FFmpeg: libavformat/nuv.c Source File

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libavformat

nuv.c

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1 /*

2 * NuppelVideo 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/channel_layout.h"

23 #include "libavutil/intreadwrite.h"

24 #include "libavutil/intfloat.h"

25 #include "avformat.h"

26 #include "internal.h"

27 #include "riff.h"

29 static const AVCodecTag nuv_audio_tags[] = {

30 { AV_CODEC_ID_PCM_S16LE, MKTAG('R', 'A', 'W', 'A') },

31 { AV_CODEC_ID_MP3, MKTAG('L', 'A', 'M', 'E') },

32 { AV_CODEC_ID_NONE, 0 },

33 };

35 typedef struct {

36 int v_id;

37 int a_id;

38 int rtjpg_video;

39 } NUVContext;

41 typedef enum {

42 NUV_VIDEO = 'V',

43 NUV_EXTRADATA = 'D',

44 NUV_AUDIO = 'A',

45 NUV_SEEKP = 'R',

46 NUV_MYTHEXT = 'X'

47 } nuv_frametype;

49 static int nuv_probe(AVProbeData *p)

50 {

51 if (!memcmp(p->buf, "NuppelVideo", 12))

52 return AVPROBE_SCORE_MAX;

53 if (!memcmp(p->buf, "MythTVVideo", 12))

54 return AVPROBE_SCORE_MAX;

55 return 0;

56 }

58 /// little macro to sanitize packet size

59 #define PKTSIZE(s) (s & 0xffffff)

61 /**

62 * @brief read until we found all data needed for decoding

63 * @param vst video stream of which to change parameters

64 * @param ast video stream of which to change parameters

65 * @param myth set if this is a MythTVVideo format file

66 * @return 0 or AVERROR code

67 */

68 static int get_codec_data(AVIOContext *pb, AVStream *vst,

69 AVStream *ast, int myth)

70 {

71 nuv_frametype frametype;

73 if (!vst && !myth)

74 return 1; // no codec data needed

75 while (!url_feof(pb)) {

76 int size, subtype;

78 frametype = avio_r8(pb);

79 switch (frametype) {

80 case NUV_EXTRADATA:

81 subtype = avio_r8(pb);

82 avio_skip(pb, 6);

83 size = PKTSIZE(avio_rl32(pb));

84 if (vst && subtype == 'R') {

85 if (vst->codec->extradata) {

86 av_freep(&vst->codec->extradata);

87 vst->codec->extradata_size = 0;

88 }

89 if (ff_alloc_extradata(vst->codec, size))

90 return AVERROR(ENOMEM);

91 avio_read(pb, vst->codec->extradata, size);

92 size = 0;

93 if (!myth)

94 return 0;

95 }

96 break;

97 case NUV_MYTHEXT:

98 avio_skip(pb, 7);

99 size = PKTSIZE(avio_rl32(pb));

100 if (size != 128 * 4)

101 break;

102 avio_rl32(pb); // version

103 if (vst) {

104 vst->codec->codec_tag = avio_rl32(pb);

105 vst->codec->codec_id =

106 ff_codec_get_id(ff_codec_bmp_tags, vst->codec->codec_tag);

107 if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))

108 vst->codec->codec_id = AV_CODEC_ID_NUV;

109 } else

110 avio_skip(pb, 4);

111

112 if (ast) {

113 int id;

114

115 ast->codec->codec_tag = avio_rl32(pb);

116 ast->codec->sample_rate = avio_rl32(pb);

117 ast->codec->bits_per_coded_sample = avio_rl32(pb);

118 ast->codec->channels = avio_rl32(pb);

119 ast->codec->channel_layout = 0;

120

121 id = ff_wav_codec_get_id(ast->codec->codec_tag,

122 ast->codec->bits_per_coded_sample);

123 if (id == AV_CODEC_ID_NONE) {

124 id = ff_codec_get_id(nuv_audio_tags, ast->codec->codec_tag);

125 if (id == AV_CODEC_ID_PCM_S16LE)

126 id = ff_get_pcm_codec_id(ast->codec->bits_per_coded_sample,

127 0, 0, ~1);

128 }

129 ast->codec->codec_id = id;

130

131 ast->need_parsing = AVSTREAM_PARSE_FULL;

132 } else

133 avio_skip(pb, 4 * 4);

134

135 size -= 6 * 4;

136 avio_skip(pb, size);

137 return 0;

138 case NUV_SEEKP:

139 size = 11;

140 break;

