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nsvdec.c
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1 /*
2  * NSV demuxer
3  * Copyright (c) 2004 The FFmpeg Project
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/attributes.h"
23 #include "libavutil/mathematics.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/intreadwrite.h"
28 
29 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
30 #define CHECK_SUBSEQUENT_NSVS
31 //#define DISABLE_AUDIO
32 
33 /* max bytes to crawl for trying to resync
34  * stupid streaming servers don't start at chunk boundaries...
35  */
36 #define NSV_MAX_RESYNC (500*1024)
37 #define NSV_MAX_RESYNC_TRIES 300
38 
39 /*
40  * First version by Francois Revol - revol@free.fr
41  * References:
42  * (1) http://www.multimedia.cx/nsv-format.txt
43  * seems someone came to the same conclusions as me, and updated it:
44  * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
45  * http://www.stud.ktu.lt/~vitslav/nsv/
46  * official docs
47  * (3) http://ultravox.aol.com/NSVFormat.rtf
48  * Sample files:
49  * (S1) http://www.nullsoft.com/nsv/samples/
50  * http://www.nullsoft.com/nsv/samples/faster.nsv
51  * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
52  */
53 
54 /*
55  * notes on the header (Francois Revol):
56  *
57  * It is followed by strings, then a table, but nothing tells
58  * where the table begins according to (1). After checking faster.nsv,
59  * I believe NVSf[16-19] gives the size of the strings data
60  * (that is the offset of the data table after the header).
61  * After checking all samples from (S1) all confirms this.
62  *
63  * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
64  * I noticed there was about 1 NVSs chunk/s, so I ran
65  * strings faster.nsv | grep NSVs | wc -l
66  * which gave me 180. That leads me to think that NSVf[12-15] might be the
67  * file length in milliseconds.
68  * Let's try that:
69  * for f in *.nsv; do HTIME="$(od -t x4 "$f" | head -1 | sed 's/.* //')"; echo "'$f' $((0x$HTIME))s = $((0x$HTIME/1000/60)):$((0x$HTIME/1000%60))"; done
70  * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
71  *
72  * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
73  * so the header seems to not be mandatory. (for streaming).
74  *
75  * index slice duration check (excepts nsvtrailer.nsv):
76  * for f in [^n]*.nsv; do DUR="$(ffmpeg -i "$f" 2>/dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"; IC="$(ffmpeg -i "$f" 2>/dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"; echo "duration $DUR, slite time $(($DUR/$IC))"; done
77  */
78 
79 /*
80  * TODO:
81  * - handle timestamps !!!
82  * - use index
83  * - mime-type in probe()
84  * - seek
85  */
86 
87 #if 0
88 struct NSVf_header {
89  uint32_t chunk_tag; /* 'NSVf' */
90  uint32_t chunk_size;
91  uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
92  uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
93  uint32_t info_strings_size; /* size of the info strings */ //unknown2;
94  uint32_t table_entries;
95  uint32_t table_entries_used; /* the left ones should be -1 */
96 };
97 
98 struct NSVs_header {
99  uint32_t chunk_tag; /* 'NSVs' */
100  uint32_t v4cc; /* or 'NONE' */
101  uint32_t a4cc; /* or 'NONE' */
102  uint16_t vwidth; /* av_assert(vwidth%16==0) */
103  uint16_t vheight; /* av_assert(vheight%16==0) */
104  uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
105  uint16_t unknown;
106 };
107 
108 struct nsv_avchunk_header {
109  uint8_t vchunk_size_lsb;
110  uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
111  uint16_t achunk_size;
112 };
113 
114 struct nsv_pcm_header {
115  uint8_t bits_per_sample;
116  uint8_t channel_count;
117  uint16_t sample_rate;
118 };
119 #endif
120 
121 /* variation from avi.h */
122 /*typedef struct CodecTag {
123  int id;
124  unsigned int tag;
125 } CodecTag;*/
126 
127 /* tags */
128 
129 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
130 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
131 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
132 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
133 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
134 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
135 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
136 
137 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
138 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
139 
140 /* hardcoded stream indexes */
141 #define NSV_ST_VIDEO 0
142 #define NSV_ST_AUDIO 1
143 #define NSV_ST_SUBT 2
144 
145 enum NSVStatus {
154 };
155 
156 typedef struct NSVStream {
157  int frame_offset; /* current frame (video) or byte (audio) counter
158  (used to compute the pts) */
159  int scale;
160  int rate;
161  int sample_size; /* audio only data */
162  int start;
163 
