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 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
79 * - handle timestamps !!!
81 * - mime-type in probe()
87 uint32_t chunk_tag; /* 'NSVf' */
89 uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
90 uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
91 uint32_t info_strings_size; /* size of the info strings */ //unknown2;
92 uint32_t table_entries;
93 uint32_t table_entries_used; /* the left ones should be -1 */
97 uint32_t chunk_tag; /* 'NSVs' */
98 uint32_t v4cc; /* or 'NONE' */
99 uint32_t a4cc; /* or 'NONE' */
100 uint16_t vwidth; /* assert(vwidth%16==0) */
101 uint16_t vheight; /* assert(vheight%16==0) */
102 uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
106 struct nsv_avchunk_header {
107 uint8_t vchunk_size_lsb;
108 uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
109 uint16_t achunk_size;
112 struct nsv_pcm_header {
113 uint8_t bits_per_sample;
114 uint8_t channel_count;
115 uint16_t sample_rate;
119 /* variation from avi.h */
120 /*typedef struct CodecTag {
127 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
128 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
129 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
130 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
131 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
132 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
133 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
135 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
136 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
138 /* hardcoded stream indexes */
139 #define NSV_ST_VIDEO 0
140 #define NSV_ST_AUDIO 1
141 #define NSV_ST_SUBT 2
154 typedef struct NSVStream {
155 int frame_offset; /* current frame (video) or byte (audio) counter
156 (used to compute the pts) */
159 int sample_size; /* audio only data */
162 int new_frame_offset; /* temporary storage (used during seek) */
163 int cum_len; /* temporary storage (used during seek) */
169 uint32_t *nsvs_file_offset;
171 enum NSVStatus state;
172 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
176 uint16_t vwidth, vheight;
178 AVRational framerate;
179 uint32_t *nsvs_timestamps;
180 //DVDemuxContext* dv_demux;
183 static const AVCodecTag nsv_codec_video_tags[] = {
184 { CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
185 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
186 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
187 { CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
188 { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
189 { CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
190 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
191 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
192 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
194 { CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
195 { CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
197 { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
198 { CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
199 { CODEC_ID_NONE, 0 },
202 static const AVCodecTag nsv_codec_audio_tags[] = {
203 { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
204 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
205 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
206 { CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
207 { CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
208 { CODEC_ID_NONE, 0 },
211 //static int nsv_load_index(AVFormatContext *s);
212 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
214 #define print_tag(str, tag, size) \
215 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
218 (tag >> 16) & 0xff, \
221 /* try to find something we recognize, and set the state accordingly */
222 static int nsv_resync(AVFormatContext *s)
224 NSVContext *nsv = s->priv_data;
225 AVIOContext *pb = s->pb;
229 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
231 //nsv->state = NSV_UNSYNC;
233 for (i = 0; i < NSV_MAX_RESYNC; i++) {
234 if (pb->eof_reached) {
235 av_dlog(s, "NSV EOF\n");
236 nsv->state = NSV_UNSYNC;
242 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
245 if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
246 av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
247 nsv->state = NSV_FOUND_BEEF;
250 /* we read as big endian, thus the MK*BE* */
251 if (v == TB_NSVF) { /* NSVf */
252 av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
253 nsv->state = NSV_FOUND_NSVF;
256 if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
257 av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
258 nsv->state = NSV_FOUND_NSVS;
263 av_dlog(s, "NSV sync lost\n");
267 static int nsv_parse_NSVf_header(AVFormatContext *s, AVFormatParameters *ap)
269 NSVContext *nsv = s->priv_data;
270 AVIOContext *pb = s->pb;
271 unsigned int av_unused file_size;
276 int table_entries_used;
278 av_dlog(s, "%s()\n", __FUNCTION__);
280 nsv->state = NSV_UNSYNC; /* in case we fail */
282 size = avio_rl32(pb);
285 nsv->NSVf_end = size;
287 //s->file_size = (uint32_t)avio_rl32(pb);
288 file_size = (uint32_t)avio_rl32(pb);
289 av_dlog(s, "NSV NSVf chunk_size %u\n", size);
290 av_dlog(s, "NSV NSVf file_size %u\n", file_size);
292 nsv->duration = duration = avio_rl32(pb); /* in ms */
293 av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