141 default:

142 avio_skip(pb, 7);

143 size = PKTSIZE(avio_rl32(pb));

144 break;

145 }

146 avio_skip(pb, size);

147 }

148

149 return 0;

150 }

151

152 static int nuv_header(AVFormatContext *s)

153 {

154 NUVContext *ctx = s->priv_data;

155 AVIOContext *pb = s->pb;

156 char id_string[12];

157 double aspect, fps;

158 int is_mythtv, width, height, v_packs, a_packs, ret;

159 AVStream *vst = NULL, *ast = NULL;

160

161 avio_read(pb, id_string, 12);

162 is_mythtv = !memcmp(id_string, "MythTVVideo", 12);

163 avio_skip(pb, 5); // version string

164 avio_skip(pb, 3); // padding

165 width = avio_rl32(pb);

166 height = avio_rl32(pb);

167 avio_rl32(pb); // unused, "desiredwidth"

168 avio_rl32(pb); // unused, "desiredheight"

169 avio_r8(pb); // 'P' == progressive, 'I' == interlaced

170 avio_skip(pb, 3); // padding

171 aspect = av_int2double(avio_rl64(pb));

172 if (aspect > 0.9999 && aspect < 1.0001)

173 aspect = 4.0 / 3.0;

174 fps = av_int2double(avio_rl64(pb));

175

176 // number of packets per stream type, -1 means unknown, e.g. streaming

177 v_packs = avio_rl32(pb);

178 a_packs = avio_rl32(pb);

179 avio_rl32(pb); // text

180

181 avio_rl32(pb); // keyframe distance (?)

182

183 if (v_packs) {

184 vst = avformat_new_stream(s, NULL);

185 if (!vst)

186 return AVERROR(ENOMEM);

187 ctx->v_id = vst->index;

188

189 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

190 vst->codec->codec_id = AV_CODEC_ID_NUV;

191 vst->codec->width = width;

192 vst->codec->height = height;

193 vst->codec->bits_per_coded_sample = 10;

194 vst->sample_aspect_ratio = av_d2q(aspect * height / width,

195 10000);

196 #if FF_API_R_FRAME_RATE

197 vst->r_frame_rate =

198 #endif

199 vst->avg_frame_rate = av_d2q(fps, 60000);

200 avpriv_set_pts_info(vst, 32, 1, 1000);

201 } else

202 ctx->v_id = -1;

203

204 if (a_packs) {

205 ast = avformat_new_stream(s, NULL);

206 if (!ast)

207 return AVERROR(ENOMEM);

208 ctx->a_id = ast->index;

209

210 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

211 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

212 ast->codec->channels = 2;

213 ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;

214 ast->codec->sample_rate = 44100;

215 ast->codec->bit_rate = 2 * 2 * 44100 * 8;

216 ast->codec->block_align = 2 * 2;

217 ast->codec->bits_per_coded_sample = 16;

218 avpriv_set_pts_info(ast, 32, 1, 1000);

219 } else

220 ctx->a_id = -1;

221

222 if ((ret = get_codec_data(pb, vst, ast, is_mythtv)) < 0)

223 return ret;

224

225 ctx->rtjpg_video = vst && vst->codec->codec_id == AV_CODEC_ID_NUV;

226

227 return 0;

228 }

229

230 #define HDRSIZE 12

231

232 static int nuv_packet(AVFormatContext *s, AVPacket *pkt)

233 {

234 NUVContext *ctx = s->priv_data;

235 AVIOContext *pb = s->pb;

236 uint8_t hdr[HDRSIZE];

237 nuv_frametype frametype;

238 int ret, size;

239

240 while (!url_feof(pb)) {

241 int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;

242 uint64_t pos = avio_tell(pb);

243

244 ret = avio_read(pb, hdr, HDRSIZE);

245 if (ret < HDRSIZE)

246 return ret < 0 ? ret : AVERROR(EIO);

247

248 frametype = hdr[0];

249 size = PKTSIZE(AV_RL32(&hdr[8]));

250

251 switch (frametype) {

252 case NUV_EXTRADATA:

253 if (!ctx->rtjpg_video) {

254 avio_skip(pb, size);

255 break;

256 }

257 case NUV_VIDEO:

258 if (ctx->v_id < 0) {

259 av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");

260 avio_skip(pb, size);

261 break;

262 }

263 ret = av_new_packet(pkt, copyhdrsize + size);

264 if (ret < 0)

265 return ret;

266

267 pkt->pos = pos;

