libavformat/nsvdec.c

   1 /*
   2  * NSV demuxer
   3  * Copyright (c) 2004 The Libav Project
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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
  28 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
  29 #define CHECK_SUBSEQUENT_NSVS
  30 //#define DISABLE_AUDIO
  31
  32 /* max bytes to crawl for trying to resync
  33  * stupid streaming servers don't start at chunk boundaries...
  34  */
  35 #define NSV_MAX_RESYNC (500*1024)
  36 #define NSV_MAX_RESYNC_TRIES 300
  37
  38 /*
  39  * First version by Francois Revol - revol@free.fr
  40  * References:
  41  * (1) http://www.multimedia.cx/nsv-format.txt
  42  * seems someone came to the same conclusions as me, and updated it:
  43  * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
  44  *     http://www.stud.ktu.lt/~vitslav/nsv/
  45  * official docs
  46  * (3) http://ultravox.aol.com/NSVFormat.rtf
  47  * Sample files:
  48  * (S1) http://www.nullsoft.com/nsv/samples/
  49  * http://www.nullsoft.com/nsv/samples/faster.nsv
  50  * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
  51  */
  52
  53 /*
  54  * notes on the header (Francois Revol):
  55  *
  56  * It is followed by strings, then a table, but nothing tells
  57  * where the table begins according to (1). After checking faster.nsv,
  58  * I believe NVSf[16-19] gives the size of the strings data
  59  * (that is the offset of the data table after the header).
  60  * After checking all samples from (S1) all confirms this.
  61  *
  62  * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
  63  * I noticed there was about 1 NVSs chunk/s, so I ran
  64  * strings faster.nsv | grep NSVs | wc -l
  65  * which gave me 180. That leads me to think that NSVf[12-15] might be the
  66  * file length in milliseconds.
  67  * Let's try that:
  68  * 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
  69  * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
  70  *
  71  * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
  72  * so the header seems to not be mandatory. (for streaming).
  73  *
  74  * index slice duration check (excepts nsvtrailer.nsv):
  75  * for f in [^n]*.nsv; do
  76  *     DUR="$(avconv -i "$f" 2> /dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"
  77  *     IC="$(avconv -i "$f" 2> /dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"
  78  *     echo "duration $DUR, slite time $(($DUR/$IC))"
  79  * done
  80  */
  81
  82 /*
  83  * TODO:
  84  * - handle timestamps !!!
  85  * - use index
  86  * - mime-type in probe()
  87  * - seek
  88  */
  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 *nsvs_file_offset;
 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     AVRational framerate;
 184     uint32_t *nsvs_timestamps;
 185     //DVDemuxContext* dv_demux;
 186 } NSVContext;
 187
 188 static const AVCodecTag nsv_codec_video_tags[] = {
 189     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
 190     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
 191     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
 192     { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
 193     { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
 194     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
 195     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
 196     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
 197     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
 198 /*
 199     { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
 200     { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
 201 */
 202     { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
 203     { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
 204     { AV_CODEC_ID_NONE, 0 },
 205 };
 206
 207 static const AVCodecTag nsv_codec_audio_tags[] = {
 208     { AV_CODEC_ID_MP3,       MKTAG('M', 'P', '3', ' ') },
 209     { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', ' ') },
 210     { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', 'P') },
 211     { AV_CODEC_ID_SPEEX,     MKTAG('S', 'P', 'X', ' ') },
 212     { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
 213     { AV_CODEC_ID_NONE,      0 },
 214 };
 215
 216 //static int nsv_load_index(AVFormatContext *s);
 217 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
 218
 219 #define print_tag(str, tag, size)       \
 220     av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
 221             str, tag & 0xff,            \
 222             (tag >> 8) & 0xff,          \
 223             (tag >> 16) & 0xff,         \
 224             (tag >> 24) & 0xff);
 225
 226 /* try to find something we recognize, and set the state accordingly */
 227 static int nsv_resync(AVFormatContext *s)
 228 {
 229     NSVContext *nsv = s->priv_data;
 230     AVIOContext *pb = s->pb;
 231     uint32_t v = 0;
 232     int i;
 233
 234     av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
