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dvenc.c
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1 /*
2  * General DV muxer/demuxer
3  * Copyright (c) 2003 Roman Shaposhnik
4  *
5  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
6  * of DV technical info.
7  *
8  * Raw DV format
9  * Copyright (c) 2002 Fabrice Bellard
10  *
11  * 50 Mbps (DVCPRO50) support
12  * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
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>
32 
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"
43 
44 #define MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audio
45 
46 struct DVMuxContext {
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 };
59 
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 };
74 
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  }
82 
83  av_assert0(sample_rate == 48000);
84 
85  return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
86  sizeof(sys->audio_samples_dist[0]))];
87 }
88 
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;
97 
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,
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,
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 
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 
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 
297 {
298  DVMuxContext *c = s->priv_data;
299  AVStream *vst = NULL;
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))
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 
381 {
382  int i;
383  for (i=0; i < c->n_ast; i++)
384  av_fifo_freep(&c->audio_data[i]);
385 }
386 
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 
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 {
437  return 0;
438 }
439 
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,
450 };