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"
26 #include "libavutil/dict.h"
28 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
29 #define CHECK_SUBSEQUENT_NSVS
30 //#define DISABLE_AUDIO
32 /* max bytes to crawl for trying to resync
33 * stupid streaming servers don't start at chunk boundaries...
35 #define NSV_MAX_RESYNC (500*1024)
36 #define NSV_MAX_RESYNC_TRIES 300
39 * First version by Francois Revol - revol@free.fr
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/
46 * (3) http://ultravox.aol.com/NSVFormat.rtf
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
54 * notes on the header (Francois Revol):
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.
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.
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.
71 * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
72 * so the header seems to not be mandatory. (for streaming).
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))"
84 * - handle timestamps !!!
86 * - mime-type in probe()
92 uint32_t chunk_tag; /* 'NSVf' */
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 */
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 */
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;
117 struct nsv_pcm_header {
118 uint8_t bits_per_sample;
119 uint8_t channel_count;
120 uint16_t sample_rate;
124 /* variation from avi.h */
125 /*typedef struct CodecTag {
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) */
140 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
141 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
143 /* hardcoded stream indexes */
144 #define NSV_ST_VIDEO 0
145 #define NSV_ST_AUDIO 1
146 #define NSV_ST_SUBT 2
159 typedef struct NSVStream {
160 int frame_offset; /* current frame (video) or byte (audio) counter
161 (used to compute the pts) */
164 int sample_size; /* audio only data */
167 int new_frame_offset; /* temporary storage (used during seek) */
168 int cum_len; /* temporary storage (used during seek) */
174 uint32_t *nsvs_file_offset;
176 enum NSVStatus state;
177 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
181 uint16_t vwidth, vheight;
183 AVRational framerate;
184 uint32_t *nsvs_timestamps;
185 //DVDemuxContext* dv_demux;
188 static const AVCodecTag nsv_codec_video_tags[] = {
189 { CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
190 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
191 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
192 { CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
193 { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
194 { CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
195 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
196 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
197 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
199 { CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
200 { CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
202 { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
203 { CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
204 { CODEC_ID_NONE, 0 },
207 static const AVCodecTag nsv_codec_audio_tags[] = {
208 { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
209 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
210 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
211 { CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
212 { CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
213 { CODEC_ID_NONE, 0 },
216 //static int nsv_load_index(AVFormatContext *s);
217 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
219 #define print_tag(str, tag, size) \
220 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
223 (tag >> 16) & 0xff, \
226 /* try to find something we recognize, and set the state accordingly */
227 static int nsv_resync(AVFormatContext *s)
229 NSVContext *nsv = s->priv_data;
230 AVIOContext *pb = s->pb;
234 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
236 //nsv->state = NSV_UNSYNC;
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;
247 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
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;
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;
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;
268 av_dlog(s, "NSV sync lost\n");
272 static int nsv_parse_NSVf_header(AVFormatContext *s, AVFormatParameters *ap)
274 NSVContext *nsv = s->priv_data;
275 AVIOContext *pb = s->pb;
276 unsigned int av_unused file_size;
281 int table_entries_used;
283 av_dlog(s, "%s()\n", __FUNCTION__);
285 nsv->state = NSV_UNSYNC; /* in case we fail */
287 size = avio_rl32(pb);
290 nsv->NSVf_end = size;
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);
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
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);
309 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
311 if (strings_size > 0) {
312 char *strings; /* last byte will be '\0' to play safe with str*() */
317 p = strings = av_mallocz(strings_size + 1);
318 endp = strings + strings_size;
319 avio_read(pb, strings, strings_size);
322 p++; /* strip out spaces */
327 if (!p || p >= endp-2)
332 p = strchr(p, quote);
336 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
337 av_dict_set(&s->metadata, token, value, 0);
344 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
346 if (table_entries_used > 0) {
348 nsv->index_entries = table_entries_used;
349 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
351 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
353 for(i=0;i<table_entries_used;i++)
354 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
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 for(i=0;i<table_entries_used;i++) {
360 nsv->nsvs_timestamps[i] = avio_rl32(pb);
365 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
367 #ifdef DEBUG_DUMP_INDEX
368 #define V(v) ((v<0x20 || v > 127)?'.':v)
370 av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
371 av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
372 for (i = 0; i < table_entries; i++) {
374 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
