3 * Copyright (c) 2004 The Libav Project
5 * This file is part of Libav.
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.
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.
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
22 #include "libavutil/mathematics.h"
25 #include "libavutil/dict.h"
27 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
28 #define CHECK_SUBSEQUENT_NSVS
29 //#define DISABLE_AUDIO
31 /* max bytes to crawl for trying to resync
32 * stupid streaming servers don't start at chunk boundaries...
34 #define NSV_MAX_RESYNC (500*1024)
35 #define NSV_MAX_RESYNC_TRIES 300
38 * First version by Francois Revol - revol@free.fr
40 * (1) http://www.multimedia.cx/nsv-format.txt
41 * seems someone came to the same conclusions as me, and updated it:
42 * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
43 * http://www.stud.ktu.lt/~vitslav/nsv/
45 * (3) http://ultravox.aol.com/NSVFormat.rtf
47 * (S1) http://www.nullsoft.com/nsv/samples/
48 * http://www.nullsoft.com/nsv/samples/faster.nsv
49 * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
53 * notes on the header (Francois Revol):
55 * It is followed by strings, then a table, but nothing tells
56 * where the table begins according to (1). After checking faster.nsv,
57 * I believe NVSf[16-19] gives the size of the strings data
58 * (that is the offset of the data table after the header).
59 * After checking all samples from (S1) all confirms this.
61 * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
62 * I noticed there was about 1 NVSs chunk/s, so I ran
63 * strings faster.nsv | grep NSVs | wc -l
64 * which gave me 180. That leads me to think that NSVf[12-15] might be the
65 * file length in milliseconds.
67 * 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
68 * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
70 * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
71 * so the header seems to not be mandatory. (for streaming).
73 * index slice duration check (excepts nsvtrailer.nsv):
74 * for f in [^n]*.nsv; do
75 * DUR="$(avconv -i "$f" 2> /dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"
76 * IC="$(avconv -i "$f" 2> /dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"
77 * echo "duration $DUR, slite time $(($DUR/$IC))"
83 * - handle timestamps !!!
85 * - mime-type in probe()
91 uint32_t chunk_tag; /* 'NSVf' */
93 uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
94 uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
95 uint32_t info_strings_size; /* size of the info strings */ //unknown2;
96 uint32_t table_entries;
97 uint32_t table_entries_used; /* the left ones should be -1 */
101 uint32_t chunk_tag; /* 'NSVs' */
102 uint32_t v4cc; /* or 'NONE' */
103 uint32_t a4cc; /* or 'NONE' */
104 uint16_t vwidth; /* assert(vwidth%16==0) */
105 uint16_t vheight; /* assert(vheight%16==0) */
106 uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
110 struct nsv_avchunk_header {
111 uint8_t vchunk_size_lsb;
112 uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
113 uint16_t achunk_size;
116 struct nsv_pcm_header {
117 uint8_t bits_per_sample;
118 uint8_t channel_count;
119 uint16_t sample_rate;
123 /* variation from avi.h */
124 /*typedef struct CodecTag {
131 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
132 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
133 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
134 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
135 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
136 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
137 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
139 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
140 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
142 /* hardcoded stream indexes */
143 #define NSV_ST_VIDEO 0
144 #define NSV_ST_AUDIO 1
145 #define NSV_ST_SUBT 2
158 typedef struct NSVStream {
159 int frame_offset; /* current frame (video) or byte (audio) counter
160 (used to compute the pts) */
163 int sample_size; /* audio only data */
166 int new_frame_offset; /* temporary storage (used during seek) */
167 int cum_len; /* temporary storage (used during seek) */
173 uint32_t *nsvs_file_offset;
175 enum NSVStatus state;
176 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
180 uint16_t vwidth, vheight;
182 AVRational framerate;
183 uint32_t *nsvs_timestamps;
184 //DVDemuxContext* dv_demux;
187 static const AVCodecTag nsv_codec_video_tags[] = {
188 { CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
189 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
190 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
191 { CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
192 { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
193 { CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
194 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
195 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
