FFmpeg: libavformat/sierravmd.c Source File

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libavformat

sierravmd.c

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1 /*

2 * Sierra VMD Format 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 * Sierra VMD file demuxer

25 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)

26 * for more information on the Sierra VMD file format, visit:

27 * http://www.pcisys.net/~melanson/codecs/

28 */

30 #include "libavutil/channel_layout.h"

31 #include "libavutil/intreadwrite.h"

32 #include "avformat.h"

33 #include "internal.h"

34 #include "avio_internal.h"

36 #define VMD_HEADER_SIZE 0x0330

37 #define BYTES_PER_FRAME_RECORD 16

39 typedef struct {

40 int stream_index;

41 int64_t frame_offset;

42 unsigned int frame_size;

43 int64_t pts;

44 int keyframe;

45 unsigned char frame_record[BYTES_PER_FRAME_RECORD];

46 } vmd_frame;

48 typedef struct VmdDemuxContext {

49 int video_stream_index;

50 int audio_stream_index;

52 unsigned int frame_count;

53 unsigned int frames_per_block;

54 vmd_frame *frame_table;

55 unsigned int current_frame;

56 int is_indeo3;

58 int sample_rate;

59 int64_t audio_sample_counter;

60 int skiphdr;

62 unsigned char vmd_header[VMD_HEADER_SIZE];

63 } VmdDemuxContext;

65 static int vmd_probe(AVProbeData *p)

66 {

67 int w, h;

68 if (p->buf_size < 16)

69 return 0;

70 /* check if the first 2 bytes of the file contain the appropriate size

71 * of a VMD header chunk */

72 if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)

73 return 0;

74 w = AV_RL16(&p->buf[12]);

75 h = AV_RL16(&p->buf[14]);

76 if (!w || w > 2048 || !h || h > 2048)

77 return 0;

79 /* only return half certainty since this check is a bit sketchy */

80 return AVPROBE_SCORE_MAX / 2;

81 }

83 static int vmd_read_header(AVFormatContext *s)

84 {

85 VmdDemuxContext *vmd = s->priv_data;

86 AVIOContext *pb = s->pb;

87 AVStream *st = NULL, *vst;

88 unsigned int toc_offset;

89 unsigned char *raw_frame_table;

90 int raw_frame_table_size;

91 int64_t current_offset;

92 int i, j;

93 unsigned int total_frames;

94 int64_t current_audio_pts = 0;

95 unsigned char chunk[BYTES_PER_FRAME_RECORD];

96 int num, den;

97 int sound_buffers;

99 /* fetch the main header, including the 2 header length bytes */

100 avio_seek(pb, 0, SEEK_SET);

101 if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)

102 return AVERROR(EIO);

103

104 if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')

105 vmd->is_indeo3 = 1;

106 else

107 vmd->is_indeo3 = 0;

108 /* start up the decoders */

109 vst = avformat_new_stream(s, NULL);

110 if (!vst)

111 return AVERROR(ENOMEM);

112 avpriv_set_pts_info(vst, 33, 1, 10);

113 vmd->video_stream_index = vst->index;

114 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

115 vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;

116 vst->codec->codec_tag = 0; /* no fourcc */

117 vst->codec->width = AV_RL16(&vmd->vmd_header[12]);

118 vst->codec->height = AV_RL16(&vmd->vmd_header[14]);

119 if(vmd->is_indeo3 && vst->codec->width > 320){

120 vst->codec->width >>= 1;

121 vst->codec->height >>= 1;

122 }

123 vst->codec->extradata_size = VMD_HEADER_SIZE;

124 vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);

125 memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);

126

127 /* if sample rate is 0, assume no audio */

128 vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);

129 if (vmd->sample_rate) {

130 st = avformat_new_stream(s, NULL);

131 if (!st)

132 return AVERROR(ENOMEM);

133 vmd->audio_stream_index = st->index;

134 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

135 st->codec->codec_id = AV_CODEC_ID_VMDAUDIO;

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

137 if (vmd->vmd_header[811] & 0x80) {

138 st->codec->channels = 2;

139 st->codec->channel_layout = AV_CH_LAYOUT_STEREO;

140 } else {

141 st->codec->channels = 1;

142 st->codec->channel_layout = AV_CH_LAYOUT_MONO;

143 }

144 st->codec->sample_rate = vmd->sample_rate;

145 st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);

146 if (st->codec->block_align & 0x8000) {

147 st->codec->bits_per_coded_sample = 16;

148 st->codec->block_align = -(st->codec->block_align - 0x10000);

149 } else {

150 st->codec->bits_per_coded_sample = 8;

151 }

152 st->codec->bit_rate = st->codec->sample_rate *

153 st->codec->bits_per_coded_sample * st->codec->channels;

