libavformat/nsvdec.c

   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 #include "avformat.h"
  22 #include "riff.h"
  23
  24 //#define DEBUG
  25 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
  26 //#define DEBUG_SEEK
  27 #define CHECK_SUBSEQUENT_NSVS
  28 //#define DISABLE_AUDIO
  29
  30 /* max bytes to crawl for trying to resync
  31  * stupid streaming servers don't start at chunk boundaries...
  32  */
  33 #define NSV_MAX_RESYNC (500*1024)
  34 #define NSV_MAX_RESYNC_TRIES 300
  35
  36 /*
  37  * First version by Francois Revol - revol@free.fr
  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 #ifdef DEBUG
  85 #define PRINT(_v) printf _v
  86 #else
  87 #define PRINT(_v)
  88 #endif
  89
  90 #if 0
  91 struct NSVf_header {
  92     uint32_t chunk_tag; /* 'NSVf' */
  93     uint32_t chunk_size;
  94     uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
  95     uint32_t file_length; //unknown1;  /* what about MSB of file_size ? */
  96     uint32_t info_strings_size; /* size of the info strings */ //unknown2;
  97     uint32_t table_entries;
  98     uint32_t table_entries_used; /* the left ones should be -1 */
  99 };
 100
 101 struct NSVs_header {
 102     uint32_t chunk_tag; /* 'NSVs' */
 103     uint32_t v4cc;      /* or 'NONE' */
 104     uint32_t a4cc;      /* or 'NONE' */
 105     uint16_t vwidth;    /* assert(vwidth%16==0) */
 106     uint16_t vheight;   /* assert(vheight%16==0) */
 107     uint8_t framerate;  /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
 108     uint16_t unknown;
 109 };
 110
 111 struct nsv_avchunk_header {
 112     uint8_t vchunk_size_lsb;
 113     uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
 114     uint16_t achunk_size;
 115 };
 116
 117 struct nsv_pcm_header {
 118     uint8_t bits_per_sample;
 119     uint8_t channel_count;
 120     uint16_t sample_rate;
 121 };
 122 #endif
 123
 124 /* variation from avi.h */
 125 /*typedef struct CodecTag {
 126     int id;
 127     unsigned int tag;
 128 } CodecTag;*/
 129
 130 /* tags */
 131
 132 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
 133 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
 134 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
 135 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
 136 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
 137 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
 138 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
 139
 140 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
 141 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
 142
 143 /* hardcoded stream indexes */
 144 #define NSV_ST_VIDEO 0
 145 #define NSV_ST_AUDIO 1
 146 #define NSV_ST_SUBT 2
 147
 148 enum NSVStatus {
 149     NSV_UNSYNC,
 150     NSV_FOUND_NSVF,
 151     NSV_HAS_READ_NSVF,
 152     NSV_FOUND_NSVS,
 153     NSV_HAS_READ_NSVS,
 154     NSV_FOUND_BEEF,
 155     NSV_GOT_VIDEO,
 156     NSV_GOT_AUDIO,
 157 };
 158
 159 typedef struct NSVStream {
 160     int frame_offset; /* current frame (video) or byte (audio) counter
 161                          (used to compute the pts) */
 162     int scale;
 163     int rate;
 164     int sample_size; /* audio only data */
 165     int start;
 166
 167     int new_frame_offset; /* temporary storage (used during seek) */
 168     int cum_len; /* temporary storage (used during seek) */
 169 } NSVStream;
 170
 171 typedef struct {
 172     int  base_offset;
 173     int  NSVf_end;
 174     uint32_t *nsvf_index_data;
 175     int index_entries;
 176     enum NSVStatus state;
 177     AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
 178     /* cached */
 179     int64_t duration;
 180     uint32_t vtag, atag;
 181     uint16_t vwidth, vheight;
 182     int16_t avsync;
 183     //DVDemuxContext* dv_demux;
 184 } NSVContext;
 185
 186 static const AVCodecTag nsv_codec_video_tags[] = {
 187     { CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
 188     { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
 189     { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