164  int new_frame_offset; /* temporary storage (used during seek) */
165  int cum_len; /* temporary storage (used during seek) */
166 } NSVStream;
167 
168 typedef struct {
170  int NSVf_end;
171  uint32_t *nsvs_file_offset;
174  AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
175  /* cached */
176  int64_t duration;
177  uint32_t vtag, atag;
178  uint16_t vwidth, vheight;
179  int16_t avsync;
181  uint32_t *nsvs_timestamps;
182  //DVDemuxContext* dv_demux;
183 } NSVContext;
184 
186  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
187  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
188  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
189  { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
190  { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
191  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
192  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
193  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
194  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
195  { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') },
196 /*
197  { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
198  { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
199 */
200  { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
201  { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
202  { AV_CODEC_ID_NONE, 0 },
203 };
204 
206  { AV_CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
207  { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
208  { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
209  { AV_CODEC_ID_AAC, MKTAG('V', 'L', 'B', ' ') },
210  { AV_CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
211  { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
212  { AV_CODEC_ID_NONE, 0 },
213 };
214 
215 //static int nsv_load_index(AVFormatContext *s);
216 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
217 
218 #define print_tag(str, tag, size) \
219  av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
220  str, tag & 0xff, \
221  (tag >> 8) & 0xff, \
222  (tag >> 16) & 0xff, \
223  (tag >> 24) & 0xff);
224 
225 /* try to find something we recognize, and set the state accordingly */
227 {
228  NSVContext *nsv = s->priv_data;
229  AVIOContext *pb = s->pb;
230  uint32_t v = 0;
231  int i;
232 
233  av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
234 
235  //nsv->state = NSV_UNSYNC;
236 
237  for (i = 0; i < NSV_MAX_RESYNC; i++) {
238  if (url_feof(pb)) {
239  av_dlog(s, "NSV EOF\n");
240  nsv->state = NSV_UNSYNC;
241  return -1;
242  }
243  v <<= 8;
244  v |= avio_r8(pb);
245  if (i < 8) {
246  av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
247  }
248 
249  if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
250  av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
251  nsv->state = NSV_FOUND_BEEF;
252  return 0;
253  }
254  /* we read as big-endian, thus the MK*BE* */
255  if (v == TB_NSVF) { /* NSVf */
256  av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
257  nsv->state = NSV_FOUND_NSVF;
258  return 0;
259  }
260  if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
261  av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
262  nsv->state = NSV_FOUND_NSVS;
263  return 0;
264  }
265 
266  }
267  av_dlog(s, "NSV sync lost\n");
268  return -1;
269 }
270 
272 {
273  NSVContext *nsv = s->priv_data;
274  AVIOContext *pb = s->pb;
275  unsigned int av_unused file_size;
276  unsigned int size;
277  int64_t duration;
278  int strings_size;
279  int table_entries;
280  int table_entries_used;
281 
282  av_dlog(s, "%s()\n", __FUNCTION__);
283 
284  nsv->state = NSV_UNSYNC; /* in case we fail */
285 
286  size = avio_rl32(pb);
287  if (size < 28)
288  return -1;
289  nsv->NSVf_end = size;
290 
291  //s->file_size = (uint32_t)avio_rl32(pb);
292  file_size = (uint32_t)avio_rl32(pb);
293  av_dlog(s, "NSV NSVf chunk_size %u\n", size);
294  av_dlog(s, "NSV NSVf file_size %u\n", file_size);
295 
296  nsv->duration = duration = avio_rl32(pb); /* in ms */
297  av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
298  // XXX: store it in AVStreams
299 
300  strings_size = avio_rl32(pb);
301  table_entries = avio_rl32(pb);
302  table_entries_used = avio_rl32(pb);
303  av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
304  strings_size, table_entries, table_entries_used);
305  if (url_feof(pb))
306  return -1;
307 
308  av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
309 
310  if (strings_size > 0) {
311  char *strings; /* last byte will be '\0' to play safe with str*() */
312  char *p, *endp;
313  char *token, *value;
314  char quote;
315 
316  p = strings = av_mallocz((size_t)strings_size + 1);
317  if (!p)
318  return AVERROR(ENOMEM);
319  endp = strings + strings_size;
320  avio_read(pb, strings, strings_size);
321  while (p < endp) {
