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/dv_profile.h"
36 #include "libavcodec/dvdata.h"
37 #include "dv.h"
38 #include "libavutil/fifo.h"
39 #include "libavutil/mathematics.h"
40 
41 #define MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audio
42 
43 struct DVMuxContext {
44  const DVprofile* sys; /* current DV profile, e.g.: 525/60, 625/50 */
45  int n_ast; /* number of stereo audio streams (up to 2) */
46  AVStream *ast[2]; /* stereo audio streams */
47  AVFifoBuffer *audio_data[2]; /* FIFO for storing excessive amounts of PCM */
48  int frames; /* current frame number */
49  int64_t start_time; /* recording start time */
50  int has_audio; /* frame under construction has audio */
51  int has_video; /* frame under construction has video */
52  uint8_t frame_buf[DV_MAX_FRAME_SIZE]; /* frame under construction */
53 };
54 
55 static const int dv_aaux_packs_dist[12][9] = {
56  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
57  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
58  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
59  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
60  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
61  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
62  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
63  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
64  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
65  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
66  { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
67  { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
68 };
69 
70 static int dv_audio_frame_size(const DVprofile* sys, int frame)
71 {
72  return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
73  sizeof(sys->audio_samples_dist[0]))];
74 }
75 
76 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
77 {
78  struct tm tc;
79  time_t ct;
80  int ltc_frame;
81  va_list ap;
82 
83  buf[0] = (uint8_t)pack_id;
84  switch (pack_id) {
85  case dv_timecode:
86  ct = (time_t)av_rescale_rnd(c->frames, c->sys->time_base.num,
88  ff_brktimegm(ct, &tc);
89  /*
90  * LTC drop-frame frame counter drops two frames (0 and 1) every
91  * minute, unless it is exactly divisible by 10
92  */
93  ltc_frame = (c->frames + 2 * ct / 60 - 2 * ct / 600) % c->sys->ltc_divisor;
94  buf[1] = (0 << 7) | /* color frame: 0 - unsync; 1 - sync mode */
95  (1 << 6) | /* drop frame timecode: 0 - nondrop; 1 - drop */
96  ((ltc_frame / 10) << 4) | /* tens of frames */
97  (ltc_frame % 10); /* units of frames */
98  buf[2] = (1 << 7) | /* biphase mark polarity correction: 0 - even; 1 - odd */
99  ((tc.tm_sec / 10) << 4) | /* tens of seconds */
100  (tc.tm_sec % 10); /* units of seconds */
101  buf[3] = (1 << 7) | /* binary group flag BGF0 */
102  ((tc.tm_min / 10) << 4) | /* tens of minutes */
103  (tc.tm_min % 10); /* units of minutes */
104  buf[4] = (1 << 7) | /* binary group flag BGF2 */
105  (1 << 6) | /* binary group flag BGF1 */
106  ((tc.tm_hour / 10) << 4) | /* tens of hours */
107  (tc.tm_hour % 10); /* units of hours */
108  break;
109  case dv_audio_source: /* AAUX source pack */
110  va_start(ap, buf);
111  buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
112  (1 << 6) | /* reserved -- always 1 */
113  (dv_audio_frame_size(c->sys, c->frames) -
114  c->sys->audio_min_samples[0]);
115  /* # of samples */
116  buf[2] = (0 << 7) | /* multi-stereo */
117  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
118  (0 << 4) | /* pair bit: 0 -- one pair of channels */
119  !!va_arg(ap, int); /* audio mode */
120  buf[3] = (1 << 7) | /* res */
121  (1 << 6) | /* multi-language flag */
122  (c->sys->dsf << 5) | /* system: 60fields/50fields */
123  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
124  buf[4] = (1 << 7) | /* emphasis: 1 -- off */
125  (0 << 6) | /* emphasis time constant: 0 -- reserved */
126  (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
127  0; /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
128  va_end(ap);
129  break;
130  case dv_audio_control:
131  buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
132  (1 << 4) | /* input source: 1 -- digital input */
133  (3 << 2) | /* compression: 3 -- no information */
134  0; /* misc. info/SMPTE emphasis off */