 190     { CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
 191     { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
 192     { CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
 193     { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
 194     { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
 195     { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
 196 /*
 197     { CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
 198     { CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
 199 */
 200     { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
 201     { CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
 202     { 0, 0 },
 203 };
 204
 205 static const AVCodecTag nsv_codec_audio_tags[] = {
 206     { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
 207     { CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
 208     { CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') }, /* _CUTTED__MUXED_2 Heads - Out Of The City.nsv */
 209     { CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
 210     { 0, 0 },
 211 };
 212
 213 //static int nsv_load_index(AVFormatContext *s);
 214 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
 215
 216 #ifdef DEBUG
 217 static void print_tag(const char *str, unsigned int tag, int size)
 218 {
 219     printf("%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 #endif
 226
 227 /* try to find something we recognize, and set the state accordingly */
 228 static int nsv_resync(AVFormatContext *s)
 229 {
 230     NSVContext *nsv = s->priv_data;
 231     ByteIOContext *pb = s->pb;
 232     uint32_t v = 0;
 233     int i;
 234
 235     PRINT(("%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, url_ftell(pb), nsv->state));
 236
 237     //nsv->state = NSV_UNSYNC;
 238
 239     for (i = 0; i < NSV_MAX_RESYNC; i++) {
 240         if (url_feof(pb)) {
 241             PRINT(("NSV EOF\n"));
 242             nsv->state = NSV_UNSYNC;
 243             return -1;
 244         }
 245         v <<= 8;
 246         v |= get_byte(pb);
 247 /*
 248         if (i < 8) {
 249             PRINT(("NSV resync: [%d] = %02x\n", i, v & 0x0FF));
 250         }
 251 */
 252
 253         if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
 254             PRINT(("NSV resynced on BEEF after %d bytes\n", i+1));
 255             nsv->state = NSV_FOUND_BEEF;
 256             return 0;
 257         }
 258         /* we read as big endian, thus the MK*BE* */
 259         if (v == TB_NSVF) { /* NSVf */
 260             PRINT(("NSV resynced on NSVf after %d bytes\n", i+1));
 261             nsv->state = NSV_FOUND_NSVF;
 262             return 0;
 263         }
 264         if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
 265             PRINT(("NSV resynced on NSVs after %d bytes\n", i+1));
 266             nsv->state = NSV_FOUND_NSVS;
 267             return 0;
 268         }
 269
 270     }
 271     PRINT(("NSV sync lost\n"));
 272     return -1;
 273 }
 274
 275 static int nsv_parse_NSVf_header(AVFormatContext *s, AVFormatParameters *ap)
 276 {
 277     NSVContext *nsv = s->priv_data;
 278     ByteIOContext *pb = s->pb;
 279     unsigned int file_size, size;
 280     int64_t duration;
 281     int strings_size;
 282     int table_entries;
 283     int table_entries_used;
 284
 285     PRINT(("%s()\n", __FUNCTION__));
 286
 287     nsv->state = NSV_UNSYNC; /* in case we fail */
 288
 289     size = get_le32(pb);
 290     if (size < 28)
 291         return -1;
 292     nsv->NSVf_end = size;
 293
 294     //s->file_size = (uint32_t)get_le32(pb);
 295     file_size = (uint32_t)get_le32(pb);
 296     PRINT(("NSV NSVf chunk_size %u\n", size));
 297     PRINT(("NSV NSVf file_size %u\n", file_size));
 298
 299     nsv->duration = duration = get_le32(pb); /* in ms */
 300     PRINT(("NSV NSVf duration %"PRId64" ms\n", duration));
 301     // XXX: store it in AVStreams
 302
 303     strings_size = get_le32(pb);
 304     table_entries = get_le32(pb);
 305     table_entries_used = get_le32(pb);