322  while (*p == ' ')
323  p++; /* strip out spaces */
324  if (p >= endp-2)
325  break;
326  token = p;
327  p = strchr(p, '=');
328  if (!p || p >= endp-2)
329  break;
330  *p++ = '\0';
331  quote = *p++;
332  value = p;
333  p = strchr(p, quote);
334  if (!p || p >= endp)
335  break;
336  *p++ = '\0';
337  av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
338  av_dict_set(&s->metadata, token, value, 0);
339  }
340  av_free(strings);
341  }
342  if (url_feof(pb))
343  return -1;
344 
345  av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
346 
347  if (table_entries_used > 0) {
348  int i;
349  nsv->index_entries = table_entries_used;
350  if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
351  return -1;
352  nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
353  if (!nsv->nsvs_file_offset)
354  return AVERROR(ENOMEM);
355 
356  for(i=0;i<table_entries_used;i++)
357  nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
358 
359  if(table_entries > table_entries_used &&
360  avio_rl32(pb) == MKTAG('T','O','C','2')) {
361  nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
362  if (!nsv->nsvs_timestamps)
363  return AVERROR(ENOMEM);
364  for(i=0;i<table_entries_used;i++) {
365  nsv->nsvs_timestamps[i] = avio_rl32(pb);
366  }
367  }
368  }
369 
370  av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
371 
372 #ifdef DEBUG_DUMP_INDEX
373 #define V(v) ((v<0x20 || v > 127)?'.':v)
374  /* dump index */
375  av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
376  av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
377  for (i = 0; i < table_entries; i++) {
378  unsigned char b[8];
379  avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
380  avio_read(pb, b, 8);
381  av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
382  "%c%c%c%c%c%c%c%c\n",
383  nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
384  b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
385  V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
386  }
387  //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
388 #undef V
389 #endif
390 
391  avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
392 
393  if (url_feof(pb))
394  return -1;
395  nsv->state = NSV_HAS_READ_NSVF;
396  return 0;
397 }
398 
400 {
401  NSVContext *nsv = s->priv_data;
402  AVIOContext *pb = s->pb;
403  uint32_t vtag, atag;
404  uint16_t vwidth, vheight;
405  AVRational framerate;
406  int i;
407  AVStream *st;
408  NSVStream *nst;
409  av_dlog(s, "%s()\n", __FUNCTION__);
410 
411  vtag = avio_rl32(pb);
412  atag = avio_rl32(pb);
413  vwidth = avio_rl16(pb);
414  vheight = avio_rl16(pb);
415  i = avio_r8(pb);
416 
417  av_dlog(s, "NSV NSVs framerate code %2x\n", i);
418  if(i&0x80) { /* odd way of giving native framerates from docs */
419  int t=(i & 0x7F)>>2;
420  if(t<16) framerate = (AVRational){1, t+1};
421  else framerate = (AVRational){t-15, 1};
422 
423  if(i&1){
424  framerate.num *= 1000;
425  framerate.den *= 1001;
426  }
427 
428  if((i&3)==3) framerate.num *= 24;
429  else if((i&3)==2) framerate.num *= 25;
430  else framerate.num *= 30;
431  }
432  else
433  framerate= (AVRational){i, 1};
434 
435  nsv->avsync = avio_rl16(pb);
436  nsv->framerate = framerate;
437 
438  print_tag("NSV NSVs vtag", vtag, 0);
439  print_tag("NSV NSVs atag", atag, 0);
440  av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
441 
442  /* XXX change to ap != NULL ? */
443  if (s->nb_streams == 0) { /* streams not yet published, let's do that */
444  nsv->vtag = vtag;
445  nsv->atag = atag;
446  nsv->vwidth = vwidth;
447  nsv->vheight = vwidth;
448  if (vtag != T_NONE) {
449  int i;
450  st = avformat_new_stream(s, NULL);
451  if (!st)
452  goto fail;
453 
454  st->id = NSV_ST_VIDEO;
455  nst = av_mallocz(sizeof(NSVStream));
456  if (!nst)
457  goto fail;
458  st->priv_data = nst;
460  st->codec->codec_tag = vtag;
461  st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
462  st->codec->width = vwidth;
463  st->codec->height = vheight;
464  st->codec->bits_per_coded_sample = 24; /* depth XXX */
465 
466  avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
467  st->start_time = 0;
468  st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
469 
470  for(i=0;i<nsv->index_entries;i++) {
471  if(nsv->nsvs_timestamps) {
473  0, 0, AVINDEX_KEYFRAME);
474  } else {
475  int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
476  av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
477  }
478  }
479  }
480  if (atag != T_NONE) {
481 #ifndef DISABLE_AUDIO
482  st = avformat_new_stream(s, NULL);
483  if (!st)
484  goto fail;
485 
486  st->id = NSV_ST_AUDIO;
487  nst = av_mallocz(sizeof(NSVStream));
488  if (!nst)
489  goto fail;
490  st->priv_data = nst;
492  st->codec->codec_tag = atag;
493  st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