135  buf[2] = (1 << 7) | /* recording start point: 1 -- no */
136  (1 << 6) | /* recording end point: 1 -- no */
137  (1 << 3) | /* recording mode: 1 -- original */
138  7;
139  buf[3] = (1 << 7) | /* direction: 1 -- forward */
140  (c->sys->pix_fmt == AV_PIX_FMT_YUV420P ? 0x20 : /* speed */
141  c->sys->ltc_divisor * 4);
142  buf[4] = (1 << 7) | /* reserved -- always 1 */
143  0x7f; /* genre category */
144  break;
145  case dv_audio_recdate:
146  case dv_video_recdate: /* VAUX recording date */
147  ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
149  ff_brktimegm(ct, &tc);
150  buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
151  /* 0xff is very likely to be "unknown" */
152  buf[2] = (3 << 6) | /* reserved -- always 1 */
153  ((tc.tm_mday / 10) << 4) | /* Tens of day */
154  (tc.tm_mday % 10); /* Units of day */
155  buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
156  ((tc.tm_mon / 10) << 4) | /* Tens of month */
157  (tc.tm_mon % 10); /* Units of month */
158  buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
159  (tc.tm_year % 10); /* Units of year */
160  break;
161  case dv_audio_rectime: /* AAUX recording time */
162  case dv_video_rectime: /* VAUX recording time */
163  ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
165  ff_brktimegm(ct, &tc);
166  buf[1] = (3 << 6) | /* reserved -- always 1 */
167  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
168  buf[2] = (1 << 7) | /* reserved -- always 1 */
169  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
170  (tc.tm_sec % 10); /* Units of seconds */
171  buf[3] = (1 << 7) | /* reserved -- always 1 */
172  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
173  (tc.tm_min % 10); /* Units of minutes */
174  buf[4] = (3 << 6) | /* reserved -- always 1 */
175  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
176  (tc.tm_hour % 10); /* Units of hours */
177  break;
178  default:
179  buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
180  }
181  return 5;
182 }
183 
184 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
185 {
186  int i, j, d, of, size;
187  size = 4 * dv_audio_frame_size(c->sys, c->frames);
188  frame_ptr += channel * c->sys->difseg_size * 150 * 80;
189  for (i = 0; i < c->sys->difseg_size; i++) {
190  frame_ptr += 6 * 80; /* skip DIF segment header */
191  for (j = 0; j < 9; j++) {
192  dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
193  for (d = 8; d < 80; d+=2) {
194  of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
195  if (of*2 >= size)
196  continue;
197 
198  frame_ptr[d] = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
199  frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2); // that DV is a big-endian PCM
200  }
201  frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
202  }
203  }
204 }
205 
206 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
207 {
208  int j, k;
209  uint8_t* buf;
210 
211  for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
212  /* DV subcode: 2nd and 3d DIFs */
213  for (j = 80; j < 80 * 3; j += 80) {
214  for (k = 6; k < 6 * 8; k += 8)
215  dv_write_pack(dv_timecode, c, &buf[j+k]);
216 
217  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 ? */
218  dv_write_pack(dv_video_recdate, c, &buf[j+14]);
219  dv_write_pack(dv_video_rectime, c, &buf[j+22]);
220  dv_write_pack(dv_video_recdate, c, &buf[j+38]);
221  dv_write_pack(dv_video_rectime, c, &buf[j+46]);
222  }
223  }
224 
225  /* DV VAUX: 4th, 5th and 6th 3DIFs */
226  for (j = 80*3 + 3; j < 80*6; j += 80) {
227  dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
228  dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
229  dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
230  dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
231  }
232  }
233 }
234 
235 /*
236  * The following 3 functions constitute our interface to the world
237  */
238 
240  uint8_t* data, int data_size, uint8_t** frame)
241 {
242  int i, reqasize;
243 
244  *frame = &c->frame_buf[0];
245  reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
246 
247  switch (st->codec->codec_type) {
248  case AVMEDIA_TYPE_VIDEO:
249  /* FIXME: we have to have more sensible approach than this one */
250  if (c->has_video)
251  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
252 
