FFmpeg: libavformat/dvenc.c Source File

FFmpeg
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/dvdata.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 {
47   AVClass *av_class;
48   const DVprofile* 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 DVprofile* sys, int frame)
76 {
77  return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
78  sizeof(sys->audio_samples_dist[0]))];
79 }
80 
81  static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
82 {
83  struct tm tc;
84  time_t ct;
85  uint32_t timecode;
86  va_list ap;
87 
88  buf[0] = (uint8_t)pack_id;
89  switch (pack_id) {
90  case dv_timecode:
91  timecode = av_timecode_get_smpte_from_framenum(&c->tc, c->frames);
92  timecode |= 1<<23 | 1<<15 | 1<<7 | 1<<6; // biphase and binary group flags
93  AV_WB32(buf + 1, timecode);
94  break;
95  case dv_audio_source: /* AAUX source pack */
96  va_start(ap, buf);
97  buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
98  (1 << 6) | /* reserved -- always 1 */
99  (dv_audio_frame_size(c->sys, c->frames) -
100  c->sys->audio_min_samples[0]);
101  /* # of samples */
102  buf[2] = (0 << 7) | /* multi-stereo */
103  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
104  (0 << 4) | /* pair bit: 0 -- one pair of channels */
105  !!va_arg(ap, int); /* audio mode */
106  buf[3] = (1 << 7) | /* res */
107  (1 << 6) | /* multi-language flag */
108  (c->sys->dsf << 5) | /* system: 60fields/50fields */
109  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
110  buf[4] = (1 << 7) | /* emphasis: 1 -- off */
111  (0 << 6) | /* emphasis time constant: 0 -- reserved */
112  (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
113  0; /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
114  va_end(ap);
115  break;
116  case dv_audio_control:
117  buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
118  (1 << 4) | /* input source: 1 -- digital input */
119  (3 << 2) | /* compression: 3 -- no information */
120  0; /* misc. info/SMPTE emphasis off */
121  buf[2] = (1 << 7) | /* recording start point: 1 -- no */
122  (1 << 6) | /* recording end point: 1 -- no */
123  (1 << 3) | /* recording mode: 1 -- original */
124  7;
125  buf[3] = (1 << 7) | /* direction: 1 -- forward */
126  (c->sys->pix_fmt == AV_PIX_FMT_YUV420P ? 0x20 : /* speed */
127  c->sys->ltc_divisor * 4);
128  buf[4] = (1 << 7) | /* reserved -- always 1 */
129  0x7f; /* genre category */
130  break;
131  case dv_audio_recdate:
132  case dv_video_recdate: /* VAUX recording date */
133  ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
134  c->sys->time_base.den, AV_ROUND_DOWN);
135  ff_brktimegm(ct, &tc);
136  buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
137  /* 0xff is very likely to be "unknown" */
138  buf[2] = (3 << 6) | /* reserved -- always 1 */
139  ((tc.tm_mday / 10) << 4) | /* Tens of day */
140  (tc.tm_mday % 10); /* Units of day */
141  buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
142  ((tc.tm_mon / 10) << 4) | /* Tens of month */
143  (tc.tm_mon % 10); /* Units of month */
144  buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
145  (tc.tm_year % 10); /* Units of year */
146  break;
147  case dv_audio_rectime: /* AAUX recording time */
148  case dv_video_rectime: /* VAUX recording time */
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] = (3 << 6) | /* reserved -- always 1 */
153  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
154  buf[2] = (1 << 7) | /* reserved -- always 1 */
155  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
156  (tc.tm_sec % 10); /* Units of seconds */
157  buf[3] = (1 << 7) | /* reserved -- always 1 */
158  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
159  (tc.tm_min % 10); /* Units of minutes */
160  buf[4] = (3 << 6) | /* reserved -- always 1 */
161  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
