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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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Microsoft XMV demuxer
26  */
27 
28 #include <stdint.h>
29 
30 #include "libavutil/intreadwrite.h"
31 
32 #include "avformat.h"
33 #include "internal.h"
34 #include "riff.h"
35 #include "libavutil/avassert.h"
36 
37 /** The min size of an XMV header. */
38 #define XMV_MIN_HEADER_SIZE 36
39 
40 /** Audio flag: ADPCM'd 5.1 stream, front left / right channels */
41 #define XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT 1
42 /** Audio flag: ADPCM'd 5.1 stream, front center / low frequency channels */
43 #define XMV_AUDIO_ADPCM51_FRONTCENTERLOW 2
44 /** Audio flag: ADPCM'd 5.1 stream, rear left / right channels */
45 #define XMV_AUDIO_ADPCM51_REARLEFTRIGHT 4
46 
47 /** Audio flag: Any of the ADPCM'd 5.1 stream flags. */
48 #define XMV_AUDIO_ADPCM51 (XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT | \
49  XMV_AUDIO_ADPCM51_FRONTCENTERLOW | \
50  XMV_AUDIO_ADPCM51_REARLEFTRIGHT)
51 
52 #define XMV_BLOCK_ALIGN_SIZE 36
53 
54 /** A video packet with an XMV file. */
55 typedef struct XMVVideoPacket {
56  int stream_index; ///< The decoder stream index for this video packet.
57 
58  uint32_t data_size; ///< The size of the remaining video data.
59  uint64_t data_offset; ///< The offset of the video data within the file.
60 
61  uint32_t current_frame; ///< The current frame within this video packet.
62  uint32_t frame_count; ///< The amount of frames within this video packet.
63 
64  int has_extradata; ///< Does the video packet contain extra data?
65  uint8_t extradata[4]; ///< The extra data
66 
67  int64_t last_pts; ///< PTS of the last video frame.
68  int64_t pts; ///< PTS of the most current video frame.
70 
71 /** An audio packet with an XMV file. */
72 typedef struct XMVAudioPacket {
73  int stream_index; ///< The decoder stream index for this audio packet.
74 
75  /* Stream format properties. */
76  uint16_t compression; ///< The type of compression.
77  uint16_t channels; ///< Number of channels.
78  uint32_t sample_rate; ///< Sampling rate.
79  uint16_t bits_per_sample; ///< Bits per compressed sample.
80  uint32_t bit_rate; ///< Bits of compressed data per second.
81  uint16_t flags; ///< Flags
82  unsigned block_align; ///< Bytes per compressed block.
83  uint16_t block_samples; ///< Decompressed samples per compressed block.
84 
85  enum AVCodecID codec_id; ///< The codec ID of the compression scheme.
86 
87  uint32_t data_size; ///< The size of the remaining audio data.
88  uint64_t data_offset; ///< The offset of the audio data within the file.
89 
90  uint32_t frame_size; ///< Number of bytes to put into an audio frame.
91 
92  uint64_t block_count; ///< Running counter of decompressed audio block.
94 
95 /** Context for demuxing an XMV file. */
96 typedef struct XMVDemuxContext {
97  uint16_t audio_track_count; ///< Number of audio track in this file.
98 
99  uint32_t this_packet_size; ///< Size of the current packet.
100  uint32_t next_packet_size; ///< Size of the next packet.
101 
102  uint64_t this_packet_offset; ///< Offset of the current packet.
103  uint64_t next_packet_offset; ///< Offset of the next packet.
104 
105  uint16_t current_stream; ///< The index of the stream currently handling.
106  uint16_t stream_count; ///< The number of streams in this file.