 306     PRINT(("NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
 307             strings_size, table_entries, table_entries_used));
 308     if (url_feof(pb))
 309         return -1;
 310
 311     PRINT(("NSV got header; filepos %"PRId64"\n", url_ftell(pb)));
 312
 313     if (strings_size > 0) {
 314         char *strings; /* last byte will be '\0' to play safe with str*() */
 315         char *p, *endp;
 316         char *token, *value;
 317         char quote;
 318
 319         p = strings = av_mallocz(strings_size + 1);
 320         endp = strings + strings_size;
 321         get_buffer(pb, strings, strings_size);
 322         while (p < endp) {
 323             while (*p == ' ')
 324                 p++; /* strip out spaces */
 325             if (p >= endp-2)
 326                 break;
 327             token = p;
 328             p = strchr(p, '=');
 329             if (!p || p >= endp-2)
 330                 break;
 331             *p++ = '\0';
 332             quote = *p++;
 333             value = p;
 334             p = strchr(p, quote);
 335             if (!p || p >= endp)
 336                 break;
 337             *p++ = '\0';
 338             PRINT(("NSV NSVf INFO: %s='%s'\n", token, value));
 339             if (!strcmp(token, "ASPECT")) {
 340                 /* don't care */
 341             } else if (!strcmp(token, "CREATOR") || !strcmp(token, "Author")) {
 342                 strncpy(s->author, value, 512-1);
 343             } else if (!strcmp(token, "Copyright")) {
 344                 strncpy(s->copyright, value, 512-1);
 345             } else if (!strcmp(token, "TITLE") || !strcmp(token, "Title")) {
 346                 strncpy(s->title, value, 512-1);
 347             }
 348         }
 349         av_free(strings);
 350     }
 351     if (url_feof(pb))
 352         return -1;
 353
 354     PRINT(("NSV got infos; filepos %"PRId64"\n", url_ftell(pb)));
 355
 356     if (table_entries_used > 0) {
 357         nsv->index_entries = table_entries_used;
 358         if((unsigned)table_entries >= UINT_MAX / sizeof(uint32_t))
 359             return -1;
 360         nsv->nsvf_index_data = av_malloc(table_entries * sizeof(uint32_t));
 361 #warning "FIXME: Byteswap buffer as needed"
 362         get_buffer(pb, (unsigned char *)nsv->nsvf_index_data, table_entries * sizeof(uint32_t));
 363     }
 364
 365     PRINT(("NSV got index; filepos %"PRId64"\n", url_ftell(pb)));
 366
 367 #ifdef DEBUG_DUMP_INDEX
 368 #define V(v) ((v<0x20 || v > 127)?'.':v)
 369     /* dump index */
 370     PRINT(("NSV %d INDEX ENTRIES:\n", table_entries));
 371     PRINT(("NSV [dataoffset][fileoffset]\n", table_entries));
 372     for (i = 0; i < table_entries; i++) {
 373         unsigned char b[8];
 374         url_fseek(pb, size + nsv->nsvf_index_data[i], SEEK_SET);
 375         get_buffer(pb, b, 8);
 376         PRINT(("NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
 377            "%c%c%c%c%c%c%c%c\n",
 378            nsv->nsvf_index_data[i], size + nsv->nsvf_index_data[i],
 379            b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
 380            V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) ));
 381     }
 382     //url_fseek(pb, size, SEEK_SET); /* go back to end of header */
 383 #undef V
 384 #endif
 385
 386     url_fseek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
 387
 388     if (url_feof(pb))
 389         return -1;
 390     nsv->state = NSV_HAS_READ_NSVF;
 391     return 0;
 392 }
 393
 394 static int nsv_parse_NSVs_header(AVFormatContext *s, AVFormatParameters *ap)
 395 {
 396     NSVContext *nsv = s->priv_data;
 397     ByteIOContext *pb = s->pb;
 398     uint32_t vtag, atag;
 399     uint16_t vwidth, vheight;
 400     AVRational framerate;
 401     int i;
 402     AVStream *st;
 403     NSVStream *nst;
 404     PRINT(("%s()\n", __FUNCTION__));
 405
 406     vtag = get_le32(pb);
 407     atag = get_le32(pb);
 408     vwidth = get_le16(pb);
 409     vheight = get_le16(pb);
 410     i = get_byte(pb);
 411
 412     PRINT(("NSV NSVs framerate code %2x\n", i));
