 hdr->audio_frame_type = avio_r8(pb);

149 hdr->pal_colors_count = avio_rl16(pb);

150 hdr->video_frame_size = avio_rl32(pb);

151 hdr->audio_frame_size = avio_rl32(pb);

152

153 if (url_feof(pb) || pb->error)

154 return AVERROR(EIO);

155

156 if (avio_rl32(pb) != 0xAA55AA55)

157 return AVERROR_INVALIDDATA;

158

159 return 0;

160 }

161

162 static int cin_read_packet(AVFormatContext *s, AVPacket *pkt)

163 {

164 CinDemuxContext *cin = s->priv_data;

165 AVIOContext *pb = s->pb;

166 CinFrameHeader *hdr = &cin->frame_header;

167 int rc, palette_type, pkt_size;

168 int ret;

169

170 if (cin->audio_buffer_size == 0) {

171 rc = cin_read_frame_header(cin, pb);

172 if (rc)

173 return rc;

174

175 if ((int16_t)hdr->pal_colors_count < 0) {

176 hdr->pal_colors_count = -(int16_t)hdr->pal_colors_count;

177 palette_type = 1;

178 } else {

179 palette_type = 0;

180 }

181

182 /* palette and video packet */

183 pkt_size = (palette_type + 3) * hdr->pal_colors_count + hdr->video_frame_size;

184

185 pkt_size = ffio_limit(pb, pkt_size);

186

187 ret = av_new_packet(pkt, 4 + pkt_size);

188 if (ret < 0)

189 return ret;

190

191 pkt->stream_index = cin->video_stream_index;

192 pkt->pts = cin->video_stream_pts++;

193

194 pkt->data[0] = palette_type;

195 pkt->data[1] = hdr->pal_colors_count & 0xFF;

196 pkt->data[2] = hdr->pal_colors_count >> 8;

197 pkt->data[3] = hdr->video_frame_type;

198

199 ret = avio_read(pb, &pkt->data[4], pkt_size);

200 if (ret < 0) {

201 av_free_packet(pkt);

202 return ret;

203 }

204 if (ret < pkt_size)

205 av_shrink_packet(pkt, 4 + ret);

206

207 /* sound buffer will be processed on next read_packet() call */

208 cin->audio_buffer_size = hdr->audio_frame_size;

209 return 0;

210 }

211

212 /* audio packet */

213 ret = av_get_packet(pb, pkt, cin->audio_buffer_size);

214 if (ret < 0)

215 return ret;

216

217 pkt->stream_index = cin->audio_stream_index;

218 pkt->pts = cin->audio_stream_pts;

219 pkt->duration = cin->audio_buffer_size - (pkt->pts == 0);

220 cin->audio_stream_pts += pkt->duration;

221 cin->audio_buffer_size = 0;

222 return 0;

223 }

224

225 AVInputFormat ff_dsicin_demuxer = {

226 .name = "dsicin",

227 .long_name = NULL_IF_CONFIG_SMALL("Delphine Software International CIN"),

228 .priv_data_size = sizeof(CinDemuxContext),

229 .read_probe = cin_probe,

230 .read_header = cin_read_header,

231 .read_packet = cin_read_packet,

232 };

Generated on Wed Jul 10 2013 23:48:11 for FFmpeg by doxygen 1.8.2