 235
 236     //nsv->state = NSV_UNSYNC;
 237
 238     for (i = 0; i < NSV_MAX_RESYNC; i++) {
 239         if (pb->eof_reached) {
 240             av_dlog(s, "NSV EOF\n");
 241             nsv->state = NSV_UNSYNC;
 242             return -1;
 243         }
 244         v <<= 8;
 245         v |= avio_r8(pb);
 246         if (i < 8) {
 247             av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
 248         }
 249
 250         if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
 251             av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
 252             nsv->state = NSV_FOUND_BEEF;
 253             return 0;
 254         }
 255         /* we read as big-endian, thus the MK*BE* */
 256         if (v == TB_NSVF) { /* NSVf */
 257             av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
 258             nsv->state = NSV_FOUND_NSVF;
 259             return 0;
 260         }
 261         if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
 262             av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
 263             nsv->state = NSV_FOUND_NSVS;
 264             return 0;
 265         }
 266
 267     }
 268     av_dlog(s, "NSV sync lost\n");
 269     return -1;
 270 }
 271
 272 static int nsv_parse_NSVf_header(AVFormatContext *s)
 273 {
 274     NSVContext *nsv = s->priv_data;
 275     AVIOContext *pb = s->pb;
 276     unsigned int av_unused file_size;
 277     unsigned int size;
 278     int64_t duration;
 279     int strings_size;
 280     int table_entries;
 281     int table_entries_used;
 282
 283     av_dlog(s, "%s()\n", __FUNCTION__);
 284
 285     nsv->state = NSV_UNSYNC; /* in case we fail */
 286
 287     size = avio_rl32(pb);
 288     if (size < 28)
 289         return -1;
 290     nsv->NSVf_end = size;
 291
 292     //s->file_size = (uint32_t)avio_rl32(pb);
 293     file_size = (uint32_t)avio_rl32(pb);
 294     av_dlog(s, "NSV NSVf chunk_size %u\n", size);
 295     av_dlog(s, "NSV NSVf file_size %u\n", file_size);
 296
 297     nsv->duration = duration = avio_rl32(pb); /* in ms */
 298     av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
 299     // XXX: store it in AVStreams
 300
 301     strings_size = avio_rl32(pb);
 302     table_entries = avio_rl32(pb);
 303     table_entries_used = avio_rl32(pb);
 304     av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
 305             strings_size, table_entries, table_entries_used);
 306     if (pb->eof_reached)
 307         return -1;
 308
 309     av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
 310
 311     if (strings_size > 0) {
 312         char *strings; /* last byte will be '\0' to play safe with str*() */
 313         char *p, *endp;
 314         char *token, *value;
 315         char quote;
 316
 317         p = strings = av_mallocz((size_t)strings_size + 1);
 318         if (!p)
 319             return AVERROR(ENOMEM);
 320         endp = strings + strings_size;
 321         avio_read(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             av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
 339             av_dict_set(&s->metadata, token, value, 0);
 340         }
 341         av_free(strings);
 342     }
 343     if (pb->eof_reached)
 344         return -1;
 345
 346     av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
 347
 348     if (table_entries_used > 0) {
 349         int i;
 350         nsv->index_entries = table_entries_used;
 351         if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
 352             return -1;
 353         nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
 354         if (!nsv->nsvs_file_offset)
 355             return AVERROR(ENOMEM);
 356
 357         for(i=0;i<table_entries_used;i++)
 358             nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
 359
 360         if(table_entries > table_entries_used &&
 361            avio_rl32(pb) == MKTAG('T','O','C','2')) {
 362             nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
 363             if (!nsv->nsvs_timestamps)
 364                 return AVERROR(ENOMEM);
 365             for(i=0;i<table_entries_used;i++) {
 366                 nsv->nsvs_timestamps[i] = avio_rl32(pb);
 367             }
 368         }
 369     }
 370
 371     av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
 372
 373 #ifdef DEBUG_DUMP_INDEX
 374 #define V(v) ((v<0x20 || v > 127)?'.':v)
 375     /* dump index */
 376     av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
 377     av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
 378     for (i = 0; i < table_entries; i++) {
 379         unsigned char b[8];
 380         avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
 381         avio_read(pb, b, 8);
 382         av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
 383            "%c%c%c%c%c%c%c%c\n",
 384            nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
