xmv.c
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1 /*
2  * Microsoft XMV demuxer
3  * Copyright (c) 2011 Sven Hesse <drmccoy@drmccoy.de>
4  * Copyright (c) 2011 Matthew Hoops <clone2727@gmail.com>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
28 #include <stdint.h>
29 
30 #include "libavutil/intreadwrite.h"
31 
32 #include "avformat.h"
33 #include "internal.h"
34 #include "riff.h"
35 
36 #define XMV_MIN_HEADER_SIZE 36
37 
38 #define XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT 1
39 #define XMV_AUDIO_ADPCM51_FRONTCENTERLOW 2
40 #define XMV_AUDIO_ADPCM51_REARLEFTRIGHT 4
41 
42 #define XMV_AUDIO_ADPCM51 (XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT | \
43  XMV_AUDIO_ADPCM51_FRONTCENTERLOW | \
44  XMV_AUDIO_ADPCM51_REARLEFTRIGHT)
45 
46 typedef struct XMVAudioTrack {
47  uint16_t compression;
48  uint16_t channels;
49  uint32_t sample_rate;
50  uint16_t bits_per_sample;
51  uint32_t bit_rate;
52  uint16_t flags;
53  uint16_t block_align;
54  uint16_t block_samples;
55 
58 
59 typedef struct XMVVideoPacket {
60  /* The decoder stream index for this video packet. */
62 
63  uint32_t data_size;
64  uint32_t data_offset;
65 
66  uint32_t current_frame;
67  uint32_t frame_count;
68 
69  /* Does the video packet contain extra data? */
71 
72  /* Extra data */
73  uint8_t extradata[4];
74 
75  int64_t last_pts;
76  int64_t pts;
78 
79 typedef struct XMVAudioPacket {
80  /* The decoder stream index for this audio packet. */
82 
83  /* The audio track this packet encodes. */
85 
86  uint32_t data_size;
87  uint32_t data_offset;
88 
89  uint32_t frame_size;
90 
91  uint32_t block_count;
93 
94 typedef struct XMVDemuxContext {
96 
98 
99  uint32_t this_packet_size;
101 
104 
105  uint16_t current_stream;
106  uint16_t stream_count;
107 
111 
112 static int xmv_probe(AVProbeData *p)
113 {
114  uint32_t file_version;
115 
116  if (p->buf_size < XMV_MIN_HEADER_SIZE)
117  return 0;
118 
119  file_version = AV_RL32(p->buf + 16);
120  if ((file_version == 0) || (file_version > 4))
121  return 0;
122 
123  if (!memcmp(p->buf + 12, "xobX", 4))
124  return AVPROBE_SCORE_MAX;
125 
126  return 0;
127 }
128 
130  AVFormatParameters *ap)
131 {
132  XMVDemuxContext *xmv = s->priv_data;
133  AVIOContext *pb = s->pb;
134  AVStream *vst = NULL;
135 
136  uint32_t file_version;
137  uint32_t this_packet_size;
138  uint16_t audio_track;
139 
140  avio_skip(pb, 4); /* Next packet size */
141 
142  this_packet_size = avio_rl32(pb);
143 
144  avio_skip(pb, 4); /* Max packet size */
145  avio_skip(pb, 4); /* "xobX" */
146 
147  file_version = avio_rl32(pb);
148  if ((file_version != 4) && (file_version != 2))
149  av_log_ask_for_sample(s, "Found uncommon version %d\n", file_version);
150 
151 
152  /* Video track */
153 
154  vst = avformat_new_stream(s, NULL);
155  if (!vst)
156  return AVERROR(ENOMEM);
157 
158  avpriv_set_pts_info(vst, 32, 1, 1000);
159 
161  vst->codec->codec_id = CODEC_ID_WMV2;
162  vst->codec->codec_tag = MKBETAG('W', 'M', 'V', '2');
163  vst->codec->width = avio_rl32(pb);
164  vst->codec->height = avio_rl32(pb);
165 
166  vst->duration = avio_rl32(pb);
167 
168  xmv->video.stream_index = vst->index;
169 
170  /* Audio tracks */
171 
172  xmv->audio_track_count = avio_rl16(pb);
173 
174  avio_skip(pb, 2); /* Unknown (padding?) */
175 
176  xmv->audio_tracks = av_malloc(xmv->audio_track_count * sizeof(XMVAudioTrack));
177  if (!xmv->audio_tracks)
178  return AVERROR(ENOMEM);
179 
180  xmv->audio = av_malloc(xmv->audio_track_count * sizeof(XMVAudioPacket));
181  if (!xmv->audio)
182  return AVERROR(ENOMEM);
183 
184  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
