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/imgutils.h"

24 #include "libavutil/intreadwrite.h"

25 #include "libavutil/intfloat.h"

26 #include "avformat.h"

27 #include "internal.h"

28 #include "riff.h"

30 static const AVCodecTag nuv_audio_tags[] = {

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

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

33 { AV_CODEC_ID_NONE, 0 },

34 };

36 typedef struct NUVContext {

37 int v_id;

38 int a_id;

39 int rtjpg_video;

40 } NUVContext;

42 typedef enum {

43 NUV_VIDEO = 'V',

44 NUV_EXTRADATA = 'D',

45 NUV_AUDIO = 'A',

46 NUV_SEEKP = 'R',

47 NUV_MYTHEXT = 'X'

48 } nuv_frametype;

50 static int nuv_probe(AVProbeData *p)

51 {

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

53 return AVPROBE_SCORE_MAX;

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

55 return AVPROBE_SCORE_MAX;

56 return 0;

57 }

59 /// little macro to sanitize packet size

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

62 /**

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

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

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

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

67 * @return 0 or AVERROR code

68 */

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

70 AVStream *ast, int myth)

71 {

72 nuv_frametype frametype;

74 if (!vst && !myth)

75 return 1; // no codec data needed

76 while (!avio_feof(pb)) {

77 int size, subtype;

79 frametype = avio_r8(pb);

80 switch (frametype) {

81 case NUV_EXTRADATA:

82 subtype = avio_r8(pb);

83 avio_skip(pb, 6);

84 size = PKTSIZE(avio_rl32(pb));

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

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

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

88 vst->codec->extradata_size = 0;

89 }

90 if (ff_get_extradata(vst->codec, pb, size) < 0)

91 return AVERROR(ENOMEM);

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 ret = av_image_check_size(width, height, 0, ctx);

190 if (ret < 0)

191 return ret;

192

193 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

194 vst->codec->codec_id = AV_CODEC_ID_NUV;

195 vst->codec->width = width;

196 vst->codec->height = height;

197 vst->codec->bits_per_coded_sample = 10;

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

199 10000);

200 #if FF_API_R_FRAME_RATE

201 vst->r_frame_rate =

202 #endif

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

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

205 } else

206 ctx->v_id = -1;

207

208 if (a_packs) {

209 ast = avformat_new_stream(s, NULL);

210 if (!ast)

211 return AVERROR(ENOMEM);

212 ctx->a_id = ast->index;

213

214 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

215 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

216 ast->codec->channels = 2;

217 ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;

218 ast->codec->sample_rate = 44100;

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

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

221 ast->codec->bits_per_coded_sample = 16;

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

223 } else

224 ctx->a_id = -1;

225

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

227 return ret;

228

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

230

231 return 0;

232 }

233

234 #define HDRSIZE 12

235

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

237 {

238 NUVContext *ctx = s->priv_data;

239 AVIOContext *pb = s->pb;

240 uint8_t hdr[HDRSIZE];

241 nuv_frametype frametype;

242 int ret, size;

243

244 while (!avio_feof(pb)) {

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

246 uint64_t pos = avio_tell(pb);

247

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

249 if (ret < HDRSIZE)

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

251

252 frametype = hdr[0];

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

254

255 switch (frametype) {

256 case NUV_EXTRADATA:

257 if (!ctx->rtjpg_video) {

258 avio_skip(pb, size);

259 break;

260 }

261 case NUV_VIDEO:

262 if (ctx->v_id < 0) {

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

264 avio_skip(pb, size);

265 break;

266 }

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

268 if (ret < 0)

269 return ret;

270

271 pkt->pos = pos;

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

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

274 pkt->stream_index = ctx->v_id;

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

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

277 if (ret < 0) {

278 av_free_packet(pkt);

279 return ret;

280 }

281 if (ret < size)

282 av_shrink_packet(pkt, copyhdrsize + ret);

283 return 0;

284 case NUV_AUDIO:

285 if (ctx->a_id < 0) {

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

287 avio_skip(pb, size);

288 break;

289 }

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

291 pkt->flags |= AV_PKT_FLAG_KEY;

292 pkt->pos = pos;

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

294 pkt->stream_index = ctx->a_id;

295 if (ret < 0)

296 return ret;

297 return 0;

298 case NUV_SEEKP:

299 // contains no data, size value is invalid

300 break;

301 default:

302 avio_skip(pb, size);

303 break;

304 }

305 }

306

307 return AVERROR(EIO);

308 }

309

310 /**

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

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

313 */

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

315 AVIOContext *pb = s->pb;

316 uint32_t tag = 0;

317 while(!avio_feof(pb) && avio_tell(pb) < pos_limit) {

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

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

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

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

322 return 1;

323 }

324 return 0;

325 }

326

327 /**

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

329 * \return timestamp if successful and AV_NOPTS_VALUE if failure

330 */

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

332 int64_t *ppos, int64_t pos_limit)

333 {

334 NUVContext *ctx = s->priv_data;

335 AVIOContext *pb = s->pb;

336 uint8_t hdr[HDRSIZE];

337 nuv_frametype frametype;

338 int size, key, idx;

339 int64_t pos, dts;

340

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

342 return AV_NOPTS_VALUE;

343

344 if (!nuv_resync(s, pos_limit))

345 return AV_NOPTS_VALUE;

346

347 while (!avio_feof(pb) && avio_tell(pb) < pos_limit) {

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

349 return AV_NOPTS_VALUE;

350 frametype = hdr[0];

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

352 switch (frametype) {

353 case NUV_SEEKP:

354 break;

355 case NUV_AUDIO:

356 case NUV_VIDEO:

357 if (frametype == NUV_VIDEO) {

358 idx = ctx->v_id;

359 key = hdr[2] == 0;

360 } else {

361 idx = ctx->a_id;

362 key = 1;

363 }

364 if (stream_index == idx) {

365

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

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

368

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

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

371 key ? AVINDEX_KEYFRAME : 0);

372

373 *ppos = pos;

374 return dts;

375 }

376 default:

377 avio_skip(pb, size);

378 break;

379 }

380 }

381 return AV_NOPTS_VALUE;

382 }

383

384

385 AVInputFormat ff_nuv_demuxer = {

386 .name = "nuv",

387 .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo"),

388 .priv_data_size = sizeof(NUVContext),

389 .read_probe = nuv_probe,

390 .read_header = nuv_header,

391 .read_packet = nuv_packet,

392 .read_timestamp = nuv_read_dts,

393 .flags = AVFMT_GENERIC_INDEX,

394 };

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