107 
108  XMVVideoPacket video; ///< The video packet contained in each packet.
109  XMVAudioPacket *audio; ///< The audio packets contained in each packet.
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 {
131  XMVDemuxContext *xmv = s->priv_data;
132 
133  av_freep(&xmv->audio);
134 
135  return 0;
136 }
137 
139 {
140  XMVDemuxContext *xmv = s->priv_data;
141  AVIOContext *pb = s->pb;
142  AVStream *vst = NULL;
143 
144  uint32_t file_version;
145  uint32_t this_packet_size;
146  uint16_t audio_track;
147  int ret;
148 
149  avio_skip(pb, 4); /* Next packet size */
150 
151  this_packet_size = avio_rl32(pb);
152 
153  avio_skip(pb, 4); /* Max packet size */
154  avio_skip(pb, 4); /* "xobX" */
155 
156  file_version = avio_rl32(pb);
157  if ((file_version != 4) && (file_version != 2))
158  avpriv_request_sample(s, "Uncommon version %d", file_version);
159 
160 
161  /* Video track */
162 
163  vst = avformat_new_stream(s, NULL);
164  if (!vst)
165  return AVERROR(ENOMEM);
166 
167  avpriv_set_pts_info(vst, 32, 1, 1000);
168 
171  vst->codec->codec_tag = MKBETAG('W', 'M', 'V', '2');
172  vst->codec->width = avio_rl32(pb);
173  vst->codec->height = avio_rl32(pb);
174 
175  vst->duration = avio_rl32(pb);
176 
177  xmv->video.stream_index = vst->index;
178 
179  /* Audio tracks */
180 
181  xmv->audio_track_count = avio_rl16(pb);
182 
183  avio_skip(pb, 2); /* Unknown (padding?) */
184 
185  xmv->audio = av_malloc(xmv->audio_track_count * sizeof(XMVAudioPacket));
186  if (!xmv->audio) {
187  ret = AVERROR(ENOMEM);
188  goto fail;
189  }
190 
191  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
192  XMVAudioPacket *packet = &xmv->audio[audio_track];
193  AVStream *ast = NULL;
194 
195  packet->compression = avio_rl16(pb);
196  packet->channels = avio_rl16(pb);
197  packet->sample_rate = avio_rl32(pb);
198  packet->bits_per_sample = avio_rl16(pb);
199  packet->flags = avio_rl16(pb);
200 
201  packet->bit_rate = packet->bits_per_sample *
202  packet->sample_rate *
203  packet->channels;
204  packet->block_align = XMV_BLOCK_ALIGN_SIZE * packet->channels;
205  packet->block_samples = 64;
206  packet->codec_id = ff_wav_codec_get_id(packet->compression,
207  packet->bits_per_sample);
208 
209  packet->stream_index = -1;
210 
211  packet->frame_size = 0;
212  packet->block_count = 0;
213 
214  /* TODO: ADPCM'd 5.1 sound is encoded in three separate streams.
215  * Those need to be interleaved to a proper 5.1 stream. */
216  if (packet->flags & XMV_AUDIO_ADPCM51)
217  av_log(s, AV_LOG_WARNING, "Unsupported 5.1 ADPCM audio stream "
218  "(0x%04X)\n", packet->flags);
219 
220  if (!packet->channels || !packet->sample_rate ||
221  packet->channels >= UINT16_MAX / XMV_BLOCK_ALIGN_SIZE) {
222  av_log(s, AV_LOG_ERROR, "Invalid parameters for audio track %d.\n",
223  audio_track);
224  ret = AVERROR_INVALIDDATA;
225  goto fail;
226  }
227 
228  ast = avformat_new_stream(s, NULL);
229  if (!ast) {
230  ret = AVERROR(ENOMEM);
231  goto fail;
232  }
233 
235  ast->codec->codec_id = packet->codec_id;
236  ast->codec->codec_tag = packet->compression;
237  ast->codec->channels = packet->channels;
238  ast->codec->sample_rate = packet->sample_rate;
240  ast->codec->bit_rate = packet->bit_rate;
241  ast->codec->block_align = 36 * packet->channels;
242 
243  avpriv_set_pts_info(ast, 32, packet->block_samples, packet->sample_rate);
244 
245  packet->stream_index = ast->index;
246 
247  ast->duration = vst->duration;
248  }
249 
250 
251  /* Initialize the packet context */
252 
253  xmv->next_packet_offset = avio_tell(pb);
254  xmv->next_packet_size = this_packet_size - xmv->next_packet_offset;
255  xmv->stream_count = xmv->audio_track_count + 1;
256 
257  return 0;
258 
259 fail:
260  xmv_read_close(s);
261  return ret;
262 }
263 
264 static void xmv_read_extradata(uint8_t *extradata, AVIOContext *pb)
265 {
266  /* Read the XMV extradata */
267 
268  uint32_t data = avio_rl32(pb);
269 
270  int mspel_bit = !!(data & 0x01);
271  int loop_filter = !!(data & 0x02);
272  int abt_flag = !!(data & 0x04);