 385            b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
 386            V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
 387     }
 388     //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
 389 #undef V
 390 #endif
 391
 392     avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
 393
 394     if (pb->eof_reached)
 395         return -1;
 396     nsv->state = NSV_HAS_READ_NSVF;
 397     return 0;
 398 }
 399
 400 static int nsv_parse_NSVs_header(AVFormatContext *s)
 401 {
 402     NSVContext *nsv = s->priv_data;
 403     AVIOContext *pb = s->pb;
 404     uint32_t vtag, atag;
 405     uint16_t vwidth, vheight;
 406     AVRational framerate;
 407     int i;
 408     AVStream *st;
 409     NSVStream *nst;
 410     av_dlog(s, "%s()\n", __FUNCTION__);
 411
 412     vtag = avio_rl32(pb);
 413     atag = avio_rl32(pb);
 414     vwidth = avio_rl16(pb);
 415     vheight = avio_rl16(pb);
 416     i = avio_r8(pb);
 417
 418     av_dlog(s, "NSV NSVs framerate code %2x\n", i);
 419     if(i&0x80) { /* odd way of giving native framerates from docs */
 420         int t=(i & 0x7F)>>2;
 421         if(t<16) framerate = (AVRational){1, t+1};
 422         else     framerate = (AVRational){t-15, 1};
 423
 424         if(i&1){
 425             framerate.num *= 1000;
 426             framerate.den *= 1001;
 427         }
 428
 429         if((i&3)==3)      framerate.num *= 24;
 430         else if((i&3)==2) framerate.num *= 25;
 431         else              framerate.num *= 30;
 432     }
 433     else
 434         framerate= (AVRational){i, 1};
 435
 436     nsv->avsync = avio_rl16(pb);
 437     nsv->framerate = framerate;
 438
 439     print_tag("NSV NSVs vtag", vtag, 0);
 440     print_tag("NSV NSVs atag", atag, 0);
 441     av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
 442
 443     /* XXX change to ap != NULL ? */
 444     if (s->nb_streams == 0) { /* streams not yet published, let's do that */
 445         nsv->vtag = vtag;
 446         nsv->atag = atag;
 447         nsv->vwidth = vwidth;
 448         nsv->vheight = vwidth;
 449         if (vtag != T_NONE) {
 450             int i;
 451             st = avformat_new_stream(s, NULL);
 452             if (!st)
 453                 goto fail;
 454
 455             st->id = NSV_ST_VIDEO;
 456             nst = av_mallocz(sizeof(NSVStream));
 457             if (!nst)
 458                 goto fail;
 459             st->priv_data = nst;
 460             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 461             st->codec->codec_tag = vtag;
 462             st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
 463             st->codec->width = vwidth;
 464             st->codec->height = vheight;
 465             st->codec->bits_per_coded_sample = 24; /* depth XXX */
 466
 467             avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
 468             st->start_time = 0;
 469             st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
 470
 471             for(i=0;i<nsv->index_entries;i++) {
 472                 if(nsv->nsvs_timestamps) {
 473                     av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
 474                                        0, 0, AVINDEX_KEYFRAME);
 475                 } else {
 476                     int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
 477                     av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
 478                 }
 479             }
 480         }
 481         if (atag != T_NONE) {
 482 #ifndef DISABLE_AUDIO
 483             st = avformat_new_stream(s, NULL);
 484             if (!st)
 485                 goto fail;
 486
 487             st->id = NSV_ST_AUDIO;
 488             nst = av_mallocz(sizeof(NSVStream));
 489             if (!nst)
 490                 goto fail;
 491             st->priv_data = nst;
 492             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 493             st->codec->codec_tag = atag;
 494             st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
 495
 496             st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
 497
 498             /* set timebase to common denominator of ms and framerate */
 499             avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
 500             st->start_time = 0;
 501             st->duration = (int64_t)nsv->duration * framerate.num;
 502 #endif
 503         }
 504 #ifdef CHECK_SUBSEQUENT_NSVS
 505     } else {
 506         if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
 507             av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
 508             //return -1;
 509         }
 510 #endif /* CHECK_SUBSEQUENT_NSVS */
 511     }
 512
 513     nsv->state = NSV_HAS_READ_NSVS;
 514     return 0;
 515 fail:
 516     /* XXX */
 517     nsv->state = NSV_UNSYNC;
 518     return -1;
 519 }
 520
 521 static int nsv_read_header(AVFormatContext *s)
 522 {