253  memcpy(*frame, data, c->sys->frame_size);
254  c->has_video = 1;
255  break;
256  case AVMEDIA_TYPE_AUDIO:
257  for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
258 
259  /* FIXME: we have to have more sensible approach than this one */
260  if (av_fifo_size(c->audio_data[i]) + data_size >= 100*MAX_AUDIO_FRAME_SIZE)
261  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
262  av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);
263 
264  /* Let us see if we've got enough audio for one DV frame. */
265  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
266 
267  break;
268  default:
269  break;
270  }
271 
272  /* Let us see if we have enough data to construct one DV frame. */
273  if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
274  dv_inject_metadata(c, *frame);
275  c->has_audio = 0;
276  for (i=0; i < c->n_ast; i++) {
277  dv_inject_audio(c, i, *frame);
278  av_fifo_drain(c->audio_data[i], reqasize);
279  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
280  }
281 
282  c->has_video = 0;
283 
284  c->frames++;
285 
286  return c->sys->frame_size;
287  }
288 
289  return 0;
290 }
291 
293 {
294  DVMuxContext *c = s->priv_data;
295  AVStream *vst = NULL;
297  int i;
298 
299  /* we support at most 1 video and 2 audio streams */
300  if (s->nb_streams > 3)
301  return NULL;
302 
303  c->n_ast = 0;
304  c->ast[0] = c->ast[1] = NULL;
305 
306  /* We have to sort out where audio and where video stream is */
307  for (i=0; i<s->nb_streams; i++) {
308  switch (s->streams[i]->codec->codec_type) {
309  case AVMEDIA_TYPE_VIDEO:
310  if (vst) return NULL;
311  vst = s->streams[i];
312  break;
313  case AVMEDIA_TYPE_AUDIO:
314  if (c->n_ast > 1) return NULL;
315  c->ast[c->n_ast++] = s->streams[i];
316  break;
317  default:
318  goto bail_out;
319  }
320  }
321 
322  /* Some checks -- DV format is very picky about its incoming streams */
323  if (!vst || vst->codec->codec_id != AV_CODEC_ID_DVVIDEO)
324  goto bail_out;
325  for (i=0; i<c->n_ast; i++) {
326  if (c->ast[i] && (c->ast[i]->codec->codec_id != AV_CODEC_ID_PCM_S16LE ||
327  c->ast[i]->codec->sample_rate != 48000 ||
328  c->ast[i]->codec->channels != 2))
329  goto bail_out;
330  }
331  c->sys = avpriv_dv_codec_profile(vst->codec);
332  if (!c->sys)
333  goto bail_out;
334 
335  if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
336  /* only 1 stereo pair is allowed in 25Mbps mode */
337  goto bail_out;
338  }
339 
340  /* Ok, everything seems to be in working order */
341  c->frames = 0;
342  c->has_audio = 0;
343  c->has_video = 0;
344  if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
346 
347  for (i=0; i < c->n_ast; i++) {
348  if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc(100*MAX_AUDIO_FRAME_SIZE))) {
349  while (i > 0) {
350  i--;
351  av_fifo_free(c->audio_data[i]);
352  }
353  goto bail_out;
354  }
355  }
356 
357  return c;
358 
359 bail_out:
360  return NULL;
361 }
362 
364 {
365  int i;
366  for (i=0; i < c->n_ast; i++)
367  av_fifo_free(c->audio_data[i]);
368 }
369 
371 {
372  if (!dv_init_mux(s)) {
373  av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
374  "Make sure that you supply exactly two streams:\n"
375  " video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
376  " (50Mbps allows an optional second audio stream)\n");
377  return -1;
378  }
379  return 0;
380 }
381 
382 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
383 {
384  uint8_t* frame;
385  int fsize;
386 
387  fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],
388  pkt->data, pkt->size, &frame);
389  if (fsize > 0) {
390  avio_write(s->pb, frame, fsize);
391  avio_flush(s->pb);
392  }
393  return 0;
394 }
395 
396 /*
397  * We might end up with some extra A/V data without matching counterpart.
398  * E.g. video data without enough audio to write the complete frame.
399  * Currently we simply drop the last frame. I don't know whether this
400  * is the best strategy of all
401  */
402 static int dv_write_trailer(struct AVFormatContext *s)
403 {
405  return 0;
406 }
407 
409  .name = "dv",
410  .long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
411  .extensions = "dv",
412  .priv_data_size = sizeof(DVMuxContext),
413  .audio_codec = AV_CODEC_ID_PCM_S16LE,
414  .video_codec = AV_CODEC_ID_DVVIDEO,
418 };