FFmpeg: libavformat/dvenc.c Source File

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libavformat

dvenc.c

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1 /*

2 * General DV muxer/demuxer

4 *

5 * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth

6 * of DV technical info.

7 *

8 * Raw DV format

10 *

11 * 50 Mbps (DVCPRO50) support

13 *

14 * This file is part of FFmpeg.

15 *

16 * FFmpeg is free software; you can redistribute it and/or

17 * modify it under the terms of the GNU Lesser General Public

18 * License as published by the Free Software Foundation; either

19 * version 2.1 of the License, or (at your option) any later version.

20 *

21 * FFmpeg is distributed in the hope that it will be useful,

22 * but WITHOUT ANY WARRANTY; without even the implied warranty of

23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

24 * Lesser General Public License for more details.

25 *

26 * You should have received a copy of the GNU Lesser General Public

27 * License along with FFmpeg; if not, write to the Free Software

28 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

29 */

30 #include <time.h>

31 #include <stdarg.h>

33 #include "avformat.h"

34 #include "internal.h"

35 #include "libavcodec/dv_profile.h"

36 #include "libavcodec/dv.h"

37 #include "dv.h"

38 #include "libavutil/fifo.h"

39 #include "libavutil/mathematics.h"

40 #include "libavutil/intreadwrite.h"

41 #include "libavutil/opt.h"

42 #include "libavutil/timecode.h"

44 #define MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audio

46 struct DVMuxContext {

47 AVClass *av_class;

48 const AVDVProfile* sys; /* current DV profile, e.g.: 525/60, 625/50 */

49 int n_ast; /* number of stereo audio streams (up to 2) */

50 AVStream *ast[2]; /* stereo audio streams */

51 AVFifoBuffer *audio_data[2]; /* FIFO for storing excessive amounts of PCM */

52 int frames; /* current frame number */

53 int64_t start_time; /* recording start time */

54 int has_audio; /* frame under construction has audio */

55 int has_video; /* frame under construction has video */

56 uint8_t frame_buf[DV_MAX_FRAME_SIZE]; /* frame under construction */

57 AVTimecode tc; /* timecode context */

58 };

60 static const int dv_aaux_packs_dist[12][9] = {

61 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

62 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

63 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

64 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

65 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

66 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

67 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

68 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

69 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

70 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

71 { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

72 { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

73 };

75 static int dv_audio_frame_size(const AVDVProfile* sys, int frame, int sample_rate)

76 {

77 if ((sys->time_base.den == 25 || sys->time_base.den == 50) && sys->time_base.num == 1) {

78 if (sample_rate == 32000) return 1280;

79 else if (sample_rate == 44100) return 1764;

80 else return 1920;

81 }

83 av_assert0(sample_rate == 48000);

85 return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /

86 sizeof(sys->audio_samples_dist[0]))];

87 }

89 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)

90 {

91 struct tm tc;

92 time_t ct;

93 uint32_t timecode;

94 va_list ap;

95 int audio_type = 0;

96 int channel;

98 buf[0] = (uint8_t)pack_id;

99 switch (pack_id) {

100 case dv_timecode:

101 timecode = av_timecode_get_smpte_from_framenum(&c->tc, c->frames);

102 timecode |= 1<<23 | 1<<15 | 1<<7 | 1<<6; // biphase and binary group flags

103 AV_WB32(buf + 1, timecode);

104 break;

105 case dv_audio_source: /* AAUX source pack */

106 va_start(ap, buf);

107 channel = va_arg(ap, int);

108 if (c->ast[channel]->codec->sample_rate == 44100) {

109 audio_type = 1;

110 } else if (c->ast[channel]->codec->sample_rate == 32000)

111 audio_type = 2;

112 buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */

113 (1 << 6) | /* reserved -- always 1 */

114 (dv_audio_frame_size(c->sys, c->frames, c->ast[channel]->codec->sample_rate) -

115 c->sys->audio_min_samples[audio_type]);

