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_get_extradata(vst->codec, pb, size) < 0)

90 return AVERROR(ENOMEM);

91 size = 0;

92 if (!myth)

93 return 0;

94 }

95 break;

96 case NUV_MYTHEXT:

97 avio_skip(pb, 7);

98 size = PKTSIZE(avio_rl32(pb));

99 if (size != 128 * 4)

100 break;

101 avio_rl32(pb); // version

102 if (vst) {

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

104 vst->codec->codec_id =

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

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

107 vst->codec->codec_id = AV_CODEC_ID_NUV;

108 } else

109 avio_skip(pb, 4);

110

111 if (ast) {

112 int id;

113

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

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

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

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

118 ast->codec->channel_layout = 0;

119

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

121 ast->codec->bits_per_coded_sample);

122 if (id == AV_CODEC_ID_NONE) {

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

124 if (id == AV_CODEC_ID_PCM_S16LE)

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

126 0, 0, ~1);

127 }

128 ast->codec->codec_id = id;

129

130 ast->need_parsing = AVSTREAM_PARSE_FULL;

131 } else

132 avio_skip(pb, 4 * 4);

133

134 size -= 6 * 4;

135 avio_skip(pb, size);

136 return 0;

137 case NUV_SEEKP:

138 size = 11;

139 break;

140 default:

141 avio_skip(pb, 7);

142 size = PKTSIZE(avio_rl32(pb));

143 break;

144 }

145 avio_skip(pb, size);

146 }

147

148 return 0;

149 }

150

151 static int nuv_header(AVFormatContext *s)

152 {

153 NUVContext *ctx = s->priv_data;

154 AVIOContext *pb = s->pb;

155 char id_string[12];

156 double aspect, fps;

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

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

159

160 avio_read(pb, id_string, 12);

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

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

163 avio_skip(pb, 3); // padding

164 width = avio_rl32(pb);

165 height = avio_rl32(pb);

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

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

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

169 avio_skip(pb, 3); // padding

170 aspect = av_int2double(avio_rl64(pb));

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

172 aspect = 4.0 / 3.0;

173 fps = av_int2double(avio_rl64(pb));

174

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

176 v_packs = avio_rl32(pb);

177 a_packs = avio_rl32(pb);

178 avio_rl32(pb); // text

179

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

181

182 if (v_packs) {

183 vst = avformat_new_stream(s, NULL);

184 if (!vst)

185 return AVERROR(ENOMEM);

186 ctx->v_id = vst->index;

187

188 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

189 vst->codec->codec_id = AV_CODEC_ID_NUV;

190 vst->codec->width = width;

191 vst->codec->height = height;

192 vst->codec->bits_per_coded_sample = 10;

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

194 10000);

195 #if FF_API_R_FRAME_RATE

196 vst->r_frame_rate =

197 #endif

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

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

200 } else

201 ctx->v_id = -1;

202

203 if (a_packs) {

204 ast = avformat_new_stream(s, NULL);

205 if (!ast)

206 return AVERROR(ENOMEM);

207 ctx->a_id = ast->index;

208

209 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

210 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

211 ast->codec->channels = 2;

212 ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;

213 ast->codec->sample_rate = 44100;

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

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

216 ast->codec->bits_per_coded_sample = 16;

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

218 } else

219 ctx->a_id = -1;

220

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

222 return ret;

223

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

225

226 return 0;

227 }

228

229 #define HDRSIZE 12

230

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

232 {

233 NUVContext *ctx = s->priv_data;

234 AVIOContext *pb = s->pb;

235 uint8_t hdr[HDRSIZE];

236 nuv_frametype frametype;

237 int ret, size;

238

239 while (!url_feof(pb)) {

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

241 uint64_t pos = avio_tell(pb);

242

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

244 if (ret < HDRSIZE)

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

246

247 frametype = hdr[0];

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

249

250 switch (frametype) {

251 case NUV_EXTRADATA:

252 if (!ctx->rtjpg_video) {

253 avio_skip(pb, size);

254 break;

255 }

256 case NUV_VIDEO:

257 if (ctx->v_id < 0) {

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

259 avio_skip(pb, size);

260 break;

261 }

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

263 if (ret < 0)

264 return ret;

265

266 pkt->pos = pos;

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

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

269 pkt->stream_index = ctx->v_id;

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

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

272 if (ret < 0) {

273 av_free_packet(pkt);

274 return ret;

275 }

276 if (ret < size)

277 av_shrink_packet(pkt, copyhdrsize + ret);

278 return 0;

279 case NUV_AUDIO:

280 if (ctx->a_id < 0) {

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

282 avio_skip(pb, size);

283 break;

284 }

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

286 pkt->flags |= AV_PKT_FLAG_KEY;

287 pkt->pos = pos;

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

289 pkt->stream_index = ctx->a_id;

290 if (ret < 0)

291 return ret;

292 return 0;

293 case NUV_SEEKP:

294 // contains no data, size value is invalid

295 break;

296 default:

297 avio_skip(pb, size);

298 break;

299 }

300 }

301

302 return AVERROR(EIO);

303 }

304

305 /**

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

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

308 */

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

310 AVIOContext *pb = s->pb;

311 uint32_t tag = 0;

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

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

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

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

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

317 return 1;

318 }

319 return 0;

320 }

321

322 /**

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

324 * \return timestamp if successful and AV_NOPTS_VALUE if failure

325 */

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

327 int64_t *ppos, int64_t pos_limit)

328 {

329 NUVContext *ctx = s->priv_data;

330 AVIOContext *pb = s->pb;

331 uint8_t hdr[HDRSIZE];

332 nuv_frametype frametype;

333 int size, key, idx;

334 int64_t pos, dts;

335

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

337 return AV_NOPTS_VALUE;

338

339 if (!nuv_resync(s, pos_limit))

340 return AV_NOPTS_VALUE;

341

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

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

344 return AV_NOPTS_VALUE;

345 frametype = hdr[0];

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

347 switch (frametype) {

348 case NUV_SEEKP:

349 break;

350 case NUV_AUDIO:

351 case NUV_VIDEO:

352 if (frametype == NUV_VIDEO) {

353 idx = ctx->v_id;

354 key = hdr[2] == 0;

355 } else {

356 idx = ctx->a_id;

357 key = 1;

358 }

359 if (stream_index == idx) {

360

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

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

363

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

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

366 key ? AVINDEX_KEYFRAME : 0);

367

368 *ppos = pos;

369 return dts;

370 }

371 default:

372 avio_skip(pb, size);

373 break;

374 }

375 }

376 return AV_NOPTS_VALUE;

377 }

378

379

380 AVInputFormat ff_nuv_demuxer = {

381 .name = "nuv",

382 .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo"),

383 .priv_data_size = sizeof(NUVContext),

384 .read_probe = nuv_probe,

385 .read_header = nuv_header,

386 .read_packet = nuv_packet,

387 .read_timestamp = nuv_read_dts,

388 .flags = AVFMT_GENERIC_INDEX,

389 };

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