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 Libav.
15  *
16  * Libav 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  * Libav 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 Libav; 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/dvdata.h"
36 #include "dv.h"
37 #include "libavutil/fifo.h"
38 #include "libavutil/mathematics.h"
39 
40 struct DVMuxContext {
41  const DVprofile* sys; /* current DV profile, e.g.: 525/60, 625/50 */
42  int n_ast; /* number of stereo audio streams (up to 2) */
43  AVStream *ast[2]; /* stereo audio streams */
44  AVFifoBuffer *audio_data[2]; /* FIFO for storing excessive amounts of PCM */
45  int frames; /* current frame number */
46  int64_t start_time; /* recording start time */
47  int has_audio; /* frame under contruction has audio */
48  int has_video; /* frame under contruction has video */
49  uint8_t frame_buf[DV_MAX_FRAME_SIZE]; /* frame under contruction */
50 };
51 
52 static const int dv_aaux_packs_dist[12][9] = {
53  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
54  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
55  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
56  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
57  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
58  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
59  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
60  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
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 };
66 
67 static int dv_audio_frame_size(const DVprofile* sys, int frame)
68 {
69  return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
70  sizeof(sys->audio_samples_dist[0]))];
71 }
72 
73 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
74 {
75  struct tm tc;
76  time_t ct;
77  int ltc_frame;
78  va_list ap;
79 
80  buf[0] = (uint8_t)pack_id;
81  switch (pack_id) {
82  case dv_timecode:
83  ct = (time_t)av_rescale_rnd(c->frames, c->sys->time_base.num,
85  brktimegm(ct, &tc);
86  /*
87  * LTC drop-frame frame counter drops two frames (0 and 1) every
88  * minute, unless it is exactly divisible by 10
89  */
90  ltc_frame = (c->frames + 2 * ct / 60 - 2 * ct / 600) % c->sys->ltc_divisor;
91  buf[1] = (0 << 7) | /* color frame: 0 - unsync; 1 - sync mode */
92  (1 << 6) | /* drop frame timecode: 0 - nondrop; 1 - drop */
93  ((ltc_frame / 10) << 4) | /* tens of frames */
94  (ltc_frame % 10); /* units of frames */
95  buf[2] = (1 << 7) | /* biphase mark polarity correction: 0 - even; 1 - odd */
96  ((tc.tm_sec / 10) << 4) | /* tens of seconds */
97  (tc.tm_sec % 10); /* units of seconds */
98  buf[3] = (1 << 7) | /* binary group flag BGF0 */
99  ((tc.tm_min / 10) << 4) | /* tens of minutes */
100  (tc.tm_min % 10); /* units of minutes */
101  buf[4] = (1 << 7) | /* binary group flag BGF2 */
102  (1 << 6) | /* binary group flag BGF1 */
103  ((tc.tm_hour / 10) << 4) | /* tens of hours */
104  (tc.tm_hour % 10); /* units of hours */
105  break;
106  case dv_audio_source: /* AAUX source pack */
107  va_start(ap, buf);
108  buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
109  (1 << 6) | /* reserved -- always 1 */
110  (dv_audio_frame_size(c->sys, c->frames) -
111  c->sys->audio_min_samples[0]);
112  /* # of samples */
113  buf[2] = (0 << 7) | /* multi-stereo */
114  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
115  (0 << 4) | /* pair bit: 0 -- one pair of channels */
116  !!va_arg(ap, int); /* audio mode */
117  buf[3] = (1 << 7) | /* res */
118  (1 << 6) | /* multi-language flag */
119  (c->sys->dsf << 5) | /* system: 60fields/50fields */
120  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
121  buf[4] = (1 << 7) | /* emphasis: 1 -- off */
122  (0 << 6) | /* emphasis time constant: 0 -- reserved */
123  (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
124  0; /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
125  va_end(ap);
126  break;
127  case dv_audio_control:
128  buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
129  (1 << 4) | /* input source: 1 -- digital input */
130  (3 << 2) | /* compression: 3 -- no information */
131  0; /* misc. info/SMPTE emphasis off */
132  buf[2] = (1 << 7) | /* recording start point: 1 -- no */
133  (1 << 6) | /* recording end point: 1 -- no */