 523     NSVContext *nsv = s->priv_data;
 524     int i, err;
 525
 526     av_dlog(s, "%s()\n", __FUNCTION__);
 527     av_dlog(s, "filename '%s'\n", s->filename);
 528
 529     nsv->state = NSV_UNSYNC;
 530     nsv->ahead[0].data = nsv->ahead[1].data = NULL;
 531
 532     for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
 533         if (nsv_resync(s) < 0)
 534             return -1;
 535         if (nsv->state == NSV_FOUND_NSVF) {
 536             err = nsv_parse_NSVf_header(s);
 537             if (err < 0)
 538                 return err;
 539         }
 540             /* we need the first NSVs also... */
 541         if (nsv->state == NSV_FOUND_NSVS) {
 542             err = nsv_parse_NSVs_header(s);
 543             if (err < 0)
 544                 return err;
 545             break; /* we just want the first one */
 546         }
 547     }
 548     if (s->nb_streams < 1) /* no luck so far */
 549         return -1;
 550     /* now read the first chunk, so we can attempt to decode more info */
 551     err = nsv_read_chunk(s, 1);
 552
 553     av_dlog(s, "parsed header\n");
 554     return err;
 555 }
 556
 557 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
 558 {
 559     NSVContext *nsv = s->priv_data;
 560     AVIOContext *pb = s->pb;
 561     AVStream *st[2] = {NULL, NULL};
 562     NSVStream *nst;
 563     AVPacket *pkt;
 564     int i, err = 0;
 565     uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
 566     uint32_t vsize;
 567     uint16_t asize;
 568     uint16_t auxsize;
 569
 570     av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
 571
 572     if (nsv->ahead[0].data || nsv->ahead[1].data)
 573         return 0; //-1; /* hey! eat what you've in your plate first! */
 574
 575 null_chunk_retry:
 576     if (pb->eof_reached)
 577         return -1;
 578
 579     for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
 580         err = nsv_resync(s);
 581     if (err < 0)
 582         return err;
 583     if (nsv->state == NSV_FOUND_NSVS)
 584         err = nsv_parse_NSVs_header(s);
 585     if (err < 0)
 586         return err;
 587     if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
 588         return -1;
 589
 590     auxcount = avio_r8(pb);
 591     vsize = avio_rl16(pb);
 592     asize = avio_rl16(pb);
 593     vsize = (vsize << 4) | (auxcount >> 4);
 594     auxcount &= 0x0f;
 595     av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
 596     /* skip aux stuff */
 597     for (i = 0; i < auxcount; i++) {
 598         uint32_t av_unused auxtag;
 599         auxsize = avio_rl16(pb);
 600         auxtag = avio_rl32(pb);
 601         av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
 602               (auxtag & 0x0ff),
 603               ((auxtag >> 8) & 0x0ff),
 604               ((auxtag >> 16) & 0x0ff),
 605               ((auxtag >> 24) & 0x0ff),
 606               auxsize);
 607         avio_skip(pb, auxsize);
 608         vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
 609     }
 610
 611     if (pb->eof_reached)
 612         return -1;
 613     if (!vsize && !asize) {
 614         nsv->state = NSV_UNSYNC;
 615         goto null_chunk_retry;
 616     }
 617
 618     /* map back streams to v,a */
 619     if (s->nb_streams > 0)
 620         st[s->streams[0]->id] = s->streams[0];
 621     if (s->nb_streams > 1)
 622         st[s->streams[1]->id] = s->streams[1];
 623
 624     if (vsize && st[NSV_ST_VIDEO]) {
 625         nst = st[NSV_ST_VIDEO]->priv_data;
 626         pkt = &nsv->ahead[NSV_ST_VIDEO];
 627         av_get_packet(pb, pkt, vsize);
 628         pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
 629         pkt->dts = nst->frame_offset;
 630         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
 631         for (i = 0; i < FFMIN(8, vsize); i++)
 632             av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
 633     }
 634     if(st[NSV_ST_VIDEO])
 635         ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
 636
 637     if (asize && st[NSV_ST_AUDIO]) {
 638         nst = st[NSV_ST_AUDIO]->priv_data;
 639         pkt = &nsv->ahead[NSV_ST_AUDIO];
 640         /* read raw audio specific header on the first audio chunk... */
 641         /* on ALL audio chunks ?? seems so! */
 642         if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
 643             uint8_t bps;
 644             uint8_t channels;
 645             uint16_t samplerate;
 646             bps = avio_r8(pb);
 647             channels = avio_r8(pb);
 648             samplerate = avio_rl16(pb);
 649             asize-=4;
 650             av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
 651             if (fill_header) {
 652                 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
 653                 if (bps != 16) {
 654                     av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
 655                 }
 656                 bps /= channels; // ???
