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nsvdec.c
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1 /*
2  * NSV demuxer
3  * Copyright (c) 2004 The FFmpeg Project
4  *
5  * first version by Francois Revol <revol@free.fr>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include "libavutil/attributes.h"
25 #include "libavutil/mathematics.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "libavutil/dict.h"
29 #include "libavutil/intreadwrite.h"
30 
31 /* max bytes to crawl for trying to resync
32  * stupid streaming servers don't start at chunk boundaries...
33  */
34 #define NSV_MAX_RESYNC (500*1024)
35 #define NSV_MAX_RESYNC_TRIES 300
36 
37 /*
38  * References:
39  * (1) http://www.multimedia.cx/nsv-format.txt
40  * seems someone came to the same conclusions as me, and updated it:
41  * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
42  * http://www.stud.ktu.lt/~vitslav/nsv/
43  * official docs
44  * (3) http://ultravox.aol.com/NSVFormat.rtf
45  * Sample files:
46  * (S1) http://www.nullsoft.com/nsv/samples/
47  * http://www.nullsoft.com/nsv/samples/faster.nsv
48  * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
49  */
50 
51 /*
52  * notes on the header (Francois Revol):
53  *
54  * It is followed by strings, then a table, but nothing tells
55  * where the table begins according to (1). After checking faster.nsv,
56  * I believe NVSf[16-19] gives the size of the strings data
57  * (that is the offset of the data table after the header).
58  * After checking all samples from (S1) all confirms this.
59  *
60  * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
61  * I noticed there was about 1 NVSs chunk/s, so I ran
62  * strings faster.nsv | grep NSVs | wc -l
63  * which gave me 180. That leads me to think that NSVf[12-15] might be the
64  * file length in milliseconds.
65  * Let's try that:
66  * 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
67  * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
68  *
69  * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
70  * so the header seems to not be mandatory. (for streaming).
71  *
72  * index slice duration check (excepts nsvtrailer.nsv):
73  * 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
74  */
75 
76 /*
77  * TODO:
78  * - handle timestamps !!!
79  * - use index
80  * - mime-type in probe()
81  * - seek
82  */
83 
84 #if 0
85 struct NSVf_header {
86  uint32_t chunk_tag; /* 'NSVf' */
87  uint32_t chunk_size;
88  uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
89  uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
90  uint32_t info_strings_size; /* size of the info strings */ //unknown2;
91  uint32_t table_entries;
92  uint32_t table_entries_used; /* the left ones should be -1 */
93 };
94 
95 struct NSVs_header {
96  uint32_t chunk_tag; /* 'NSVs' */
97  uint32_t v4cc; /* or 'NONE' */
98  uint32_t a4cc; /* or 'NONE' */
99  uint16_t vwidth; /* av_assert0(vwidth%16==0) */
100  uint16_t vheight; /* av_assert0(vheight%16==0) */
101  uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
102  uint16_t unknown;
103 };
104 
105 struct nsv_avchunk_header {
106  uint8_t vchunk_size_lsb;
107  uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
108  uint16_t achunk_size;
109 };
110 
111 struct nsv_pcm_header {
112  uint8_t bits_per_sample;
113  uint8_t channel_count;
114  uint16_t sample_rate;
115 };
116 #endif
117 
118 /* variation from avi.h */
119 /*typedef struct CodecTag {
120  int id;
121  unsigned int tag;
122 } CodecTag;*/
123 
124 /* tags */
125 
126 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
127 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
128 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
129 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
130 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
131 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
132 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
133 
134 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
135 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
136 
137 /* hardcoded stream indexes */
138 #define NSV_ST_VIDEO 0
139 #define NSV_ST_AUDIO 1
140 #define NSV_ST_SUBT 2
141 
142 enum NSVStatus {
151 };
152 
153 typedef struct NSVStream {
154  int frame_offset; /* current frame (video) or byte (audio) counter
155  (used to compute the pts) */
156  int scale;
157  int rate;
158  int sample_size; /* audio only data */
159  int start;
160 
161  int new_frame_offset; /* temporary storage (used during seek) */