 413     if(i&0x80) { /* odd way of giving native framerates from docs */
 414         int t=(i & 0x7F)>>2;
 415         if(t<16) framerate = (AVRational){1, t+1};
 416         else     framerate = (AVRational){t-15, 1};
 417
 418         if(i&1){
 419             framerate.num *= 1000;
 420             framerate.den *= 1001;
 421         }
 422
 423         if((i&3)==3)      framerate.num *= 24;
 424         else if((i&3)==2) framerate.num *= 25;
 425         else              framerate.num *= 30;
 426     }
 427     else
 428         framerate= (AVRational){i, 1};
 429
 430     nsv->avsync = get_le16(pb);
 431 #ifdef DEBUG
 432     print_tag("NSV NSVs vtag", vtag, 0);
 433     print_tag("NSV NSVs atag", atag, 0);
 434     PRINT(("NSV NSVs vsize %dx%d\n", vwidth, vheight));
 435 #endif
 436
 437     /* XXX change to ap != NULL ? */
 438     if (s->nb_streams == 0) { /* streams not yet published, let's do that */
 439         nsv->vtag = vtag;
 440         nsv->atag = atag;
 441         nsv->vwidth = vwidth;
 442         nsv->vheight = vwidth;
 443         if (vtag != T_NONE) {
 444             st = av_new_stream(s, NSV_ST_VIDEO);
 445             if (!st)
 446                 goto fail;
 447
 448             nst = av_mallocz(sizeof(NSVStream));
 449             if (!nst)
 450                 goto fail;
 451             st->priv_data = nst;
 452             st->codec->codec_type = CODEC_TYPE_VIDEO;
 453             st->codec->codec_tag = vtag;
 454             st->codec->codec_id = codec_get_id(nsv_codec_video_tags, vtag);
 455             st->codec->width = vwidth;
 456             st->codec->height = vheight;
 457             st->codec->bits_per_sample = 24; /* depth XXX */
 458
 459             av_set_pts_info(st, 64, framerate.den, framerate.num);
 460             st->start_time = 0;
 461             st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
 462         }
 463         if (atag != T_NONE) {
 464 #ifndef DISABLE_AUDIO
 465             st = av_new_stream(s, NSV_ST_AUDIO);
 466             if (!st)
 467                 goto fail;
 468
 469             nst = av_mallocz(sizeof(NSVStream));
 470             if (!nst)
 471                 goto fail;
 472             st->priv_data = nst;
 473             st->codec->codec_type = CODEC_TYPE_AUDIO;
 474             st->codec->codec_tag = atag;
 475             st->codec->codec_id = codec_get_id(nsv_codec_audio_tags, atag);
 476
 477             st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
 478
 479             /* set timebase to common denominator of ms and framerate */
 480             av_set_pts_info(st, 64, 1, framerate.num*1000);
 481             st->start_time = 0;
 482             st->duration = (int64_t)nsv->duration * framerate.num;
 483 #endif
 484         }
 485 #ifdef CHECK_SUBSEQUENT_NSVS
 486     } else {
 487         if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
 488             PRINT(("NSV NSVs header values differ from the first one!!!\n"));
 489             //return -1;
 490         }
 491 #endif /* CHECK_SUBSEQUENT_NSVS */
 492     }
 493
 494     nsv->state = NSV_HAS_READ_NSVS;
 495     return 0;
 496 fail:
 497     /* XXX */
 498     nsv->state = NSV_UNSYNC;
 499     return -1;
 500 }
 501
 502 static int nsv_read_header(AVFormatContext *s, AVFormatParameters *ap)
 503 {
 504     NSVContext *nsv = s->priv_data;
 505     int i, err;
 506
 507     PRINT(("%s()\n", __FUNCTION__));
 508     PRINT(("filename '%s'\n", s->filename));
 509
 510     nsv->state = NSV_UNSYNC;
 511     nsv->ahead[0].data = nsv->ahead[1].data = NULL;
 512
 513     for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
 514         if (nsv_resync(s) < 0)
 515             return -1;
 516         if (nsv->state == NSV_FOUND_NSVF)
 517             err = nsv_parse_NSVf_header(s, ap);
 518             /* we need the first NSVs also... */
 519         if (nsv->state == NSV_FOUND_NSVS) {
 520             err = nsv_parse_NSVs_header(s, ap);
 521             break; /* we just want the first one */
 522         }
 523     }