494 
495  st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
496 
497  /* set timebase to common denominator of ms and framerate */
498  avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
499  st->start_time = 0;
500  st->duration = (int64_t)nsv->duration * framerate.num;
501 #endif
502  }
503 #ifdef CHECK_SUBSEQUENT_NSVS
504  } else {
505  if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
506  av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
507  //return -1;
508  }
509 #endif /* CHECK_SUBSEQUENT_NSVS */
510  }
511 
512  nsv->state = NSV_HAS_READ_NSVS;
513  return 0;
514 fail:
515  /* XXX */
516  nsv->state = NSV_UNSYNC;
517  return -1;
518 }
519 
521 {
522  NSVContext *nsv = s->priv_data;
523  int i, err;
524 
525  av_dlog(s, "%s()\n", __FUNCTION__);
526  av_dlog(s, "filename '%s'\n", s->filename);
527 
528  nsv->state = NSV_UNSYNC;
529  nsv->ahead[0].data = nsv->ahead[1].data = NULL;
530 
531  for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
532  if (nsv_resync(s) < 0)
533  return -1;
534  if (nsv->state == NSV_FOUND_NSVF) {
535  err = nsv_parse_NSVf_header(s);
536  if (err < 0)
537  return err;
538  }
539  /* we need the first NSVs also... */
540  if (nsv->state == NSV_FOUND_NSVS) {
541  err = nsv_parse_NSVs_header(s);
542  if (err < 0)
543  return err;
544  break; /* we just want the first one */
545  }
546  }
547  if (s->nb_streams < 1) /* no luck so far */
548  return -1;
549  /* now read the first chunk, so we can attempt to decode more info */
550  err = nsv_read_chunk(s, 1);
551 
552  av_dlog(s, "parsed header\n");
553  return err;
554 }
555 
556 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
557 {
558  NSVContext *nsv = s->priv_data;
559  AVIOContext *pb = s->pb;
560  AVStream *st[2] = {NULL, NULL};
561  NSVStream *nst;
562  AVPacket *pkt;
563  int i, err = 0;
564  uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
565  uint32_t vsize;
566  uint16_t asize;
567  uint16_t auxsize;
568 
569  av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
570 
571  if (nsv->ahead[0].data || nsv->ahead[1].data)
572  return 0; //-1; /* hey! eat what you've in your plate first! */
573 
574 null_chunk_retry:
575  if (url_feof(pb))
576  return -1;
577 
578  for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
579  err = nsv_resync(s);
580  if (err < 0)
581  return err;
582  if (nsv->state == NSV_FOUND_NSVS)
583  err = nsv_parse_NSVs_header(s);
584  if (err < 0)
585  return err;
586  if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
587  return -1;
588 
589  auxcount = avio_r8(pb);
590  vsize = avio_rl16(pb);
591  asize = avio_rl16(pb);
592  vsize = (vsize << 4) | (auxcount >> 4);
593  auxcount &= 0x0f;
594  av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
595  /* skip aux stuff */
596  for (i = 0; i < auxcount; i++) {
597  uint32_t av_unused auxtag;
598  auxsize = avio_rl16(pb);
599  auxtag = avio_rl32(pb);
600  av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
601  (auxtag & 0x0ff),
602  ((auxtag >> 8) & 0x0ff),
603  ((auxtag >> 16) & 0x0ff),
604  ((auxtag >> 24) & 0x0ff),
605  auxsize);
606  avio_skip(pb, auxsize);
607  vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
608  }
609 
610  if (url_feof(pb))
611  return -1;
612  if (!vsize && !asize) {
613  nsv->state = NSV_UNSYNC;
614  goto null_chunk_retry;
615  }
616 
617  /* map back streams to v,a */
618  if (s->nb_streams > 0)
619  st[s->streams[0]->id] = s->streams[0];
620  if (s->nb_streams > 1)
621  st[s->streams[1]->id] = s->streams[1];
622 
623  if (vsize && st[NSV_ST_VIDEO]) {
624  nst = st[NSV_ST_VIDEO]->priv_data;
625  pkt = &nsv->ahead[NSV_ST_VIDEO];
626  av_get_packet(pb, pkt, vsize);
627  pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
628  pkt->dts = nst->frame_offset;
629  pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
630  for (i = 0; i < FFMIN(8, vsize); i++)
631  av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
632  }
633  if(st[NSV_ST_VIDEO])
634  ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
635 
636  if (asize && st[NSV_ST_AUDIO]) {
637  nst = st[NSV_ST_AUDIO]->priv_data;
638  pkt = &nsv->ahead[NSV_ST_AUDIO];
639  /* read raw audio specific header on the first audio chunk... */
640  /* on ALL audio chunks ?? seems so! */
641  if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
642  uint8_t bps;
643  uint8_t channels;
644  uint16_t samplerate;
645  bps = avio_r8(pb);
646  channels = avio_r8(pb);
647  samplerate = avio_rl16(pb);
648  asize-=4;
649  av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
650  if (fill_header) {
651  st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
652  if (bps != 16) {
653  av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
654  }
655  if(channels)
656  bps /= channels; // ???