162  int cum_len; /* temporary storage (used during seek) */
163 } NSVStream;
164 
165 typedef struct {
167  int NSVf_end;
168  uint32_t *nsvs_file_offset;
171  AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
172  /* cached */
173  int64_t duration;
174  uint32_t vtag, atag;
175  uint16_t vwidth, vheight;
176  int16_t avsync;
178  uint32_t *nsvs_timestamps;
179  //DVDemuxContext* dv_demux;
180 } NSVContext;
181 
183  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
184  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
185  { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
186  { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
187  { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
188  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
189  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
190  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
191  { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
192  { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') },
193 /*
194  { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
195  { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
196 */
197  { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
198  { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
199  { AV_CODEC_ID_NONE, 0 },
200 };
201 
203  { AV_CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
204  { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
205  { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
206  { AV_CODEC_ID_AAC, MKTAG('V', 'L', 'B', ' ') },
207  { AV_CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
208  { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
209  { AV_CODEC_ID_NONE, 0 },
210 };
211 
212 //static int nsv_load_index(AVFormatContext *s);
213 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
214 
215 #define print_tag(str, tag, size) \
216  av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
217  str, tag & 0xff, \
218  (tag >> 8) & 0xff, \
219  (tag >> 16) & 0xff, \
220  (tag >> 24) & 0xff);
221 
222 /* try to find something we recognize, and set the state accordingly */
224 {
225  NSVContext *nsv = s->priv_data;
226  AVIOContext *pb = s->pb;
227  uint32_t v = 0;
228  int i;
229 
230  av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
231 
232  //nsv->state = NSV_UNSYNC;
233 
234  for (i = 0; i < NSV_MAX_RESYNC; i++) {
235  if (avio_feof(pb)) {
236  av_dlog(s, "NSV EOF\n");
237  nsv->state = NSV_UNSYNC;
238  return -1;
239  }
240  v <<= 8;
241  v |= avio_r8(pb);
242  if (i < 8) {
243  av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
244  }
245 
246  if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
247  av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
248  nsv->state = NSV_FOUND_BEEF;
249  return 0;
250  }
251  /* we read as big-endian, thus the MK*BE* */
252  if (v == TB_NSVF) { /* NSVf */
253  av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
254  nsv->state = NSV_FOUND_NSVF;
255  return 0;
256  }
257  if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
258  av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
259  nsv->state = NSV_FOUND_NSVS;
260  return 0;
261  }
262 
263  }
264  av_dlog(s, "NSV sync lost\n");
265  return -1;
266 }
267 
269 {
270  NSVContext *nsv = s->priv_data;
271  AVIOContext *pb = s->pb;
272  unsigned int av_unused file_size;
273  unsigned int size;
274  int64_t duration;
275  int strings_size;
276  int table_entries;
277  int table_entries_used;
278 
279  av_dlog(s, "%s()\n", __FUNCTION__);
280 
281  nsv->state = NSV_UNSYNC; /* in case we fail */
282 
283  size = avio_rl32(pb);
284  if (size < 28)
285  return -1;
286  nsv->NSVf_end = size;
287 
288  //s->file_size = (uint32_t)avio_rl32(pb);
289  file_size = (uint32_t)avio_rl32(pb);
290  av_dlog(s, "NSV NSVf chunk_size %u\n", size);
291  av_dlog(s, "NSV NSVf file_size %u\n", file_size);
292 
293  nsv->duration = duration = avio_rl32(pb); /* in ms */
294  av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
295  // XXX: store it in AVStreams
296 
297  strings_size = avio_rl32(pb);
298  table_entries = avio_rl32(pb);
299  table_entries_used = avio_rl32(pb);
300  av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
301  strings_size, table_entries, table_entries_used);
302  if (avio_feof(pb))
303  return -1;
304 
305  av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
306 
307  if (strings_size > 0) {
308  char *strings; /* last byte will be '\0' to play safe with str*() */
309  char *p, *endp;
310  char *token, *value;