116 /* # of samples */

117 buf[2] = (0 << 7) | /* multi-stereo */

118 (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */

119 (0 << 4) | /* pair bit: 0 -- one pair of channels */

120 !!va_arg(ap, int); /* audio mode */

121 buf[3] = (1 << 7) | /* res */

122 (1 << 6) | /* multi-language flag */

123 (c->sys->dsf << 5) | /* system: 60fields/50fields */

124 (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */

125 buf[4] = (1 << 7) | /* emphasis: 1 -- off */

126 (0 << 6) | /* emphasis time constant: 0 -- reserved */

127 (audio_type << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */

128 0; /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */

129

130 va_end(ap);

131 break;

132 case dv_audio_control:

133 buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */

134 (1 << 4) | /* input source: 1 -- digital input */

135 (3 << 2) | /* compression: 3 -- no information */

136 0; /* misc. info/SMPTE emphasis off */

137 buf[2] = (1 << 7) | /* recording start point: 1 -- no */

138 (1 << 6) | /* recording end point: 1 -- no */

139 (1 << 3) | /* recording mode: 1 -- original */

140 7;

141 buf[3] = (1 << 7) | /* direction: 1 -- forward */

142 (c->sys->pix_fmt == AV_PIX_FMT_YUV420P ? 0x20 : /* speed */

143 c->sys->ltc_divisor * 4);

144 buf[4] = (1 << 7) | /* reserved -- always 1 */

145 0x7f; /* genre category */

146 break;

147 case dv_audio_recdate:

148 case dv_video_recdate: /* VAUX recording date */

149 ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,

150 c->sys->time_base.den, AV_ROUND_DOWN);

151 ff_brktimegm(ct, &tc);

152 buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */

153 /* 0xff is very likely to be "unknown" */

154 buf[2] = (3 << 6) | /* reserved -- always 1 */

155 ((tc.tm_mday / 10) << 4) | /* Tens of day */

156 (tc.tm_mday % 10); /* Units of day */

157 buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */

158 ((tc.tm_mon / 10) << 4) | /* Tens of month */

159 (tc.tm_mon % 10); /* Units of month */

160 buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */

161 (tc.tm_year % 10); /* Units of year */

162 break;

163 case dv_audio_rectime: /* AAUX recording time */

164 case dv_video_rectime: /* VAUX recording time */

165 ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,

166 c->sys->time_base.den, AV_ROUND_DOWN);

167 ff_brktimegm(ct, &tc);

168 buf[1] = (3 << 6) | /* reserved -- always 1 */

169 0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */

170 buf[2] = (1 << 7) | /* reserved -- always 1 */

171 ((tc.tm_sec / 10) << 4) | /* Tens of seconds */

172 (tc.tm_sec % 10); /* Units of seconds */

173 buf[3] = (1 << 7) | /* reserved -- always 1 */

174 ((tc.tm_min / 10) << 4) | /* Tens of minutes */

175 (tc.tm_min % 10); /* Units of minutes */

176 buf[4] = (3 << 6) | /* reserved -- always 1 */

177 ((tc.tm_hour / 10) << 4) | /* Tens of hours */

178 (tc.tm_hour % 10); /* Units of hours */

179 break;

180 default:

181 buf[1] = buf[2] = buf[3] = buf[4] = 0xff;

182 }

183 return 5;

184 }

185

186 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)

187 {

188 int i, j, d, of, size;

189 size = 4 * dv_audio_frame_size(c->sys, c->frames, c->ast[channel]->codec->sample_rate);

190 frame_ptr += channel * c->sys->difseg_size * 150 * 80;

191 for (i = 0; i < c->sys->difseg_size; i++) {

192 frame_ptr += 6 * 80; /* skip DIF segment header */

193 for (j = 0; j < 9; j++) {

194 dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], channel, i >= c->sys->difseg_size/2);

195 for (d = 8; d < 80; d+=2) {

196 of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;

197 if (of*2 >= size)

198 continue;

199

200 frame_ptr[d] = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit

201 frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2); // that DV is a big-endian PCM

202 }

203 frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */

204 }

205 }

206 }

207

208 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)

209 {

210 int j, k;

211 uint8_t* buf;

212

213 for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {

214 /* DV subcode: 2nd and 3d DIFs */

215 for (j = 80; j < 80 * 3; j += 80) {

216 for (k = 6; k < 6 * 8; k += 8)