162  (tc.tm_hour % 10); /* Units of hours */
163  break;
164  default:
165  buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
166  }
167  return 5;
168 }
169 
170  static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
171 {
172  int i, j, d, of, size;
173  size = 4 * dv_audio_frame_size(c->sys, c->frames);
174  frame_ptr += channel * c->sys->difseg_size * 150 * 80;
175  for (i = 0; i < c->sys->difseg_size; i++) {
176  frame_ptr += 6 * 80; /* skip DIF segment header */
177  for (j = 0; j < 9; j++) {
178  dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
179  for (d = 8; d < 80; d+=2) {
180  of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
181  if (of*2 >= size)
182  continue;
183 
184  frame_ptr[d] = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
185  frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2); // that DV is a big-endian PCM
186  }
187  frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
188  }
189  }
190 }
191 
192  static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
193 {
194  int j, k;
195  uint8_t* buf;
196 
197  for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
198  /* DV subcode: 2nd and 3d DIFs */
199  for (j = 80; j < 80 * 3; j += 80) {
200  for (k = 6; k < 6 * 8; k += 8)
201  dv_write_pack(dv_timecode, c, &buf[j+k]);
202 
203  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 ? */
204  dv_write_pack(dv_video_recdate, c, &buf[j+14]);
205  dv_write_pack(dv_video_rectime, c, &buf[j+22]);
206  dv_write_pack(dv_video_recdate, c, &buf[j+38]);
207  dv_write_pack(dv_video_rectime, c, &buf[j+46]);
208  }
209  }
210 
211  /* DV VAUX: 4th, 5th and 6th 3DIFs */
212  for (j = 80*3 + 3; j < 80*6; j += 80) {
213  dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
214  dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
215  dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
216  dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
217  }
218  }
219 }
220 
221 /*
222  * The following 3 functions constitute our interface to the world
223  */
224 
225  static int dv_assemble_frame(DVMuxContext *c, AVStream* st,
226  uint8_t* data, int data_size, uint8_t** frame)
227 {
228  int i, reqasize;
229 
230  *frame = &c->frame_buf[0];
231  reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
232 
233  switch (st->codec->codec_type) {
234  case AVMEDIA_TYPE_VIDEO:
235  /* FIXME: we have to have more sensible approach than this one */
236  if (c->has_video)
237  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
238 
239  memcpy(*frame, data, c->sys->frame_size);
240  c->has_video = 1;
241  break;
242  case AVMEDIA_TYPE_AUDIO:
243  for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
244 
245  /* FIXME: we have to have more sensible approach than this one */
246  if (av_fifo_size(c->audio_data[i]) + data_size >= 100*MAX_AUDIO_FRAME_SIZE)
247  av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
248  av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);
249 
250  /* Let us see if we've got enough audio for one DV frame. */
251  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
252 
253  break;
254  default:
255  break;
256  }
257 
258  /* Let us see if we have enough data to construct one DV frame. */
259  if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
260  dv_inject_metadata(c, *frame);
261  c->has_audio = 0;
262  for (i=0; i < c->n_ast; i++) {
263  dv_inject_audio(c, i, *frame);
264  av_fifo_drain(c->audio_data[i], reqasize);
265  c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
266  }
267 
268  c->has_video = 0;
269 
270  c->frames++;
271 
272  return c->sys->frame_size;
273  }
274 
275  return 0;
276 }
277 
278  static DVMuxContext* dv_init_mux(AVFormatContext* s)
279 {
280  DVMuxContext *c = s->priv_data;
281  AVStream *vst = NULL;