 524     if (s->nb_streams < 1) /* no luck so far */
 525         return -1;
 526     /* now read the first chunk, so we can attempt to decode more info */
 527     err = nsv_read_chunk(s, 1);
 528
 529     PRINT(("parsed header\n"));
 530     return 0;
 531 }
 532
 533 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
 534 {
 535     NSVContext *nsv = s->priv_data;
 536     ByteIOContext *pb = s->pb;
 537     AVStream *st[2] = {NULL, NULL};
 538     NSVStream *nst;
 539     AVPacket *pkt;
 540     int i, err = 0;
 541     uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
 542     uint32_t vsize;
 543     uint16_t asize;
 544     uint16_t auxsize;
 545     uint32_t auxtag;
 546
 547     PRINT(("%s(%d)\n", __FUNCTION__, fill_header));
 548
 549     if (nsv->ahead[0].data || nsv->ahead[1].data)
 550         return 0; //-1; /* hey! eat what you've in your plate first! */
 551
 552 null_chunk_retry:
 553     if (url_feof(pb))
 554         return -1;
 555
 556     for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
 557         err = nsv_resync(s);
 558     if (err < 0)
 559         return err;
 560     if (nsv->state == NSV_FOUND_NSVS)
 561         err = nsv_parse_NSVs_header(s, NULL);
 562     if (err < 0)
 563         return err;
 564     if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
 565         return -1;
 566
 567     auxcount = get_byte(pb);
 568     vsize = get_le16(pb);
 569     asize = get_le16(pb);
 570     vsize = (vsize << 4) | (auxcount >> 4);
 571     auxcount &= 0x0f;
 572     PRINT(("NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize));
 573     /* skip aux stuff */
 574     for (i = 0; i < auxcount; i++) {
 575         auxsize = get_le16(pb);
 576         auxtag = get_le32(pb);
 577         PRINT(("NSV aux data: '%c%c%c%c', %d bytes\n",
 578               (auxtag & 0x0ff),
 579               ((auxtag >> 8) & 0x0ff),
 580               ((auxtag >> 16) & 0x0ff),
 581               ((auxtag >> 24) & 0x0ff),
 582               auxsize));
 583         url_fskip(pb, auxsize);
 584         vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
 585     }
 586
 587     if (url_feof(pb))
 588         return -1;
 589     if (!vsize && !asize) {
 590         nsv->state = NSV_UNSYNC;
 591         goto null_chunk_retry;
 592     }
 593
 594     /* map back streams to v,a */
 595     if (s->streams[0])
 596         st[s->streams[0]->id] = s->streams[0];
 597     if (s->streams[1])
 598         st[s->streams[1]->id] = s->streams[1];
 599
 600     if (vsize/* && st[NSV_ST_VIDEO]*/) {
 601         nst = st[NSV_ST_VIDEO]->priv_data;
 602         pkt = &nsv->ahead[NSV_ST_VIDEO];
 603         av_get_packet(pb, pkt, vsize);
 604         pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
 605         pkt->dts = nst->frame_offset;
 606         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
 607 /*
 608         for (i = 0; i < MIN(8, vsize); i++)
 609             PRINT(("NSV video: [%d] = %02x\n", i, pkt->data[i]));
 610 */
 611     }
 612     if(st[NSV_ST_VIDEO])
 613         ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
 614
 615     if (asize/*st[NSV_ST_AUDIO]*/) {
 616         nst = st[NSV_ST_AUDIO]->priv_data;
 617         pkt = &nsv->ahead[NSV_ST_AUDIO];
 618         /* read raw audio specific header on the first audio chunk... */
 619         /* on ALL audio chunks ?? seems so! */
 620         if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
 621             uint8_t bps;
 622             uint8_t channels;
 623             uint16_t samplerate;
 624             bps = get_byte(pb);
 625             channels = get_byte(pb);
 626             samplerate = get_le16(pb);
 627             asize-=4;
 628             PRINT(("NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate));
 629             if (fill_header) {
 630                 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
 631                 if (bps != 16) {
 632                     PRINT(("NSV AUDIO bit/sample != 16 (%d)!!!\n", bps));
 633                 }
 634                 bps /= channels; // ???