273  int j_type_bit = !!(data & 0x08);
274  int top_left_mv_flag = !!(data & 0x10);
275  int per_mb_rl_bit = !!(data & 0x20);
276  int slice_count = (data >> 6) & 7;
277 
278  /* Write it back as standard WMV2 extradata */
279 
280  data = 0;
281 
282  data |= mspel_bit << 15;
283  data |= loop_filter << 14;
284  data |= abt_flag << 13;
285  data |= j_type_bit << 12;
286  data |= top_left_mv_flag << 11;
287  data |= per_mb_rl_bit << 10;
288  data |= slice_count << 7;
289 
290  AV_WB32(extradata, data);
291 }
292 
294 {
295  XMVDemuxContext *xmv = s->priv_data;
296  AVIOContext *pb = s->pb;
297 
298  uint8_t data[8];
299  uint16_t audio_track;
300  uint64_t data_offset;
301 
302  /* Next packet size */
303  xmv->next_packet_size = avio_rl32(pb);
304 
305  /* Packet video header */
306 
307  if (avio_read(pb, data, 8) != 8)
308  return AVERROR(EIO);
309 
310  xmv->video.data_size = AV_RL32(data) & 0x007FFFFF;
311 
312  xmv->video.current_frame = 0;
313  xmv->video.frame_count = (AV_RL32(data) >> 23) & 0xFF;
314 
315  xmv->video.has_extradata = (data[3] & 0x80) != 0;
316 
317  /* Adding the audio data sizes and the video data size keeps you 4 bytes
318  * short for every audio track. But as playing around with XMV files with
319  * ADPCM audio showed, taking the extra 4 bytes from the audio data gives
320  * you either completely distorted audio or click (when skipping the
321  * remaining 68 bytes of the ADPCM block). Subtracting 4 bytes for every
322  * audio track from the video data works at least for the audio. Probably
323  * some alignment thing?
324  * The video data has (always?) lots of padding, so it should work out...
325  */
326  xmv->video.data_size -= xmv->audio_track_count * 4;
327 
328  xmv->current_stream = 0;
329  if (!xmv->video.frame_count) {
330  xmv->video.frame_count = 1;
331  xmv->current_stream = xmv->stream_count > 1;
332  }
333 
334  /* Packet audio header */
335 
336  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
337  XMVAudioPacket *packet = &xmv->audio[audio_track];
338 
339  if (avio_read(pb, data, 4) != 4)
340  return AVERROR(EIO);
341 
342  packet->data_size = AV_RL32(data) & 0x007FFFFF;
343  if ((packet->data_size == 0) && (audio_track != 0))
344  /* This happens when I create an XMV with several identical audio
345  * streams. From the size calculations, duplicating the previous
346  * stream's size works out, but the track data itself is silent.
347  * Maybe this should also redirect the offset to the previous track?
348  */
349  packet->data_size = xmv->audio[audio_track - 1].data_size;
350 
351  /* Carve up the audio data in frame_count slices */
352  packet->frame_size = packet->data_size / xmv->video.frame_count;
353  packet->frame_size -= packet->frame_size % packet->block_align;
354  }
355 
356  /* Packet data offsets */
357 
358  data_offset = avio_tell(pb);
359 
360  xmv->video.data_offset = data_offset;
361  data_offset += xmv->video.data_size;
362 
363  for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
364  xmv->audio[audio_track].data_offset = data_offset;
365  data_offset += xmv->audio[audio_track].data_size;
366  }
367 
368  /* Video frames header */
369 
370  /* Read new video extra data */
371  if (xmv->video.data_size > 0) {
372  if (xmv->video.has_extradata) {
374 
375  xmv->video.data_size -= 4;
376  xmv->video.data_offset += 4;
377 
378  if (xmv->video.stream_index >= 0) {
379  AVStream *vst = s->streams[xmv->video.stream_index];
380 
382 
383  if (vst->codec->extradata_size < 4) {
384  av_free(vst->codec->extradata);
385 
386  ff_alloc_extradata(vst->codec, 4);
387  }
388 
389  memcpy(vst->codec->extradata, xmv->video.extradata, 4);
390  }
391  }
392  }
393 
394  return 0;
395 }
396 
398 {
399  XMVDemuxContext *xmv = s->priv_data;
400  AVIOContext *pb = s->pb;
401  int result;
402 
403  if (xmv->this_packet_offset == xmv->next_packet_offset)
404  return AVERROR_EOF;
405 
406  /* Seek to it */
408  if (avio_seek(pb, xmv->this_packet_offset, SEEK_SET) != xmv->this_packet_offset)
409  return AVERROR(EIO);