185  XMVAudioTrack *track = &xmv->audio_tracks[audio_track];
186  XMVAudioPacket *packet = &xmv->audio [audio_track];
187  AVStream *ast = NULL;
188 
189  track->compression = avio_rl16(pb);
190  track->channels = avio_rl16(pb);
191  track->sample_rate = avio_rl32(pb);
192  track->bits_per_sample = avio_rl16(pb);
193  track->flags = avio_rl16(pb);
194 
195  track->bit_rate = track->bits_per_sample *
196  track->sample_rate *
197  track->channels;
198  track->block_align = 36 * track->channels;
199  track->block_samples = 64;
200  track->codec_id = ff_wav_codec_get_id(track->compression,
201  track->bits_per_sample);
202 
203  packet->track = track;
204  packet->stream_index = -1;
205 
206  packet->frame_size = 0;
207  packet->block_count = 0;
208 
209  /* TODO: ADPCM'd 5.1 sound is encoded in three separate streams.
210  * Those need to be interleaved to a proper 5.1 stream. */
211  if (track->flags & XMV_AUDIO_ADPCM51)
212  av_log(s, AV_LOG_WARNING, "Unsupported 5.1 ADPCM audio stream "
213  "(0x%04X)\n", track->flags);
214 
215  ast = avformat_new_stream(s, NULL);
216  if (!ast)
217  return AVERROR(ENOMEM);
218 
220  ast->codec->codec_id = track->codec_id;
221  ast->codec->codec_tag = track->compression;
222  ast->codec->channels = track->channels;
223  ast->codec->sample_rate = track->sample_rate;
225  ast->codec->bit_rate = track->bit_rate;
226  ast->codec->block_align = 36 * track->channels;
227 
228  avpriv_set_pts_info(ast, 32, track->block_samples, track->sample_rate);
229 
230  packet->stream_index = ast->index;
231 
232  ast->duration = vst->duration;
233  }
234 
235 
238  xmv->next_packet_offset = avio_tell(pb);
239  xmv->next_packet_size = this_packet_size - xmv->next_packet_offset;
240  xmv->stream_count = xmv->audio_track_count + 1;
241 
242  return 0;
243 }
244 
245 static void xmv_read_extradata(uint8_t *extradata, AVIOContext *pb)
246 {
247  /* Read the XMV extradata */
248 
249  uint32_t data = avio_rl32(pb);
250 
251  int mspel_bit = !!(data & 0x01);
252  int loop_filter = !!(data & 0x02);
253  int abt_flag = !!(data & 0x04);
254  int j_type_bit = !!(data & 0x08);
255  int top_left_mv_flag = !!(data & 0x10);
256  int per_mb_rl_bit = !!(data & 0x20);
257  int slice_count = (data >> 6) & 7;
258 
259  /* Write it back as standard WMV2 extradata */
260 
261  data = 0;
262 
263  data |= mspel_bit << 15;
264  data |= loop_filter << 14;
265  data |= abt_flag << 13;
266  data |= j_type_bit << 12;
267  data |= top_left_mv_flag << 11;
268  data |= per_mb_rl_bit << 10;
269  data |= slice_count << 7;
270 
271  AV_WB32(extradata, data);
272 }
273 
275 {
276  XMVDemuxContext *xmv = s->priv_data;
277  AVIOContext *pb = s->pb;
278 
279  uint8_t data[8];
280  uint16_t audio_track;
281  uint32_t data_offset;
282 
283  /* Next packet size */
284  xmv->next_packet_size = avio_rl32(pb);
285 
286  /* Packet video header */
287 
288  if (avio_read(pb, data, 8) != 8)
289  return AVERROR(EIO);
290 
291  xmv->video.data_size = AV_RL32(data) & 0x007FFFFF;
292 
293  xmv->video.current_frame = 0;
294  xmv->video.frame_count = (AV_RL32(data) >> 23) & 0xFF;
295 
296  xmv->video.has_extradata = (data[3] & 0x80) != 0;
297 
298  /* Adding the audio data sizes and the video data size keeps you 4 bytes
299  * short for every audio track. But as playing around with XMV files with
300  * ADPCM audio showed, taking the extra 4 bytes from the audio data gives
301  * you either completely distorted audio or click (when skipping the
302  * remaining 68 bytes of the ADPCM block). Substracting 4 bytes for every
303  * audio track from the video data works at least for the audio. Probably
304  * some alignment thing?