 657                 if (bps == 8)
 658                     st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8;
 659                 samplerate /= 4;/* UGH ??? XXX */
 660                 channels = 1;
 661                 st[NSV_ST_AUDIO]->codec->channels = channels;
 662                 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
 663                 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
 664             }
 665         }
 666         av_get_packet(pb, pkt, asize);
 667         pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
 668         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
 669         if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
 670             /* on a nsvs frame we have new information on a/v sync */
 671             pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
 672             pkt->dts *= (int64_t)1000        * nsv->framerate.den;
 673             pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
 674             av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
 675         }
 676         nst->frame_offset++;
 677     }
 678
 679     nsv->state = NSV_UNSYNC;
 680     return 0;
 681 }
 682
 683
 684 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
 685 {
 686     NSVContext *nsv = s->priv_data;
 687     int i, err = 0;
 688
 689     av_dlog(s, "%s()\n", __FUNCTION__);
 690
 691     /* in case we don't already have something to eat ... */
 692     if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
 693         err = nsv_read_chunk(s, 0);
 694     if (err < 0)
 695         return err;
 696
 697     /* now pick one of the plates */
 698     for (i = 0; i < 2; i++) {
 699         if (nsv->ahead[i].data) {
 700             av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
 701             /* avoid the cost of new_packet + memcpy(->data) */
 702             memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
 703             nsv->ahead[i].data = NULL; /* we ate that one */
 704             return pkt->size;
 705         }
 706     }
 707
 708     /* this restaurant is not approvisionned :^] */
 709     return -1;
 710 }
 711
 712 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
 713 {
 714     NSVContext *nsv = s->priv_data;
 715     AVStream *st = s->streams[stream_index];
 716     NSVStream *nst = st->priv_data;
 717     int index;
 718
 719     index = av_index_search_timestamp(st, timestamp, flags);
 720     if(index < 0)
 721         return -1;
 722
 723     if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
 724         return -1;
 725
 726     nst->frame_offset = st->index_entries[index].timestamp;
 727     nsv->state = NSV_UNSYNC;
 728     return 0;
 729 }
 730
 731 static int nsv_read_close(AVFormatContext *s)
 732 {
 733 /*     int i; */
 734     NSVContext *nsv = s->priv_data;
 735
 736     av_freep(&nsv->nsvs_file_offset);
 737     av_freep(&nsv->nsvs_timestamps);
 738     if (nsv->ahead[0].data)
 739         av_free_packet(&nsv->ahead[0]);
 740     if (nsv->ahead[1].data)
 741         av_free_packet(&nsv->ahead[1]);
 742
 743 #if 0
 744
 745     for(i=0;i<s->nb_streams;i++) {
 746         AVStream *st = s->streams[i];
 747         NSVStream *ast = st->priv_data;
 748         if(ast){
 749             av_free(ast->index_entries);
 750             av_free(ast);
 751         }
 752         av_free(st->codec->palctrl);
 753     }
 754
 755 #endif
 756     return 0;
 757 }
 758
 759 static int nsv_probe(AVProbeData *p)
 760 {
 761     int i;
 762     int score;
 763     int vsize, asize, auxcount;
 764     score = 0;
 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 (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
 777             p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
 778             score = AVPROBE_SCORE_MAX/5;
 779             /* Get the chunk size and check if at the end we are getting 0xBEEF */
 780             auxcount = p->buf[i+19];
 781             vsize = p->buf[i+20]  | p->buf[i+21] << 8;
 782             asize = p->buf[i+22]  | p->buf[i+23] << 8;
 783             vsize = (vsize << 4) | (auxcount >> 4);
 784             if ((asize + vsize + i + 23) <  p->buf_size - 2) {
 785                 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
 786                     p->buf[i+23+asize+vsize+2] == 0xBE)
 787                     return AVPROBE_SCORE_MAX-20;
 788             }
 789         }
 790     }
 791     /* so we'll have more luck on extension... */
 792     if (av_match_ext(p->filename, "nsv"))
 793         return AVPROBE_SCORE_MAX/2;
 794     /* FIXME: add mime-type check */
 795     return score;
 796 }
 797
 798 AVInputFormat ff_nsv_demuxer = {
 799     .name           = "nsv",
 800     .long_name      = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
 801     .priv_data_size = sizeof(NSVContext),
 802     .read_probe     = nsv_probe,
 803     .read_header    = nsv_read_header,
 804     .read_packet    = nsv_read_packet,
 805     .read_close     = nsv_read_close,
 806     .read_seek      = nsv_read_seek,
 807 };