376 av_dlog(s, "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->nsvs_file_offset[i], size + nsv->nsvs_file_offset[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]) );
382 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
386 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
390 nsv->state = NSV_HAS_READ_NSVF;
394 static int nsv_parse_NSVs_header(AVFormatContext *s, AVFormatParameters *ap)
396 NSVContext *nsv = s->priv_data;
397 AVIOContext *pb = s->pb;
399 uint16_t vwidth, vheight;
400 AVRational framerate;
404 av_dlog(s, "%s()\n", __FUNCTION__);
406 vtag = avio_rl32(pb);
407 atag = avio_rl32(pb);
408 vwidth = avio_rl16(pb);
409 vheight = avio_rl16(pb);
412 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
413 if(i&0x80) { /* odd way of giving native framerates from docs */
415 if(t<16) framerate = (AVRational){1, t+1};
416 else framerate = (AVRational){t-15, 1};
419 framerate.num *= 1000;
420 framerate.den *= 1001;
423 if((i&3)==3) framerate.num *= 24;
424 else if((i&3)==2) framerate.num *= 25;
425 else framerate.num *= 30;
428 framerate= (AVRational){i, 1};
430 nsv->avsync = avio_rl16(pb);
431 nsv->framerate = framerate;
433 print_tag("NSV NSVs vtag", vtag, 0);
434 print_tag("NSV NSVs atag", atag, 0);
435 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
437 /* XXX change to ap != NULL ? */
438 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
441 nsv->vwidth = vwidth;
442 nsv->vheight = vwidth;
443 if (vtag != T_NONE) {
445 st = avformat_new_stream(s, NULL);
449 st->id = NSV_ST_VIDEO;
450 nst = av_mallocz(sizeof(NSVStream));
454 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
455 st->codec->codec_tag = vtag;
456 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
457 st->codec->width = vwidth;
458 st->codec->height = vheight;
459 st->codec->bits_per_coded_sample = 24; /* depth XXX */
461 avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
463 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
465 for(i=0;i<nsv->index_entries;i++) {
466 if(nsv->nsvs_timestamps) {
467 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
468 0, 0, AVINDEX_KEYFRAME);
470 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
471 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
475 if (atag != T_NONE) {
476 #ifndef DISABLE_AUDIO
477 st = avformat_new_stream(s, NULL);
481 st->id = NSV_ST_AUDIO;
482 nst = av_mallocz(sizeof(NSVStream));
486 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
487 st->codec->codec_tag = atag;
488 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
490 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
492 /* set timebase to common denominator of ms and framerate */
493 avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
495 st->duration = (int64_t)nsv->duration * framerate.num;
498 #ifdef CHECK_SUBSEQUENT_NSVS
500 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
501 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
504 #endif /* CHECK_SUBSEQUENT_NSVS */
507 nsv->state = NSV_HAS_READ_NSVS;
511 nsv->state = NSV_UNSYNC;
515 static int nsv_read_header(AVFormatContext *s, AVFormatParameters *ap)
517 NSVContext *nsv = s->priv_data;
520 av_dlog(s, "%s()\n", __FUNCTION__);
521 av_dlog(s, "filename '%s'\n", s->filename);
523 nsv->state = NSV_UNSYNC;
524 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
526 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
527 if (nsv_resync(s) < 0)
529 if (nsv->state == NSV_FOUND_NSVF)
530 err = nsv_parse_NSVf_header(s, ap);
531 /* we need the first NSVs also... */
532 if (nsv->state == NSV_FOUND_NSVS) {
533 err = nsv_parse_NSVs_header(s, ap);
534 break; /* we just want the first one */
537 if (s->nb_streams < 1) /* no luck so far */
539 /* now read the first chunk, so we can attempt to decode more info */
540 err = nsv_read_chunk(s, 1);
542 av_dlog(s, "parsed header\n");
546 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
548 NSVContext *nsv = s->priv_data;
549 AVIOContext *pb = s->pb;
550 AVStream *st[2] = {NULL, NULL};
554 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
558 uint32_t av_unused auxtag;
560 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
562 if (nsv->ahead[0].data || nsv->ahead[1].data)
563 return 0; //-1; /* hey! eat what you've in your plate first! */
569 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
573 if (nsv->state == NSV_FOUND_NSVS)
574 err = nsv_parse_NSVs_header(s, NULL);
577 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
580 auxcount = avio_r8(pb);
581 vsize = avio_rl16(pb);
582 asize = avio_rl16(pb);
583 vsize = (vsize << 4) | (auxcount >> 4);
585 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
587 for (i = 0; i < auxcount; i++) {
588 auxsize = avio_rl16(pb);
589 auxtag = avio_rl32(pb);
590 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
592 ((auxtag >> 8) & 0x0ff),
593 ((auxtag >> 16) & 0x0ff),
594 ((auxtag >> 24) & 0x0ff),
596 avio_skip(pb, auxsize);
597 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
602 if (!vsize && !asize) {
603 nsv->state = NSV_UNSYNC;
604 goto null_chunk_retry;
607 /* map back streams to v,a */
609 st[s->streams[0]->id] = s->streams[0];
611 st[s->streams[1]->id] = s->streams[1];
613 if (vsize/* && st[NSV_ST_VIDEO]*/) {
614 nst = st[NSV_ST_VIDEO]->priv_data;
615 pkt = &nsv->ahead[NSV_ST_VIDEO];
616 av_get_packet(pb, pkt, vsize);
617 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
618 pkt->dts = nst->frame_offset;
619 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
620 for (i = 0; i < FFMIN(8, vsize); i++)
621 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
624 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
626 if (asize/*st[NSV_ST_AUDIO]*/) {
627 nst = st[NSV_ST_AUDIO]->priv_data;
628 pkt = &nsv->ahead[NSV_ST_AUDIO];
629 /* read raw audio specific header on the first audio chunk... */
630 /* on ALL audio chunks ?? seems so! */
631 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
636 channels = avio_r8(pb);
637 samplerate = avio_rl16(pb);
639 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
641 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
643 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
645 bps /= channels; // ???