196 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
198 { CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
199 { CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
201 { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
202 { CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
203 { CODEC_ID_NONE, 0 },
206 static const AVCodecTag nsv_codec_audio_tags[] = {
207 { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
208 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
209 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
210 { CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
211 { CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
212 { CODEC_ID_NONE, 0 },
215 //static int nsv_load_index(AVFormatContext *s);
216 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
218 #define print_tag(str, tag, size) \
219 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
222 (tag >> 16) & 0xff, \
225 /* try to find something we recognize, and set the state accordingly */
226 static int nsv_resync(AVFormatContext *s)
228 NSVContext *nsv = s->priv_data;
229 AVIOContext *pb = s->pb;
233 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
235 //nsv->state = NSV_UNSYNC;
237 for (i = 0; i < NSV_MAX_RESYNC; i++) {
238 if (pb->eof_reached) {
239 av_dlog(s, "NSV EOF\n");
240 nsv->state = NSV_UNSYNC;
246 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
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;
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;
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;
267 av_dlog(s, "NSV sync lost\n");
271 static int nsv_parse_NSVf_header(AVFormatContext *s, AVFormatParameters *ap)
273 NSVContext *nsv = s->priv_data;
274 AVIOContext *pb = s->pb;
275 unsigned int av_unused file_size;
280 int table_entries_used;
282 av_dlog(s, "%s()\n", __FUNCTION__);
284 nsv->state = NSV_UNSYNC; /* in case we fail */
286 size = avio_rl32(pb);
289 nsv->NSVf_end = size;
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);
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
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);
308 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
310 if (strings_size > 0) {
311 char *strings; /* last byte will be '\0' to play safe with str*() */
316 p = strings = av_mallocz(strings_size + 1);
317 endp = strings + strings_size;
318 avio_read(pb, strings, strings_size);
321 p++; /* strip out spaces */
326 if (!p || p >= endp-2)
331 p = strchr(p, quote);
335 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
336 av_dict_set(&s->metadata, token, value, 0);
343 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
345 if (table_entries_used > 0) {
347 nsv->index_entries = table_entries_used;
348 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
350 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
352 for(i=0;i<table_entries_used;i++)
353 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
355 if(table_entries > table_entries_used &&
356 avio_rl32(pb) == MKTAG('T','O','C','2')) {
357 nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
358 for(i=0;i<table_entries_used;i++) {
359 nsv->nsvs_timestamps[i] = avio_rl32(pb);
364 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
366 #ifdef DEBUG_DUMP_INDEX
367 #define V(v) ((v<0x20 || v > 127)?'.':v)
369 av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
370 av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
371 for (i = 0; i < table_entries; i++) {
373 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
375 av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
376 "%c%c%c%c%c%c%c%c\n",
377 nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
378 b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
379 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 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
385 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
389 nsv->state = NSV_HAS_READ_NSVF;
393 static int nsv_parse_NSVs_header(AVFormatContext *s, AVFormatParameters *ap)
395 NSVContext *nsv = s->priv_data;
396 AVIOContext *pb = s->pb;
398 uint16_t vwidth, vheight;
399 AVRational framerate;
403 av_dlog(s, "%s()\n", __FUNCTION__);
405 vtag = avio_rl32(pb);
406 atag = avio_rl32(pb);
407 vwidth = avio_rl16(pb);
408 vheight = avio_rl16(pb);
411 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
412 if(i&0x80) { /* odd way of giving native framerates from docs */
414 if(t<16) framerate = (AVRational){1, t+1};
415 else framerate = (AVRational){t-15, 1};
418 framerate.num *= 1000;
419 framerate.den *= 1001;
422 if((i&3)==3) framerate.num *= 24;
423 else if((i&3)==2) framerate.num *= 25;
424 else framerate.num *= 30;
427 framerate= (AVRational){i, 1};
429 nsv->avsync = avio_rl16(pb);
430 nsv->framerate = framerate;
432 print_tag("NSV NSVs vtag", vtag, 0);
433 print_tag("NSV NSVs atag", atag, 0);
434 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