305  * The video data has (always?) lots of padding, so it should work out...
306  */
307  xmv->video.data_size -= xmv->audio_track_count * 4;
308 
309  xmv->current_stream = 0;
310  if (!xmv->video.frame_count) {
311  xmv->video.frame_count = 1;
312  xmv->current_stream = 1;
313  }
314 
315  /* Packet audio header */
316 
317  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
318  XMVAudioPacket *packet = &xmv->audio[audio_track];
319 
320  if (avio_read(pb, data, 4) != 4)
321  return AVERROR(EIO);
322 
323  packet->data_size = AV_RL32(data) & 0x007FFFFF;
324  if ((packet->data_size == 0) && (audio_track != 0))
325  /* This happens when I create an XMV with several identical audio
326  * streams. From the size calculations, duplicating the previous
327  * stream's size works out, but the track data itself is silent.
328  * Maybe this should also redirect the offset to the previous track?
329  */
330  packet->data_size = xmv->audio[audio_track - 1].data_size;
331 
333  packet->frame_size = packet->data_size / xmv->video.frame_count;
334  packet->frame_size -= packet->frame_size % packet->track->block_align;
335  }
336 
337  /* Packet data offsets */
338 
339  data_offset = avio_tell(pb);
340 
341  xmv->video.data_offset = data_offset;
342  data_offset += xmv->video.data_size;
343 
344  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
345  xmv->audio[audio_track].data_offset = data_offset;
346  data_offset += xmv->audio[audio_track].data_size;
347  }
348 
349  /* Video frames header */
350 
351  /* Read new video extra data */
352  if (xmv->video.data_size > 0) {
353  if (xmv->video.has_extradata) {
355 
356  xmv->video.data_size -= 4;
357  xmv->video.data_offset += 4;
358 
359  if (xmv->video.stream_index >= 0) {
360  AVStream *vst = s->streams[xmv->video.stream_index];
361 
362  assert(xmv->video.stream_index < s->nb_streams);
363 
364  if (vst->codec->extradata_size < 4) {
365  av_free(vst->codec->extradata);
366 
367  vst->codec->extradata =
369  vst->codec->extradata_size = 4;
370  }
371 
372  memcpy(vst->codec->extradata, xmv->video.extradata, 4);
373  }
374  }
375  }
376 
377  return 0;
378 }
379 
381 {
382  XMVDemuxContext *xmv = s->priv_data;
383  AVIOContext *pb = s->pb;
384  int result;
385 
386  /* Seek to it */
388  if (avio_seek(pb, xmv->this_packet_offset, SEEK_SET) != xmv->this_packet_offset)
389  return AVERROR(EIO);
390 
391  /* Update the size */
393  if (xmv->this_packet_size < (12 + xmv->audio_track_count * 4))
394  return AVERROR(EIO);
395 
396  /* Process the header */
397  result = xmv_process_packet_header(s);
398  if (result)
399  return result;
400 
401  /* Update the offset */
403 
404  return 0;
405 }
406 
408  AVPacket *pkt, uint32_t stream)
409 {
410  XMVDemuxContext *xmv = s->priv_data;
411  AVIOContext *pb = s->pb;
412  XMVAudioPacket *audio = &xmv->audio[stream];
413 
414  uint32_t data_size;
415  uint32_t block_count;
416  int result;
417 
418  /* Seek to it */
419  if (avio_seek(pb, audio->data_offset, SEEK_SET) != audio->data_offset)
420  return AVERROR(EIO);
421 
422  if ((xmv->video.current_frame + 1) < xmv->video.frame_count)
423  /* Not the last frame, get at most frame_size bytes. */
424  data_size = FFMIN(audio->frame_size, audio->data_size);