647 st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
648 samplerate /= 4;/* UGH ??? XXX */
650 st[NSV_ST_AUDIO]->codec->channels = channels;
651 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
652 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
655 av_get_packet(pb, pkt, asize);
656 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
657 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
658 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
659 /* on a nsvs frame we have new information on a/v sync */
660 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
661 pkt->dts *= (int64_t)1000 * nsv->framerate.den;
662 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
663 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
668 nsv->state = NSV_UNSYNC;
673 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
675 NSVContext *nsv = s->priv_data;
678 av_dlog(s, "%s()\n", __FUNCTION__);
680 /* in case we don't already have something to eat ... */
681 if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
682 err = nsv_read_chunk(s, 0);
686 /* now pick one of the plates */
687 for (i = 0; i < 2; i++) {
688 if (nsv->ahead[i].data) {
689 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
690 /* avoid the cost of new_packet + memcpy(->data) */
691 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
692 nsv->ahead[i].data = NULL; /* we ate that one */
697 /* this restaurant is not approvisionned :^] */
701 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
703 NSVContext *nsv = s->priv_data;
704 AVStream *st = s->streams[stream_index];
705 NSVStream *nst = st->priv_data;
708 index = av_index_search_timestamp(st, timestamp, flags);
712 avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
713 nst->frame_offset = st->index_entries[index].timestamp;
714 nsv->state = NSV_UNSYNC;
718 static int nsv_read_close(AVFormatContext *s)
721 NSVContext *nsv = s->priv_data;
723 av_freep(&nsv->nsvs_file_offset);
724 av_freep(&nsv->nsvs_timestamps);
725 if (nsv->ahead[0].data)
726 av_free_packet(&nsv->ahead[0]);
727 if (nsv->ahead[1].data)
728 av_free_packet(&nsv->ahead[1]);
732 for(i=0;i<s->nb_streams;i++) {
733 AVStream *st = s->streams[i];
734 NSVStream *ast = st->priv_data;
736 av_free(ast->index_entries);
739 av_free(st->codec->palctrl);
746 static int nsv_probe(AVProbeData *p)
750 int vsize, asize, auxcount;
752 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
753 /* check file header */
754 /* streamed files might not have any header */
755 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
756 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
757 return AVPROBE_SCORE_MAX;
758 /* XXX: do streamed files always start at chunk boundary ?? */
759 /* or do we need to search NSVs in the byte stream ? */
760 /* seems the servers don't bother starting clean chunks... */
761 /* sometimes even the first header is at 9KB or something :^) */
762 for (i = 1; i < p->buf_size - 3; i++) {
763 if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
764 p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
765 score = AVPROBE_SCORE_MAX/5;
766 /* Get the chunk size and check if at the end we are getting 0xBEEF */
767 auxcount = p->buf[i+19];
768 vsize = p->buf[i+20] | p->buf[i+21] << 8;
769 asize = p->buf[i+22] | p->buf[i+23] << 8;
770 vsize = (vsize << 4) | (auxcount >> 4);
771 if ((asize + vsize + i + 23) < p->buf_size - 2) {
772 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
773 p->buf[i+23+asize+vsize+2] == 0xBE)
774 return AVPROBE_SCORE_MAX-20;
778 /* so we'll have more luck on extension... */
779 if (av_match_ext(p->filename, "nsv"))
780 return AVPROBE_SCORE_MAX/2;
781 /* FIXME: add mime-type check */
785 AVInputFormat ff_nsv_demuxer = {
787 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
788 .priv_data_size = sizeof(NSVContext),
789 .read_probe = nsv_probe,
790 .read_header = nsv_read_header,
791 .read_packet = nsv_read_packet,
792 .read_close = nsv_read_close,
793 .read_seek = nsv_read_seek,