268 pkt->flags |= hdr[2] == 0 ? AV_PKT_FLAG_KEY : 0;

269 pkt->pts = AV_RL32(&hdr[4]);

270 pkt->stream_index = ctx->v_id;

271 memcpy(pkt->data, hdr, copyhdrsize);

272 ret = avio_read(pb, pkt->data + copyhdrsize, size);

273 if (ret < 0) {

274 av_free_packet(pkt);

275 return ret;

276 }

277 if (ret < size)

278 av_shrink_packet(pkt, copyhdrsize + ret);

279 return 0;

280 case NUV_AUDIO:

281 if (ctx->a_id < 0) {

282 av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");

283 avio_skip(pb, size);

284 break;

285 }

286 ret = av_get_packet(pb, pkt, size);

287 pkt->flags |= AV_PKT_FLAG_KEY;

288 pkt->pos = pos;

289 pkt->pts = AV_RL32(&hdr[4]);

290 pkt->stream_index = ctx->a_id;

291 if (ret < 0)

292 return ret;

293 return 0;

294 case NUV_SEEKP:

295 // contains no data, size value is invalid

296 break;

297 default:

298 avio_skip(pb, size);

299 break;

300 }

301 }

302

303 return AVERROR(EIO);

304 }

305

306 /**

307 * \brief looks for the string RTjjjjjjjjjj in the stream too resync reading

308 * \return 1 if the syncword is found 0 otherwise.

309 */

310 static int nuv_resync(AVFormatContext *s, int64_t pos_limit) {

311 AVIOContext *pb = s->pb;

312 uint32_t tag = 0;

313 while(!url_feof(pb) && avio_tell(pb) < pos_limit) {

314 tag = (tag << 8) | avio_r8(pb);

315 if (tag == MKBETAG('R','T','j','j') &&

316 (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j') &&

317 (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j'))

318 return 1;

319 }

320 return 0;

321 }

322

323 /**

324 * \brief attempts to read a timestamp from stream at the given stream position

325 * \return timestamp if successful and AV_NOPTS_VALUE if failure

326 */

327 static int64_t nuv_read_dts(AVFormatContext *s, int stream_index,

328 int64_t *ppos, int64_t pos_limit)

329 {

330 NUVContext *ctx = s->priv_data;

331 AVIOContext *pb = s->pb;

332 uint8_t hdr[HDRSIZE];

333 nuv_frametype frametype;

334 int size, key, idx;

335 int64_t pos, dts;

336

337 if (avio_seek(pb, *ppos, SEEK_SET) < 0)

338 return AV_NOPTS_VALUE;

339

340 if (!nuv_resync(s, pos_limit))

341 return AV_NOPTS_VALUE;

342

343 while (!url_feof(pb) && avio_tell(pb) < pos_limit) {

344 if (avio_read(pb, hdr, HDRSIZE) < HDRSIZE)

345 return AV_NOPTS_VALUE;

346 frametype = hdr[0];

347 size = PKTSIZE(AV_RL32(&hdr[8]));

348 switch (frametype) {

349 case NUV_SEEKP:

350 break;

351 case NUV_AUDIO:

352 case NUV_VIDEO:

353 if (frametype == NUV_VIDEO) {

354 idx = ctx->v_id;

355 key = hdr[2] == 0;

356 } else {

357 idx = ctx->a_id;

358 key = 1;

359 }

360 if (stream_index == idx) {

361

362 pos = avio_tell(s->pb) - HDRSIZE;

363 dts = AV_RL32(&hdr[4]);

364

365 // TODO - add general support in av_gen_search, so it adds positions after reading timestamps

366 av_add_index_entry(s->streams[stream_index], pos, dts, size + HDRSIZE, 0,

367 key ? AVINDEX_KEYFRAME : 0);

368

369 *ppos = pos;

370 return dts;

371 }

372 default:

373 avio_skip(pb, size);

374 break;

375 }

376 }

377 return AV_NOPTS_VALUE;

378 }

379

380

381 AVInputFormat ff_nuv_demuxer = {

382 .name = "nuv",

383 .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo"),

384 .priv_data_size = sizeof(NUVContext),

385 .read_probe = nuv_probe,

386 .read_header = nuv_header,

387 .read_packet = nuv_packet,

388 .read_timestamp = nuv_read_dts,

389 .flags = AVFMT_GENERIC_INDEX,

390 };

Generated on Sat Jan 25 2014 19:51:52 for FFmpeg by doxygen 1.8.2