311  char quote;
312 
313  p = strings = av_mallocz((size_t)strings_size + 1);
314  if (!p)
315  return AVERROR(ENOMEM);
316  endp = strings + strings_size;
317  avio_read(pb, strings, strings_size);
318  while (p < endp) {
319  while (*p == ' ')
320  p++; /* strip out spaces */
321  if (p >= endp-2)
322  break;
323  token = p;
324  p = strchr(p, '=');
325  if (!p || p >= endp-2)
326  break;
327  *p++ = '\0';
328  quote = *p++;
329  value = p;
330  p = strchr(p, quote);
331  if (!p || p >= endp)
332  break;
333  *p++ = '\0';
334  av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
335  av_dict_set(&s->metadata, token, value, 0);
336  }
337  av_free(strings);
338  }
339  if (avio_feof(pb))
340  return -1;
341 
342  av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
343 
344  if (table_entries_used > 0) {
345  int i;
346  nsv->index_entries = table_entries_used;
347  if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
348  return -1;
349  nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
350  if (!nsv->nsvs_file_offset)
351  return AVERROR(ENOMEM);
352 
353  for(i=0;i<table_entries_used;i++)
354  nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
355 
356  if(table_entries > table_entries_used &&
357  avio_rl32(pb) == MKTAG('T','O','C','2')) {
358  nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
359  if (!nsv->nsvs_timestamps)
360  return AVERROR(ENOMEM);
361  for(i=0;i<table_entries_used;i++) {
362  nsv->nsvs_timestamps[i] = avio_rl32(pb);
363  }
364  }
365  }
366 
367  av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
368 
369  avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
370 
371  if (avio_feof(pb))
372  return -1;
373  nsv->state = NSV_HAS_READ_NSVF;
374  return 0;
375 }
376 
378 {
379  NSVContext *nsv = s->priv_data;
380  AVIOContext *pb = s->pb;
381  uint32_t vtag, atag;
382  uint16_t vwidth, vheight;
383  AVRational framerate;
384  int i;
385  AVStream *st;
386  NSVStream *nst;
387  av_dlog(s, "%s()\n", __FUNCTION__);
388 
389  vtag = avio_rl32(pb);
390  atag = avio_rl32(pb);
391  vwidth = avio_rl16(pb);
392  vheight = avio_rl16(pb);
393  i = avio_r8(pb);
394 
395  av_dlog(s, "NSV NSVs framerate code %2x\n", i);
396  if(i&0x80) { /* odd way of giving native framerates from docs */
397  int t=(i & 0x7F)>>2;
398  if(t<16) framerate = (AVRational){1, t+1};
399  else framerate = (AVRational){t-15, 1};
400 
401  if(i&1){
402  framerate.num *= 1000;
403  framerate.den *= 1001;
404  }
405 
406  if((i&3)==3) framerate.num *= 24;
407  else if((i&3)==2) framerate.num *= 25;
408  else framerate.num *= 30;
409  }
410  else
411  framerate= (AVRational){i, 1};
412 
413  nsv->avsync = avio_rl16(pb);
414  nsv->framerate = framerate;
415 
416  print_tag("NSV NSVs vtag", vtag, 0);
417  print_tag("NSV NSVs atag", atag, 0);
418  av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
419 
420  /* XXX change to ap != NULL ? */
421  if (s->nb_streams == 0) { /* streams not yet published, let's do that */
422  nsv->vtag = vtag;
423  nsv->atag = atag;
424  nsv->vwidth = vwidth;
425  nsv->vheight = vwidth;
426  if (vtag != T_NONE) {
427  int i;
428  st = avformat_new_stream(s, NULL);
429  if (!st)
430  goto fail;
431 
432  st->id = NSV_ST_VIDEO;
433  nst = av_mallocz(sizeof(NSVStream));
434  if (!nst)
435  goto fail;
436  st->priv_data = nst;
438  st->codec->codec_tag = vtag;
439  st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
440  st->codec->width = vwidth;
441  st->codec->height = vheight;
442  st->codec->bits_per_coded_sample = 24; /* depth XXX */
443 
444  avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
445  st->start_time = 0;
446  st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
447 
448  for(i=0;i<nsv->index_entries;i++) {
449  if(nsv->nsvs_timestamps) {
451  0, 0, AVINDEX_KEYFRAME);
452  } else {
453  int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
454  av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
455  }
456  }
457  }
458  if (atag != T_NONE) {
459  st = avformat_new_stream(s, NULL);
460  if (!st)
461  goto fail;
462 
463  st->id = NSV_ST_AUDIO;
464  nst = av_mallocz(sizeof(NSVStream));
465  if (!nst)
466  goto fail;
467  st->priv_data = nst;
469  st->codec->codec_tag = atag;
470  st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
471 
472  st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
473 
474  /* set timebase to common denominator of ms and framerate */
475  avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
476  st->start_time = 0;