 635                 if (bps == 8)
 636                     st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
 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                 PRINT(("NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate));
 642             }
 643         }
 644         av_get_packet(pb, pkt, asize);
 645         pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
 646         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
 647         if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
 648             /* on a nsvs frame we have new information on a/v sync */
 649             pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
 650             pkt->dts *= (int64_t)1000 * st[NSV_ST_VIDEO]->time_base.num;
 651             pkt->dts += (int64_t)nsv->avsync * st[NSV_ST_VIDEO]->time_base.den;
 652             PRINT(("NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts));
 653         }
 654         nst->frame_offset++;
 655     }
 656
 657     nsv->state = NSV_UNSYNC;
 658     return 0;
 659 }
 660
 661
 662 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
 663 {
 664     NSVContext *nsv = s->priv_data;
 665     int i, err = 0;
 666
 667     PRINT(("%s()\n", __FUNCTION__));
 668
 669     /* in case we don't already have something to eat ... */
 670     if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
 671         err = nsv_read_chunk(s, 0);
 672     if (err < 0)
 673         return err;
 674
 675     /* now pick one of the plates */
 676     for (i = 0; i < 2; i++) {
 677         if (nsv->ahead[i].data) {
 678                 PRINT(("%s: using cached packet[%d]\n", __FUNCTION__, i));
 679             /* avoid the cost of new_packet + memcpy(->data) */
 680             memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
 681             nsv->ahead[i].data = NULL; /* we ate that one */
 682             return pkt->size;
 683         }
 684     }
 685
 686     /* this restaurant is not approvisionned :^] */
 687     return -1;
 688 }
 689
 690 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
 691 {
 692 #if 0
 693     NSVContext *avi = s->priv_data;
 694     AVStream *st;
 695     NSVStream *ast;
 696     int frame_number, i;
 697     int64_t pos;
 698 #endif
 699
 700     return -1;
 701 }
 702
 703 static int nsv_read_close(AVFormatContext *s)
 704 {
 705 /*     int i; */
 706     NSVContext *nsv = s->priv_data;
 707
 708     if (nsv->index_entries)
 709         av_free(nsv->nsvf_index_data);
 710
 711 #if 0
 712
 713     for(i=0;i<s->nb_streams;i++) {
 714         AVStream *st = s->streams[i];
 715         NSVStream *ast = st->priv_data;
 716         if(ast){
 717             av_free(ast->index_entries);
 718             av_free(ast);
 719         }
 720         av_free(st->codec->palctrl);
 721     }
 722
 723 #endif
 724     return 0;
 725 }
 726
 727 static int nsv_probe(AVProbeData *p)
 728 {
 729     int i;
 730 //    PRINT(("nsv_probe(), buf_size %d\n", p->buf_size));
 731     /* check file header */
 732     /* streamed files might not have any header */
 733     if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
 734         p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
 735         return AVPROBE_SCORE_MAX;
 736     /* XXX: do streamed files always start at chunk boundary ?? */
 737     /* or do we need to search NSVs in the byte stream ? */
 738     /* seems the servers don't bother starting clean chunks... */
 739     /* sometimes even the first header is at 9KB or something :^) */
 740     for (i = 1; i < p->buf_size - 3; i++) {
 741         if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
 742             p->buf[i+2] == 'V' && p->buf[i+3] == 's')
 743             return AVPROBE_SCORE_MAX-20;
 744     }
 745     /* so we'll have more luck on extension... */
 746     if (match_ext(p->filename, "nsv"))
 747         return AVPROBE_SCORE_MAX/2;
 748     /* FIXME: add mime-type check */
 749     return 0;
 750 }
 751
 752 AVInputFormat nsv_demuxer = {
 753     "nsv",
 754     NULL_IF_CONFIG_SMALL("NullSoft Video format"),
 755     sizeof(NSVContext),
 756     nsv_probe,
 757     nsv_read_header,
 758     nsv_read_packet,
 759     nsv_read_close,
 760     nsv_read_seek,
 761 };