657  else
658  av_log(s, AV_LOG_WARNING, "Channels is 0\n");
659  if (bps == 8)
661  samplerate /= 4;/* UGH ??? XXX */
662  channels = 1;
663  st[NSV_ST_AUDIO]->codec->channels = channels;
664  st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
665  av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
666  }
667  }
668  av_get_packet(pb, pkt, asize);
669  pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
670  pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
671  if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
672  /* on a nsvs frame we have new information on a/v sync */
673  pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
674  pkt->dts *= (int64_t)1000 * nsv->framerate.den;
675  pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
676  av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
677  }
678  nst->frame_offset++;
679  }
680 
681  nsv->state = NSV_UNSYNC;
682  return 0;
683 }
684 
685 
687 {
688  NSVContext *nsv = s->priv_data;
689  int i, err = 0;
690 
691  av_dlog(s, "%s()\n", __FUNCTION__);
692 
693  /* in case we don't already have something to eat ... */
694  if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
695  err = nsv_read_chunk(s, 0);
696  if (err < 0)
697  return err;
698 
699  /* now pick one of the plates */
700  for (i = 0; i < 2; i++) {
701  if (nsv->ahead[i].data) {
702  av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
703  /* avoid the cost of new_packet + memcpy(->data) */
704  memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
705  nsv->ahead[i].data = NULL; /* we ate that one */
706  return pkt->size;
707  }
708  }
709 
710  /* this restaurant is not approvisionned :^] */
711  return -1;
712 }
713 
714 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
715 {
716  NSVContext *nsv = s->priv_data;
717  AVStream *st = s->streams[stream_index];
718  NSVStream *nst = st->priv_data;
719  int index;
720 
721  index = av_index_search_timestamp(st, timestamp, flags);
722  if(index < 0)
723  return -1;
724 
725  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
726  return -1;
727 
729  nsv->state = NSV_UNSYNC;
730  return 0;
731 }
732 
734 {
735 /* int i; */
736  NSVContext *nsv = s->priv_data;
737 
738  av_freep(&nsv->nsvs_file_offset);
739  av_freep(&nsv->nsvs_timestamps);
740  if (nsv->ahead[0].data)
741  av_free_packet(&nsv->ahead[0]);
742  if (nsv->ahead[1].data)
743  av_free_packet(&nsv->ahead[1]);
744 
745 #if 0
746 
747  for(i=0;i<s->nb_streams;i++) {
748  AVStream *st = s->streams[i];
749  NSVStream *ast = st->priv_data;
750  if(ast){
751  av_free(ast->index_entries);
752  av_free(ast);
753  }
754  av_free(st->codec->palctrl);
755  }
756 
757 #endif
758  return 0;
759 }
760 
761 static int nsv_probe(AVProbeData *p)
762 {
763  int i, score = 0;
764 
765  av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
766  /* check file header */
767  /* streamed files might not have any header */
768  if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
769  p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
770  return AVPROBE_SCORE_MAX;
771  /* XXX: do streamed files always start at chunk boundary ?? */
772  /* or do we need to search NSVs in the byte stream ? */
773  /* seems the servers don't bother starting clean chunks... */
774  /* sometimes even the first header is at 9KB or something :^) */
775  for (i = 1; i < p->buf_size - 3; i++) {
776  if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {
777  /* Get the chunk size and check if at the end we are getting 0xBEEF */
778  int vsize = AV_RL24(p->buf+i+19) >> 4;
779  int asize = AV_RL16(p->buf+i+22);
780  int offset = i + 23 + asize + vsize + 1;
781  if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)
782  return 4*AVPROBE_SCORE_MAX/5;
783  score = AVPROBE_SCORE_MAX/5;
784  }
785  }
786  /* so we'll have more luck on extension... */
787  if (av_match_ext(p->filename, "nsv"))
788  return AVPROBE_SCORE_MAX/2;
789  /* FIXME: add mime-type check */
790  return score;
791 }
792 
794  .name = "nsv",
795  .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
796  .priv_data_size = sizeof(NSVContext),
802 };