134  (1 << 3) | /* recording mode: 1 -- original */
135  7;
136  buf[3] = (1 << 7) | /* direction: 1 -- forward */
137  (c->sys->pix_fmt == PIX_FMT_YUV420P ? 0x20 : /* speed */
138  c->sys->ltc_divisor * 4);
139  buf[4] = (1 << 7) | /* reserved -- always 1 */
140  0x7f; /* genre category */
141  break;
142  case dv_audio_recdate:
143  case dv_video_recdate: /* VAUX recording date */
144  ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
146  brktimegm(ct, &tc);
147  buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
148  /* 0xff is very likely to be "unknown" */
149  buf[2] = (3 << 6) | /* reserved -- always 1 */
150  ((tc.tm_mday / 10) << 4) | /* Tens of day */
151  (tc.tm_mday % 10); /* Units of day */
152  buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
153  ((tc.tm_mon / 10) << 4) | /* Tens of month */
154  (tc.tm_mon % 10); /* Units of month */
155  buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
156  (tc.tm_year % 10); /* Units of year */
157  break;
158  case dv_audio_rectime: /* AAUX recording time */
159  case dv_video_rectime: /* VAUX recording time */
160  ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
162  brktimegm(ct, &tc);
163  buf[1] = (3 << 6) | /* reserved -- always 1 */
164  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
165  buf[2] = (1 << 7) | /* reserved -- always 1 */
166  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
167  (tc.tm_sec % 10); /* Units of seconds */
168  buf[3] = (1 << 7) | /* reserved -- always 1 */
169  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
170  (tc.tm_min % 10); /* Units of minutes */
171  buf[4] = (3 << 6) | /* reserved -- always 1 */
172  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
173  (tc.tm_hour % 10); /* Units of hours */
174  break;
175  default:
176  buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
177  }
178  return 5;
179 }
180 
181 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
182 {
183  int i, j, d, of, size;
184  size = 4 * dv_audio_frame_size(c->sys, c->frames);
185  frame_ptr += channel * c->sys->difseg_size * 150 * 80;
186  for (i = 0; i < c->sys->difseg_size; i++) {
187  frame_ptr += 6 * 80; /* skip DIF segment header */
188  for (j = 0; j < 9; j++) {
189  dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
190  for (d = 8; d < 80; d+=2) {
191  of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
192  if (of*2 >= size)
193  continue;
194 
195  frame_ptr[d] = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
196  frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2); // that DV is a big-endian PCM
197  }
198  frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
199  }
200  }
201 }
202 
203 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
204 {
205  int j, k;
206  uint8_t* buf;
207 
208  for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
209  /* DV subcode: 2nd and 3d DIFs */
210  for (j = 80; j < 80 * 3; j += 80) {
211  for (k = 6; k < 6 * 8; k += 8)
212  dv_write_pack(dv_timecode, c, &buf[j+k]);
213 
214  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 ? */
215  dv_write_pack(dv_video_recdate, c, &buf[j+14]);
216  dv_write_pack(dv_video_rectime, c, &buf[j+22]);
217  dv_write_pack(dv_video_recdate, c, &buf[j+38]);
218  dv_write_pack(dv_video_rectime, c, &buf[j+46]);
219  }
220  }
221 
222  /* DV VAUX: 4th, 5th and 6th 3DIFs */
223  for (j = 80*3 + 3; j < 80*6; j += 80) {
224  dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
225  dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
226  dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
227  dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
228  }
229  }
230 }
231 
232 /*
233  * The following 3 functions constitute our interface to the world
234  */
235 
237  uint8_t* data, int data_size, uint8_t** frame)
238 {
239  int i, reqasize;
240 
241  *frame = &c->frame_buf[0];
242  reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
243 
244  switch (st->codec->codec_type) {
245  case AVMEDIA_TYPE_VIDEO:
246  /* FIXME: we have to have more sensible approach than this one */
247  if (c->has_video)
248  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
249 
250  memcpy(*frame, data, c->sys->frame_size);
251  c->has_video = 1;
252  break;
253  case AVMEDIA_TYPE_AUDIO:
254  for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
255 
256  /* FIXME: we have to have more sensible approach than this one */
257  if (av_fifo_size(c->audio_data[i]) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)
258  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
259  av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);
260 
261  /* Let us see if we've got enough audio for one DV frame. */
262  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
263 
264  break;
265  default:
266  break;
267  }
268 
269  /* Let us see if we have enough data to construct one DV frame. */
270  if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
271  dv_inject_metadata(c, *frame);
272  c->has_audio = 0;
273  for (i=0; i < c->n_ast; i++) {
274  dv_inject_audio(c, i, *frame);
275  av_fifo_drain(c->audio_data[i], reqasize);
276  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
277  }
278 
279  c->has_video = 0;
280 
281  c->frames++;
282 
283  return c->sys->frame_size;
284  }
285 
286  return 0;
287 }
288 
290 {
291  DVMuxContext *c = s->priv_data;
292  AVStream *vst = NULL;
294  int i;
295 
296  /* we support at most 1 video and 2 audio streams */
297  if (s->nb_streams > 3)
298  return NULL;
299 
300  c->n_ast = 0;
301  c->ast[0] = c->ast[1] = NULL;
302 
303  /* We have to sort out where audio and where video stream is */
304  for (i=0; i<s->nb_streams; i++) {
305  switch (s->streams[i]->codec->codec_type) {
306  case AVMEDIA_TYPE_VIDEO:
307  if (vst) return NULL;
308  vst = s->streams[i];
309  break;
310  case AVMEDIA_TYPE_AUDIO:
311  if (c->n_ast > 1) return NULL;
312  c->ast[c->n_ast++] = s->streams[i];
313  break;
314  default:
315  goto bail_out;
316  }
317  }
318 
319  /* Some checks -- DV format is very picky about its incoming streams */
320  if (!vst || vst->codec->codec_id != CODEC_ID_DVVIDEO)
321  goto bail_out;
322  for (i=0; i<c->n_ast; i++) {
323  if (c->ast[i] && (c->ast[i]->codec->codec_id != CODEC_ID_PCM_S16LE ||
324  c->ast[i]->codec->sample_rate != 48000 ||
325  c->ast[i]->codec->channels != 2))
326  goto bail_out;
327  }
328  c->sys = avpriv_dv_codec_profile(vst->codec);
329  if (!c->sys)
330  goto bail_out;
331 
332  if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
333  /* only 1 stereo pair is allowed in 25Mbps mode */
334  goto bail_out;
335  }
336 
337  /* Ok, everything seems to be in working order */
338  c->frames = 0;
339  c->has_audio = 0;
340  c->has_video = 0;
341 #if FF_API_TIMESTAMP
342  if (s->timestamp)
343  c->start_time = s->timestamp;
344  else
345 #endif
346  if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
348 
349  for (i=0; i < c->n_ast; i++) {
350  if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc(100*AVCODEC_MAX_AUDIO_FRAME_SIZE))) {
351  while (i > 0) {
352  i--;
353  av_fifo_free(c->audio_data[i]);
354  }
355  goto bail_out;
356  }
357  }
358 
359  return c;
360 
361 bail_out:
362  return NULL;
363 }
364 
366 {
367  int i;
368  for (i=0; i < c->n_ast; i++)
369  av_fifo_free(c->audio_data[i]);
370 }
371 
373 {
374  if (!dv_init_mux(s)) {
375  av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
376  "Make sure that you supply exactly two streams:\n"
377  " video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
378  " (50Mbps allows an optional second audio stream)\n");
379  return -1;
380  }
381  return 0;
382 }
383 
384 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
385 {
386  uint8_t* frame;
387  int fsize;
388 
389  fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],
390  pkt->data, pkt->size, &frame);
391  if (fsize > 0) {
392  avio_write(s->pb, frame, fsize);
393  avio_flush(s->pb);
394  }
395  return 0;
396 }
397 
398 /*
399  * We might end up with some extra A/V data without matching counterpart.
400  * E.g. video data without enough audio to write the complete frame.
401  * Currently we simply drop the last frame. I don't know whether this
402  * is the best strategy of all
403  */
404 static int dv_write_trailer(struct AVFormatContext *s)
405 {
407  return 0;
408 }
409 
411  .name = "dv",
412  .long_name = NULL_IF_CONFIG_SMALL("DV video format"),
413  .extensions = "dv",
414  .priv_data_size = sizeof(DVMuxContext),
415  .audio_codec = CODEC_ID_PCM_S16LE,
416  .video_codec = CODEC_ID_DVVIDEO,
420 };