282  AVDictionaryEntry *t;
283  int i;
284 
285  /* we support at most 1 video and 2 audio streams */
286  if (s->nb_streams > 3)
287  return NULL;
288 
289  c->n_ast = 0;
290  c->ast[0] = c->ast[1] = NULL;
291 
292  /* We have to sort out where audio and where video stream is */
293  for (i=0; i<s->nb_streams; i++) {
294  switch (s->streams[i]->codec->codec_type) {
295  case AVMEDIA_TYPE_VIDEO:
296  if (vst) return NULL;
297  vst = s->streams[i];
298  break;
299  case AVMEDIA_TYPE_AUDIO:
300  if (c->n_ast > 1) return NULL;
301  c->ast[c->n_ast++] = s->streams[i];
302  break;
303  default:
304  goto bail_out;
305  }
306  }
307 
308  /* Some checks -- DV format is very picky about its incoming streams */
309  if (!vst || vst->codec->codec_id != AV_CODEC_ID_DVVIDEO)
310  goto bail_out;
311  for (i=0; i<c->n_ast; i++) {
312  if (c->ast[i] && (c->ast[i]->codec->codec_id != AV_CODEC_ID_PCM_S16LE ||
313  c->ast[i]->codec->sample_rate != 48000 ||
314  c->ast[i]->codec->channels != 2))
315  goto bail_out;
316  }
317  c->sys = avpriv_dv_codec_profile(vst->codec);
318  if (!c->sys)
319  goto bail_out;
320 
321  if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
322  /* only 1 stereo pair is allowed in 25Mbps mode */
323  goto bail_out;
324  }
325 
326  /* Ok, everything seems to be in working order */
327  c->frames = 0;
328  c->has_audio = 0;
329  c->has_video = 0;
330  if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
331  c->start_time = ff_iso8601_to_unix_time(t->value);
332 
333  for (i=0; i < c->n_ast; i++) {
334  if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc(100*MAX_AUDIO_FRAME_SIZE))) {
335  while (i > 0) {
336  i--;
337  av_fifo_free(c->audio_data[i]);
338  }
339  goto bail_out;
340  }
341  }
342 
343  return c;
344 
345 bail_out:
346  return NULL;
347 }
348 
349  static void dv_delete_mux(DVMuxContext *c)
350 {
351  int i;
352  for (i=0; i < c->n_ast; i++)
353  av_fifo_free(c->audio_data[i]);
354 }
355 
356  static int dv_write_header(AVFormatContext *s)
357 {
358  AVRational rate;
359  DVMuxContext *dvc = s->priv_data;
360  AVDictionaryEntry *tcr = av_dict_get(s->metadata, "timecode", NULL, 0);
361 
362  if (!dv_init_mux(s)) {
363  av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
364  "Make sure that you supply exactly two streams:\n"
365  " video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
366  " (50Mbps allows an optional second audio stream)\n");
367  return -1;
368  }
369  rate.num = dvc->sys->ltc_divisor;
370  rate.den = 1;
371  if (!tcr) { // no global timecode, look into the streams
372  int i;
373  for (i = 0; i < s->nb_streams; i++) {
374  tcr = av_dict_get(s->streams[i]->metadata, "timecode", NULL, 0);
375  if (tcr)
376  break;
377  }
378  }
379  if (tcr && av_timecode_init_from_string(&dvc->tc, rate, tcr->value, s) >= 0)
380  return 0;
381  return av_timecode_init(&dvc->tc, rate, 0, 0, s);
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  }
394  return 0;
395 }
396 
397 /*
398  * We might end up with some extra A/V data without matching counterpart.
399  * E.g. video data without enough audio to write the complete frame.
400  * Currently we simply drop the last frame. I don't know whether this
401  * is the best strategy of all
402  */
403  static int dv_write_trailer(struct AVFormatContext *s)
404 {
405  dv_delete_mux(s->priv_data);
406  return 0;
407 }
408 
409  AVOutputFormat ff_dv_muxer = {
410  .name = "dv",
411  .long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
412  .extensions = "dv",
413  .priv_data_size = sizeof(DVMuxContext),
414  .audio_codec = AV_CODEC_ID_PCM_S16LE,
415  .video_codec = AV_CODEC_ID_DVVIDEO,
416  .write_header = dv_write_header,
417  .write_packet = dv_write_packet,
418  .write_trailer = dv_write_trailer,
419 };
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