217 dv_write_pack(dv_timecode, c, &buf[j+k]);

218

219 if (((long)(buf-frame)/(c->sys->frame_size/(c->sys->difseg_size*c->sys->n_difchan))%c->sys->difseg_size) > 5) { /* FIXME: is this really needed ? */

220 dv_write_pack(dv_video_recdate, c, &buf[j+14]);

221 dv_write_pack(dv_video_rectime, c, &buf[j+22]);

222 dv_write_pack(dv_video_recdate, c, &buf[j+38]);

223 dv_write_pack(dv_video_rectime, c, &buf[j+46]);

224 }

225 }

226

227 /* DV VAUX: 4th, 5th and 6th 3DIFs */

228 for (j = 80*3 + 3; j < 80*6; j += 80) {

229 dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);

230 dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);

231 dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);

232 dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);

233 }

234 }

235 }

236

237 /*

238 * The following 3 functions constitute our interface to the world

239 */

240

241 static int dv_assemble_frame(DVMuxContext *c, AVStream* st,

242 uint8_t* data, int data_size, uint8_t** frame)

243 {

244 int i, reqasize;

245

246 *frame = &c->frame_buf[0];

247

248 switch (st->codec->codec_type) {

249 case AVMEDIA_TYPE_VIDEO:

250 /* FIXME: we have to have more sensible approach than this one */

251 if (c->has_video)

252 av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);

253

254 memcpy(*frame, data, c->sys->frame_size);

255 c->has_video = 1;

256 break;

257 case AVMEDIA_TYPE_AUDIO:

258 for (i = 0; i < c->n_ast && st != c->ast[i]; i++);

259

260 /* FIXME: we have to have more sensible approach than this one */

261 if (av_fifo_size(c->audio_data[i]) + data_size >= 100*MAX_AUDIO_FRAME_SIZE)

262 av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);

263 av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);

264

265 reqasize = 4 * dv_audio_frame_size(c->sys, c->frames, st->codec->sample_rate);

266

267 /* Let us see if we've got enough audio for one DV frame. */

268 c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);

269

270 break;

271 default:

272 break;

273 }

274

275 /* Let us see if we have enough data to construct one DV frame. */

276 if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {

277 dv_inject_metadata(c, *frame);

278 c->has_audio = 0;

279 for (i=0; i < c->n_ast; i++) {

280 dv_inject_audio(c, i, *frame);

281 reqasize = 4 * dv_audio_frame_size(c->sys, c->frames, c->ast[i]->codec->sample_rate);

282 av_fifo_drain(c->audio_data[i], reqasize);

283 c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);

284 }

285

286 c->has_video = 0;

287

288 c->frames++;

289

290 return c->sys->frame_size;

291 }

292

293 return 0;

294 }

295

296 static DVMuxContext* dv_init_mux(AVFormatContext* s)

297 {

298 DVMuxContext *c = s->priv_data;

299 AVStream *vst = NULL;

300 AVDictionaryEntry *t;

301 int i;

302

303 /* we support at most 1 video and 2 audio streams */

304 if (s->nb_streams > 3)

305 return NULL;

306

307 c->n_ast = 0;

308 c->ast[0] = c->ast[1] = NULL;

309

310 /* We have to sort out where audio and where video stream is */

311 for (i=0; i<s->nb_streams; i++) {

312 switch (s->streams[i]->codec->codec_type) {

313 case AVMEDIA_TYPE_VIDEO:

314 if (vst) return NULL;

315 vst = s->streams[i];

316 break;

317 case AVMEDIA_TYPE_AUDIO:

318 if (c->n_ast > 1) return NULL;

319 c->ast[c->n_ast++] = s->streams[i];

320 break;

321 default:

322 goto bail_out;

323 }

324 }

325

326 /* Some checks -- DV format is very picky about its incoming streams */

327 if (!vst || vst->codec->codec_id != AV_CODEC_ID_DVVIDEO)

328 goto bail_out;

329 for (i=0; i<c->n_ast; i++) {

330 if (c->ast[i]) {

331 if(c->ast[i]->codec->codec_id != AV_CODEC_ID_PCM_S16LE ||

332 c->ast[i]->codec->channels != 2)