436 /* XXX change to ap != NULL ? */
437 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
440 nsv->vwidth = vwidth;
441 nsv->vheight = vwidth;
442 if (vtag != T_NONE) {
444 st = avformat_new_stream(s, NULL);
448 st->id = NSV_ST_VIDEO;
449 nst = av_mallocz(sizeof(NSVStream));
453 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
454 st->codec->codec_tag = vtag;
455 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
456 st->codec->width = vwidth;
457 st->codec->height = vheight;
458 st->codec->bits_per_coded_sample = 24; /* depth XXX */
460 av_set_pts_info(st, 64, framerate.den, framerate.num);
462 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
464 for(i=0;i<nsv->index_entries;i++) {
465 if(nsv->nsvs_timestamps) {
466 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
467 0, 0, AVINDEX_KEYFRAME);
469 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
470 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
474 if (atag != T_NONE) {
475 #ifndef DISABLE_AUDIO
476 st = avformat_new_stream(s, NULL);
480 st->id = NSV_ST_AUDIO;
481 nst = av_mallocz(sizeof(NSVStream));
485 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
486 st->codec->codec_tag = atag;
487 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
489 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
491 /* set timebase to common denominator of ms and framerate */
492 av_set_pts_info(st, 64, 1, framerate.num*1000);
494 st->duration = (int64_t)nsv->duration * framerate.num;
497 #ifdef CHECK_SUBSEQUENT_NSVS
499 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
500 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
503 #endif /* CHECK_SUBSEQUENT_NSVS */
506 nsv->state = NSV_HAS_READ_NSVS;
510 nsv->state = NSV_UNSYNC;
514 static int nsv_read_header(AVFormatContext *s, AVFormatParameters *ap)
516 NSVContext *nsv = s->priv_data;
519 av_dlog(s, "%s()\n", __FUNCTION__);
520 av_dlog(s, "filename '%s'\n", s->filename);
522 nsv->state = NSV_UNSYNC;
523 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
525 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
526 if (nsv_resync(s) < 0)
528 if (nsv->state == NSV_FOUND_NSVF)
529 err = nsv_parse_NSVf_header(s, ap);
530 /* we need the first NSVs also... */
531 if (nsv->state == NSV_FOUND_NSVS) {
532 err = nsv_parse_NSVs_header(s, ap);
533 break; /* we just want the first one */
536 if (s->nb_streams < 1) /* no luck so far */
538 /* now read the first chunk, so we can attempt to decode more info */
539 err = nsv_read_chunk(s, 1);
541 av_dlog(s, "parsed header\n");
545 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
547 NSVContext *nsv = s->priv_data;
548 AVIOContext *pb = s->pb;
549 AVStream *st[2] = {NULL, NULL};
553 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
557 uint32_t av_unused auxtag;
559 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
561 if (nsv->ahead[0].data || nsv->ahead[1].data)
562 return 0; //-1; /* hey! eat what you've in your plate first! */
568 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
572 if (nsv->state == NSV_FOUND_NSVS)
573 err = nsv_parse_NSVs_header(s, NULL);
576 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
579 auxcount = avio_r8(pb);
580 vsize = avio_rl16(pb);
581 asize = avio_rl16(pb);
582 vsize = (vsize << 4) | (auxcount >> 4);
584 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
586 for (i = 0; i < auxcount; i++) {
587 auxsize = avio_rl16(pb);
588 auxtag = avio_rl32(pb);
589 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
591 ((auxtag >> 8) & 0x0ff),
592 ((auxtag >> 16) & 0x0ff),
593 ((auxtag >> 24) & 0x0ff),
595 avio_skip(pb, auxsize);
596 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
601 if (!vsize && !asize) {
602 nsv->state = NSV_UNSYNC;
603 goto null_chunk_retry;
606 /* map back streams to v,a */
608 st[s->streams[0]->id] = s->streams[0];
610 st[s->streams[1]->id] = s->streams[1];
612 if (vsize/* && st[NSV_ST_VIDEO]*/) {
613 nst = st[NSV_ST_VIDEO]->priv_data;
614 pkt = &nsv->ahead[NSV_ST_VIDEO];
615 av_get_packet(pb, pkt, vsize);
616 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
617 pkt->dts = nst->frame_offset;
618 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
619 for (i = 0; i < FFMIN(8, vsize); i++)
620 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
623 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
625 if (asize/*st[NSV_ST_AUDIO]*/) {
626 nst = st[NSV_ST_AUDIO]->priv_data;
627 pkt = &nsv->ahead[NSV_ST_AUDIO];
628 /* read raw audio specific header on the first audio chunk... */
629 /* on ALL audio chunks ?? seems so! */
630 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
635 channels = avio_r8(pb);
636 samplerate = avio_rl16(pb);
638 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
640 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
642 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
644 bps /= channels; // ???