425  else
426  /* Last frame, get the rest. */
427  data_size = audio->data_size;
428 
429  /* Read the packet */
430  result = av_get_packet(pb, pkt, data_size);
431  if (result <= 0)
432  return result;
433 
434  pkt->stream_index = audio->stream_index;
435 
436  /* Calculate the PTS */
437 
438  block_count = data_size / audio->track->block_align;
439 
440  pkt->duration = block_count;
441  pkt->pts = audio->block_count;
442  pkt->dts = AV_NOPTS_VALUE;
443 
444  audio->block_count += block_count;
445 
446  /* Advance offset */
447  audio->data_size -= data_size;
448  audio->data_offset += data_size;
449 
450  return 0;
451 }
452 
454  AVPacket *pkt)
455 {
456  XMVDemuxContext *xmv = s->priv_data;
457  AVIOContext *pb = s->pb;
458  XMVVideoPacket *video = &xmv->video;
459 
460  int result;
461  uint32_t frame_header;
462  uint32_t frame_size, frame_timestamp;
463  uint32_t i;
464 
465  /* Seek to it */
466  if (avio_seek(pb, video->data_offset, SEEK_SET) != video->data_offset)
467  return AVERROR(EIO);
468 
469  /* Read the frame header */
470  frame_header = avio_rl32(pb);
471 
472  frame_size = (frame_header & 0x1FFFF) * 4 + 4;
473  frame_timestamp = (frame_header >> 17);
474 
475  if ((frame_size + 4) > video->data_size)
476  return AVERROR(EIO);
477 
478  /* Create the packet */
479  result = av_new_packet(pkt, frame_size);
480  if (result)
481  return result;
482 
483  /* Contrary to normal WMV2 video, the bit stream in XMV's
484  * WMV2 is little-endian.
485  * TODO: This manual swap is of course suboptimal.
486  */
487  for (i = 0; i < frame_size; i += 4)
488  AV_WB32(pkt->data + i, avio_rl32(pb));
489 
490  pkt->stream_index = video->stream_index;
491 
492  /* Calculate the PTS */
493 
494  video->last_pts = frame_timestamp + video->pts;
495 
496  pkt->duration = 0;
497  pkt->pts = video->last_pts;
498  pkt->dts = AV_NOPTS_VALUE;
499 
500  video->pts += frame_timestamp;
501 
502  /* Keyframe? */
503  pkt->flags = (pkt->data[0] & 0x80) ? 0 : AV_PKT_FLAG_KEY;
504 
505  /* Advance offset */
506  video->data_size -= frame_size + 4;
507  video->data_offset += frame_size + 4;
508 
509  return 0;
510 }
511 
513  AVPacket *pkt)
514 {
515  XMVDemuxContext *xmv = s->priv_data;
516  int result;
517 
518  if (xmv->video.current_frame == xmv->video.frame_count) {
519  /* No frames left in this packet, so we fetch a new one */
520 
521  result = xmv_fetch_new_packet(s);
522  if (result)
523  return result;
524  }
525 
526  if (xmv->current_stream == 0) {
527  /* Fetch a video frame */
528 
529  result = xmv_fetch_video_packet(s, pkt);
530  if (result)
531  return result;
532 
533  } else {
534  /* Fetch an audio frame */
535 
536  result = xmv_fetch_audio_packet(s, pkt, xmv->current_stream - 1);
537  if (result)
538  return result;
539  }
540 
541  /* Increase our counters */
542  if (++xmv->current_stream >= xmv->stream_count) {
543  xmv->current_stream = 0;
544  xmv->video.current_frame += 1;
545  }
546 
547  return 0;
548 }
549 
551 {
552  XMVDemuxContext *xmv = s->priv_data;
553 
554  av_free(xmv->audio);
555  av_free(xmv->audio_tracks);
556 
557  return 0;
558 }
559 
561  .name = "xmv",
562  .long_name = NULL_IF_CONFIG_SMALL("Microsoft XMV"),
563  .priv_data_size = sizeof(XMVDemuxContext),
568 };