333 goto bail_out;

334 if (c->ast[i]->codec->sample_rate != 48000 &&

335 c->ast[i]->codec->sample_rate != 44100 &&

336 c->ast[i]->codec->sample_rate != 32000 )

337 goto bail_out;

338 }

339 }

340 c->sys = av_dv_codec_profile2(vst->codec->width, vst->codec->height,

341 vst->codec->pix_fmt, vst->codec->time_base);

342 if (!c->sys)

343 goto bail_out;

344

345 if ((c->sys->time_base.den != 25 && c->sys->time_base.den != 50) || c->sys->time_base.num != 1) {

346 if (c->ast[0] && c->ast[0]->codec->sample_rate != 48000)

347 goto bail_out;

348 if (c->ast[1] && c->ast[1]->codec->sample_rate != 48000)

349 goto bail_out;

350 }

351

352 if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {

353 /* only 1 stereo pair is allowed in 25Mbps mode */

354 goto bail_out;

355 }

356

357 /* Ok, everything seems to be in working order */

358 c->frames = 0;

359 c->has_audio = 0;

360 c->has_video = 0;

361 if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))

362 c->start_time = ff_iso8601_to_unix_time(t->value);

363

364 for (i=0; i < c->n_ast; i++) {

365 if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc_array(100, MAX_AUDIO_FRAME_SIZE))) {

366 while (i > 0) {

367 i--;

368 av_fifo_freep(&c->audio_data[i]);

369 }

370 goto bail_out;

371 }

372 }

373

374 return c;

375

376 bail_out:

377 return NULL;

378 }

379

380 static void dv_delete_mux(DVMuxContext *c)

381 {

382 int i;

383 for (i=0; i < c->n_ast; i++)

384 av_fifo_freep(&c->audio_data[i]);

385 }

386

387 static int dv_write_header(AVFormatContext *s)

388 {

389 AVRational rate;

390 DVMuxContext *dvc = s->priv_data;

391 AVDictionaryEntry *tcr = av_dict_get(s->metadata, "timecode", NULL, 0);

392

393 if (!dv_init_mux(s)) {

394 av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"

395 "Make sure that you supply exactly two streams:\n"

396 " video: 25fps or 29.97fps, audio: 2ch/48|44|32kHz/PCM\n"

397 " (50Mbps allows an optional second audio stream)\n");

398 return -1;

399 }

400 rate.num = dvc->sys->ltc_divisor;

401 rate.den = 1;

402 if (!tcr) { // no global timecode, look into the streams

403 int i;

404 for (i = 0; i < s->nb_streams; i++) {

405 tcr = av_dict_get(s->streams[i]->metadata, "timecode", NULL, 0);

406 if (tcr)

407 break;

408 }

409 }

410 if (tcr && av_timecode_init_from_string(&dvc->tc, rate, tcr->value, s) >= 0)

411 return 0;

412 return av_timecode_init(&dvc->tc, rate, 0, 0, s);

413 }

414

415 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)

416 {

417 uint8_t* frame;

418 int fsize;

419

420 fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],

421 pkt->data, pkt->size, &frame);

422 if (fsize > 0) {

423 avio_write(s->pb, frame, fsize);

424 }

425 return 0;

426 }

427

428 /*

429 * We might end up with some extra A/V data without matching counterpart.

430 * E.g. video data without enough audio to write the complete frame.

431 * Currently we simply drop the last frame. I don't know whether this

432 * is the best strategy of all

433 */

434 static int dv_write_trailer(struct AVFormatContext *s)

435 {

436 dv_delete_mux(s->priv_data);

437 return 0;

438 }

439

440 AVOutputFormat ff_dv_muxer = {

441 .name = "dv",

442 .long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),

443 .extensions = "dv",

444 .priv_data_size = sizeof(DVMuxContext),

445 .audio_codec = AV_CODEC_ID_PCM_S16LE,

446 .video_codec = AV_CODEC_ID_DVVIDEO,

447 .write_header = dv_write_header,

448 .write_packet = dv_write_packet,

449 .write_trailer = dv_write_trailer,

450 };

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