154

155 /* calculate pts */

156 num = st->codec->block_align;

157 den = st->codec->sample_rate * st->codec->channels;

158 av_reduce(&num, &den, num, den, (1UL<<31)-1);

159 avpriv_set_pts_info(vst, 33, num, den);

160 avpriv_set_pts_info(st, 33, num, den);

161 }

162

163 toc_offset = AV_RL32(&vmd->vmd_header[812]);

164 vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);

165 vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);

166 avio_seek(pb, toc_offset, SEEK_SET);

167

168 raw_frame_table = NULL;

169 vmd->frame_table = NULL;

170 sound_buffers = AV_RL16(&vmd->vmd_header[808]);

171 raw_frame_table_size = vmd->frame_count * 6;

172 if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){

173 av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");

174 return -1;

175 }

176 raw_frame_table = av_malloc(raw_frame_table_size);

177 vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));

178 if (!raw_frame_table || !vmd->frame_table) {

179 av_free(raw_frame_table);

180 av_free(vmd->frame_table);

181 return AVERROR(ENOMEM);

182 }

183 if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=

184 raw_frame_table_size) {

185 av_free(raw_frame_table);

186 av_free(vmd->frame_table);

187 return AVERROR(EIO);

188 }

189

190 total_frames = 0;

191 for (i = 0; i < vmd->frame_count; i++) {

192

193 current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);

194

195 /* handle each entry in index block */

196 for (j = 0; j < vmd->frames_per_block; j++) {

197 int type;

198 uint32_t size;

199

200 avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);

201 type = chunk[0];

202 size = AV_RL32(&chunk[2]);

203 if(!size && type != 1)

204 continue;

205 switch(type) {

206 case 1: /* Audio Chunk */

207 if (!st) break;

208 /* first audio chunk contains several audio buffers */

209 vmd->frame_table[total_frames].frame_offset = current_offset;

210 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;

211 vmd->frame_table[total_frames].frame_size = size;

212 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);

213 vmd->frame_table[total_frames].pts = current_audio_pts;

214 total_frames++;

215 if(!current_audio_pts)

216 current_audio_pts += sound_buffers - 1;

217 else

218 current_audio_pts++;

219 break;

220 case 2: /* Video Chunk */

221 vmd->frame_table[total_frames].frame_offset = current_offset;

222 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;

223 vmd->frame_table[total_frames].frame_size = size;

224 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);

225 vmd->frame_table[total_frames].pts = i;

226 total_frames++;

227 break;

228 }

229 current_offset += size;

230 }

231 }

232

233 av_free(raw_frame_table);

234

235 vmd->current_frame = 0;

236 vmd->frame_count = total_frames;

237

238 return 0;

239 }

240

241 static int vmd_read_packet(AVFormatContext *s,

242 AVPacket *pkt)

243 {

244 VmdDemuxContext *vmd = s->priv_data;

245 AVIOContext *pb = s->pb;

246 int ret = 0;

247 vmd_frame *frame;

248

249 if (vmd->current_frame >= vmd->frame_count)

250 return AVERROR_EOF;

251

252 frame = &vmd->frame_table[vmd->current_frame];

253 /* position the stream (will probably be there already) */

254 avio_seek(pb, frame->frame_offset, SEEK_SET);

255

256 if(ffio_limit(pb, frame->frame_size) != frame->frame_size)

257 return AVERROR(EIO);

258 if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))

259 return AVERROR(ENOMEM);

260 pkt->pos= avio_tell(pb);

261 memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);

262 if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)

263 ret = avio_read(pb, pkt->data, frame->frame_size);

264 else

265 ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,

266 frame->frame_size);

267

268 if (ret != frame->frame_size) {

269 av_free_packet(pkt);

270 ret = AVERROR(EIO);

271 }

272 pkt->stream_index = frame->stream_index;

273 pkt->pts = frame->pts;

274 av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",

275 (frame->frame_record[0] == 0x02) ? "video" : "audio",

276 frame->frame_size + BYTES_PER_FRAME_RECORD,

277 pkt->pts);

278

279 vmd->current_frame++;

280

281 return ret;

282 }

283

284 static int vmd_read_close(AVFormatContext *s)

285 {

286 VmdDemuxContext *vmd = s->priv_data;

287

288 av_free(vmd->frame_table);

289

290 return 0;

291 }

292

293 AVInputFormat ff_vmd_demuxer = {

294 .name = "vmd",

295 .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD"),

296 .priv_data_size = sizeof(VmdDemuxContext),

297 .read_probe = vmd_probe,

298 .read_header = vmd_read_header,

299 .read_packet = vmd_read_packet,

300 .read_close = vmd_read_close,

301 };

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