410 
411  /* Update the size */
413  if (xmv->this_packet_size < (12 + xmv->audio_track_count * 4))
414  return AVERROR(EIO);
415 
416  /* Process the header */
417  result = xmv_process_packet_header(s);
418  if (result)
419  return result;
420 
421  /* Update the offset */
423 
424  return 0;
425 }
426 
428  AVPacket *pkt, uint32_t stream)
429 {
430  XMVDemuxContext *xmv = s->priv_data;
431  AVIOContext *pb = s->pb;
432  XMVAudioPacket *audio = &xmv->audio[stream];
433 
434  uint32_t data_size;
435  uint32_t block_count;
436  int result;
437 
438  /* Seek to it */
439  if (avio_seek(pb, audio->data_offset, SEEK_SET) != audio->data_offset)
440  return AVERROR(EIO);
441 
442  if ((xmv->video.current_frame + 1) < xmv->video.frame_count)
443  /* Not the last frame, get at most frame_size bytes. */
444  data_size = FFMIN(audio->frame_size, audio->data_size);
445  else
446  /* Last frame, get the rest. */
447  data_size = audio->data_size;
448 
449  /* Read the packet */
450  result = av_get_packet(pb, pkt, data_size);
451  if (result <= 0)
452  return result;
453 
454  pkt->stream_index = audio->stream_index;
455 
456  /* Calculate the PTS */
457 
458  block_count = data_size / audio->block_align;
459 
460  pkt->duration = block_count;
461  pkt->pts = audio->block_count;
462  pkt->dts = AV_NOPTS_VALUE;
463 
464  audio->block_count += block_count;
465 
466  /* Advance offset */
467  audio->data_size -= data_size;
468  audio->data_offset += data_size;
469 
470  return 0;
471 }
472 
474  AVPacket *pkt)
475 {
476  XMVDemuxContext *xmv = s->priv_data;
477  AVIOContext *pb = s->pb;
478  XMVVideoPacket *video = &xmv->video;
479 
480  int result;
481  uint32_t frame_header;
482  uint32_t frame_size, frame_timestamp;
483  uint8_t *data, *end;
484 
485  /* Seek to it */
486  if (avio_seek(pb, video->data_offset, SEEK_SET) != video->data_offset)
487  return AVERROR(EIO);
488 
489  /* Read the frame header */
490  frame_header = avio_rl32(pb);
491 
492  frame_size = (frame_header & 0x1FFFF) * 4 + 4;
493  frame_timestamp = (frame_header >> 17);
494 
495  if ((frame_size + 4) > video->data_size)
496  return AVERROR(EIO);
497 
498  /* Get the packet data */
499  result = av_get_packet(pb, pkt, frame_size);
500  if (result != frame_size)
501  return result;
502 
503  /* Contrary to normal WMV2 video, the bit stream in XMV's
504  * WMV2 is little-endian.
505  * TODO: This manual swap is of course suboptimal.
506  */
507  for (data = pkt->data, end = pkt->data + frame_size; data < end; data += 4)
508  AV_WB32(data, AV_RL32(data));
509 
510  pkt->stream_index = video->stream_index;
511 
512  /* Calculate the PTS */
513 
514  video->last_pts = frame_timestamp + video->pts;
515 
516  pkt->duration = 0;
517  pkt->pts = video->last_pts;
518  pkt->dts = AV_NOPTS_VALUE;
519 
520  video->pts += frame_timestamp;
521 
522  /* Keyframe? */
523  pkt->flags = (pkt->data[0] & 0x80) ? 0 : AV_PKT_FLAG_KEY;
524 
525  /* Advance offset */
526  video->data_size -= frame_size + 4;
527  video->data_offset += frame_size + 4;
528 
529  return 0;
530 }
531 
533  AVPacket *pkt)
534 {
535  XMVDemuxContext *xmv = s->priv_data;
536  int result;
537 
538  if (xmv->video.current_frame == xmv->video.frame_count) {
539  /* No frames left in this packet, so we fetch a new one */
540 
541  result = xmv_fetch_new_packet(s);
542  if (result)
543  return result;
544  }
545 
546  if (xmv->current_stream == 0) {
547  /* Fetch a video frame */
548 
549  result = xmv_fetch_video_packet(s, pkt);
550  if (result)
551  return result;
552 
553  } else {
554  /* Fetch an audio frame */
555 
556  result = xmv_fetch_audio_packet(s, pkt, xmv->current_stream - 1);
557  if (result)
558  return result;
559  }
560 
561  /* Increase our counters */
562  if (++xmv->current_stream >= xmv->stream_count) {
563  xmv->current_stream = 0;
564  xmv->video.current_frame += 1;
565  }
566 
567  return 0;
568 }
569 
571  .name = "xmv",
572  .long_name = NULL_IF_CONFIG_SMALL("Microsoft XMV"),
573  .priv_data_size = sizeof(XMVDemuxContext),
578 };