646 st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
647 samplerate /= 4;/* UGH ??? XXX */
649 st[NSV_ST_AUDIO]->codec->channels = channels;
650 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
651 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
654 av_get_packet(pb, pkt, asize);
655 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
656 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
657 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
658 /* on a nsvs frame we have new information on a/v sync */
659 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
660 pkt->dts *= (int64_t)1000 * nsv->framerate.den;
661 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
662 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
667 nsv->state = NSV_UNSYNC;
672 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
674 NSVContext *nsv = s->priv_data;
677 av_dlog(s, "%s()\n", __FUNCTION__);
679 /* in case we don't already have something to eat ... */
680 if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
681 err = nsv_read_chunk(s, 0);
685 /* now pick one of the plates */
686 for (i = 0; i < 2; i++) {
687 if (nsv->ahead[i].data) {
688 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
689 /* avoid the cost of new_packet + memcpy(->data) */
690 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
691 nsv->ahead[i].data = NULL; /* we ate that one */
696 /* this restaurant is not approvisionned :^] */
700 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
702 NSVContext *nsv = s->priv_data;
703 AVStream *st = s->streams[stream_index];
704 NSVStream *nst = st->priv_data;
707 index = av_index_search_timestamp(st, timestamp, flags);
711 avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
712 nst->frame_offset = st->index_entries[index].timestamp;
713 nsv->state = NSV_UNSYNC;
717 static int nsv_read_close(AVFormatContext *s)
720 NSVContext *nsv = s->priv_data;
722 av_freep(&nsv->nsvs_file_offset);
723 av_freep(&nsv->nsvs_timestamps);
724 if (nsv->ahead[0].data)
725 av_free_packet(&nsv->ahead[0]);
726 if (nsv->ahead[1].data)
727 av_free_packet(&nsv->ahead[1]);
731 for(i=0;i<s->nb_streams;i++) {
732 AVStream *st = s->streams[i];
733 NSVStream *ast = st->priv_data;
735 av_free(ast->index_entries);
738 av_free(st->codec->palctrl);
745 static int nsv_probe(AVProbeData *p)
749 int vsize, asize, auxcount;
751 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
752 /* check file header */
753 /* streamed files might not have any header */
754 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
755 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
756 return AVPROBE_SCORE_MAX;
757 /* XXX: do streamed files always start at chunk boundary ?? */
758 /* or do we need to search NSVs in the byte stream ? */
759 /* seems the servers don't bother starting clean chunks... */
760 /* sometimes even the first header is at 9KB or something :^) */
761 for (i = 1; i < p->buf_size - 3; i++) {
762 if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
763 p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
764 score = AVPROBE_SCORE_MAX/5;
765 /* Get the chunk size and check if at the end we are getting 0xBEEF */
766 auxcount = p->buf[i+19];
767 vsize = p->buf[i+20] | p->buf[i+21] << 8;
768 asize = p->buf[i+22] | p->buf[i+23] << 8;
769 vsize = (vsize << 4) | (auxcount >> 4);
770 if ((asize + vsize + i + 23) < p->buf_size - 2) {
771 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
772 p->buf[i+23+asize+vsize+2] == 0xBE)
773 return AVPROBE_SCORE_MAX-20;
777 /* so we'll have more luck on extension... */
778 if (av_match_ext(p->filename, "nsv"))
779 return AVPROBE_SCORE_MAX/2;
780 /* FIXME: add mime-type check */
784 AVInputFormat ff_nsv_demuxer = {
786 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
787 .priv_data_size = sizeof(NSVContext),
788 .read_probe = nsv_probe,
789 .read_header = nsv_read_header,
790 .read_packet = nsv_read_packet,
791 .read_close = nsv_read_close,
792 .read_seek = nsv_read_seek,