477  st->duration = (int64_t)nsv->duration * framerate.num;
478  }
479  } else {
480  if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
481  av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
482  //return -1;
483  }
484  }
485 
486  nsv->state = NSV_HAS_READ_NSVS;
487  return 0;
488 fail:
489  /* XXX */
490  nsv->state = NSV_UNSYNC;
491  return -1;
492 }
493 
495 {
496  NSVContext *nsv = s->priv_data;
497  int i, err;
498 
499  av_dlog(s, "%s()\n", __FUNCTION__);
500  av_dlog(s, "filename '%s'\n", s->filename);
501 
502  nsv->state = NSV_UNSYNC;
503  nsv->ahead[0].data = nsv->ahead[1].data = NULL;
504 
505  for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
506  if (nsv_resync(s) < 0)
507  return -1;
508  if (nsv->state == NSV_FOUND_NSVF) {
509  err = nsv_parse_NSVf_header(s);
510  if (err < 0)
511  return err;
512  }
513  /* we need the first NSVs also... */
514  if (nsv->state == NSV_FOUND_NSVS) {
515  err = nsv_parse_NSVs_header(s);
516  if (err < 0)
517  return err;
518  break; /* we just want the first one */
519  }
520  }
521  if (s->nb_streams < 1) /* no luck so far */
522  return -1;
523  /* now read the first chunk, so we can attempt to decode more info */
524  err = nsv_read_chunk(s, 1);
525 
526  av_dlog(s, "parsed header\n");
527  return err;
528 }
529 
530 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
531 {
532  NSVContext *nsv = s->priv_data;
533  AVIOContext *pb = s->pb;
534  AVStream *st[2] = {NULL, NULL};
535  NSVStream *nst;
536  AVPacket *pkt;
537  int i, err = 0;
538  uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
539  uint32_t vsize;
540  uint16_t asize;
541  uint16_t auxsize;
542  int ret;
543 
544  av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
545 
546  if (nsv->ahead[0].data || nsv->ahead[1].data)
547  return 0; //-1; /* hey! eat what you've in your plate first! */
548 
549 null_chunk_retry:
550  if (avio_feof(pb))
551  return -1;
552 
553  for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
554  err = nsv_resync(s);
555  if (err < 0)
556  return err;
557  if (nsv->state == NSV_FOUND_NSVS)
558  err = nsv_parse_NSVs_header(s);
559  if (err < 0)
560  return err;
561  if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
562  return -1;
563 
564  auxcount = avio_r8(pb);
565  vsize = avio_rl16(pb);
566  asize = avio_rl16(pb);
567  vsize = (vsize << 4) | (auxcount >> 4);
568  auxcount &= 0x0f;
569  av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
570  /* skip aux stuff */
571  for (i = 0; i < auxcount; i++) {
572  uint32_t av_unused auxtag;
573  auxsize = avio_rl16(pb);
574  auxtag = avio_rl32(pb);
575  av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
576  (auxtag & 0x0ff),
577  ((auxtag >> 8) & 0x0ff),
578  ((auxtag >> 16) & 0x0ff),
579  ((auxtag >> 24) & 0x0ff),
580  auxsize);
581  avio_skip(pb, auxsize);
582  vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
583  }
584 
585  if (avio_feof(pb))
586  return -1;
587  if (!vsize && !asize) {
588  nsv->state = NSV_UNSYNC;
589  goto null_chunk_retry;
590  }
591 
592  /* map back streams to v,a */
593  if (s->nb_streams > 0)
594  st[s->streams[0]->id] = s->streams[0];
595  if (s->nb_streams > 1)
596  st[s->streams[1]->id] = s->streams[1];
597 
598  if (vsize && st[NSV_ST_VIDEO]) {
599  nst = st[NSV_ST_VIDEO]->priv_data;
600  pkt = &nsv->ahead[NSV_ST_VIDEO];
601  if ((ret = av_get_packet(pb, pkt, vsize)) < 0)
602  return ret;
603  pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
604  pkt->dts = nst->frame_offset;
605  pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
606  for (i = 0; i < FFMIN(8, vsize); i++)
607  av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
608  }
609  if(st[NSV_ST_VIDEO])
610  ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
611 
612  if (asize && st[NSV_ST_AUDIO]) {
613  nst = st[NSV_ST_AUDIO]->priv_data;
614  pkt = &nsv->ahead[NSV_ST_AUDIO];
615  /* read raw audio specific header on the first audio chunk... */
616  /* on ALL audio chunks ?? seems so! */
617  if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
618  uint8_t bps;
619  uint8_t channels;
620  uint16_t samplerate;
621  bps = avio_r8(pb);
622  channels = avio_r8(pb);
623  samplerate = avio_rl16(pb);
624  asize-=4;
625  av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
626  if (fill_header) {
627  st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
628  if (bps != 16) {
629  av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
630  }
631  if(channels)
632  bps /= channels; // ???
633  else
634  av_log(s, AV_LOG_WARNING, "Channels is 0\n");
635  if (bps == 8)
637  samplerate /= 4;/* UGH ??? XXX */
638  channels = 1;
639  st[NSV_ST_AUDIO]->codec->channels = channels;
640  st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
641  av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
642  }
643  }
644  if ((ret = av_get_packet(pb, pkt, asize)) < 0)
645  return ret;
646  pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
647  pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
648  if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
649  /* on a nsvs frame we have new information on a/v sync */
650  pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
651  pkt->dts *= (int64_t)1000 * nsv->framerate.den;
652  pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
653  av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
654  }
655  nst->frame_offset++;
656  }
657 
658  nsv->state = NSV_UNSYNC;
659  return 0;
660 }
661 
662 
664 {
665  NSVContext *nsv = s->priv_data;
666  int i, err = 0;
667 
668  av_dlog(s, "%s()\n", __FUNCTION__);
669 
670  /* in case we don't already have something to eat ... */
671  if (!nsv->ahead[0].data && !nsv->ahead[1].data)
672  err = nsv_read_chunk(s, 0);
673  if (err < 0)
674  return err;
675 
676  /* now pick one of the plates */
677  for (i = 0; i < 2; i++) {
678  if (nsv->ahead[i].data) {
679  av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
680  /* avoid the cost of new_packet + memcpy(->data) */
681  memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
682  nsv->ahead[i].data = NULL; /* we ate that one */
683  return pkt->size;
684  }
685  }
686 
687  /* this restaurant is not approvisionned :^] */
688  return -1;
689 }
690 
691 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
692 {
693  NSVContext *nsv = s->priv_data;
694  AVStream *st = s->streams[stream_index];
695  NSVStream *nst = st->priv_data;
696  int index;
697 
698  index = av_index_search_timestamp(st, timestamp, flags);
699  if(index < 0)
700  return -1;
701 
702  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
703  return -1;
704 
706  nsv->state = NSV_UNSYNC;
707  return 0;
708 }
709 
711 {
712  NSVContext *nsv = s->priv_data;
713 
714  av_freep(&nsv->nsvs_file_offset);
715  av_freep(&nsv->nsvs_timestamps);
716  if (nsv->ahead[0].data)
717  av_free_packet(&nsv->ahead[0]);
718  if (nsv->ahead[1].data)
719  av_free_packet(&nsv->ahead[1]);
720  return 0;
721 }
722 
723 static int nsv_probe(AVProbeData *p)
724 {
725  int i, score = 0;
726 
727  av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
728  /* check file header */
729  /* streamed files might not have any header */
730  if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
731  p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
732  return AVPROBE_SCORE_MAX;
733  /* XXX: do streamed files always start at chunk boundary ?? */
734  /* or do we need to search NSVs in the byte stream ? */
735  /* seems the servers don't bother starting clean chunks... */
736  /* sometimes even the first header is at 9KB or something :^) */
737  for (i = 1; i < p->buf_size - 3; i++) {
738  if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {
739  /* Get the chunk size and check if at the end we are getting 0xBEEF */
740  int vsize = AV_RL24(p->buf+i+19) >> 4;
741  int asize = AV_RL16(p->buf+i+22);
742  int offset = i + 23 + asize + vsize + 1;
743  if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)
744  return 4*AVPROBE_SCORE_MAX/5;
745  score = AVPROBE_SCORE_MAX/5;
746  }
747  }
748  /* so we'll have more luck on extension... */
749  if (av_match_ext(p->filename, "nsv"))
751  /* FIXME: add mime-type check */
752  return score;
753 }
754 
756  .name = "nsv",
757  .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
758  .priv_data_size = sizeof(NSVContext),
764 };