294 // XXX: store it in AVStreams
296 strings_size = avio_rl32(pb);
297 table_entries = avio_rl32(pb);
298 table_entries_used = avio_rl32(pb);
299 av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
300 strings_size, table_entries, table_entries_used);
304 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
306 if (strings_size > 0) {
307 char *strings; /* last byte will be '\0' to play safe with str*() */
312 p = strings = av_mallocz(strings_size + 1);
313 endp = strings + strings_size;
314 avio_read(pb, strings, strings_size);
317 p++; /* strip out spaces */
322 if (!p || p >= endp-2)
327 p = strchr(p, quote);
331 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
332 av_dict_set(&s->metadata, token, value, 0);
339 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
341 if (table_entries_used > 0) {
343 nsv->index_entries = table_entries_used;
344 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
346 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
348 for(i=0;i<table_entries_used;i++)
349 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
351 if(table_entries > table_entries_used &&
352 avio_rl32(pb) == MKTAG('T','O','C','2')) {
353 nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
354 for(i=0;i<table_entries_used;i++) {
355 nsv->nsvs_timestamps[i] = avio_rl32(pb);
360 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
362 #ifdef DEBUG_DUMP_INDEX
363 #define V(v) ((v<0x20 || v > 127)?'.':v)
365 av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
366 av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
367 for (i = 0; i < table_entries; i++) {
369 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
371 av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
372 "%c%c%c%c%c%c%c%c\n",
373 nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
374 b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
375 V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
377 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
381 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
385 nsv->state = NSV_HAS_READ_NSVF;
389 static int nsv_parse_NSVs_header(AVFormatContext *s, AVFormatParameters *ap)
391 NSVContext *nsv = s->priv_data;
392 AVIOContext *pb = s->pb;
394 uint16_t vwidth, vheight;
395 AVRational framerate;
399 av_dlog(s, "%s()\n", __FUNCTION__);
401 vtag = avio_rl32(pb);
402 atag = avio_rl32(pb);
403 vwidth = avio_rl16(pb);
404 vheight = avio_rl16(pb);
407 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
408 if(i&0x80) { /* odd way of giving native framerates from docs */
410 if(t<16) framerate = (AVRational){1, t+1};
411 else framerate = (AVRational){t-15, 1};
414 framerate.num *= 1000;
415 framerate.den *= 1001;
418 if((i&3)==3) framerate.num *= 24;
419 else if((i&3)==2) framerate.num *= 25;
420 else framerate.num *= 30;
423 framerate= (AVRational){i, 1};
425 nsv->avsync = avio_rl16(pb);
426 nsv->framerate = framerate;
428 print_tag("NSV NSVs vtag", vtag, 0);
429 print_tag("NSV NSVs atag", atag, 0);
430 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
432 /* XXX change to ap != NULL ? */
433 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
436 nsv->vwidth = vwidth;
437 nsv->vheight = vwidth;
438 if (vtag != T_NONE) {
440 st = av_new_stream(s, NSV_ST_VIDEO);
444 nst = av_mallocz(sizeof(NSVStream));
448 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
449 st->codec->codec_tag = vtag;
450 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
451 st->codec->width = vwidth;
452 st->codec->height = vheight;
453 st->codec->bits_per_coded_sample = 24; /* depth XXX */
455 av_set_pts_info(st, 64, framerate.den, framerate.num);
457 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
459 for(i=0;i<nsv->index_entries;i++) {
460 if(nsv->nsvs_timestamps) {
461 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
462 0, 0, AVINDEX_KEYFRAME);
464 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
465 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
469 if (atag != T_NONE) {
470 #ifndef DISABLE_AUDIO
471 st = av_new_stream(s, NSV_ST_AUDIO);
475 nst = av_mallocz(sizeof(NSVStream));
479 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
480 st->codec->codec_tag = atag;
481 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
483 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
485 /* set timebase to common denominator of ms and framerate */
486 av_set_pts_info(st, 64, 1, framerate.num*1000);
488 st->duration = (int64_t)nsv->duration * framerate.num;
491 #ifdef CHECK_SUBSEQUENT_NSVS
493 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
494 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
497 #endif /* CHECK_SUBSEQUENT_NSVS */
500 nsv->state = NSV_HAS_READ_NSVS;
504 nsv->state = NSV_UNSYNC;
508 static int nsv_read_header(AVFormatContext *s, AVFormatParameters *ap)
510 NSVContext *nsv = s->priv_data;
513 av_dlog(s, "%s()\n", __FUNCTION__);
514 av_dlog(s, "filename '%s'\n", s->filename);
516 nsv->state = NSV_UNSYNC;
517 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
519 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
520 if (nsv_resync(s) < 0)
522 if (nsv->state == NSV_FOUND_NSVF)
523 err = nsv_parse_NSVf_header(s, ap);
524 /* we need the first NSVs also... */
525 if (nsv->state == NSV_FOUND_NSVS) {
526 err = nsv_parse_NSVs_header(s, ap);
527 break; /* we just want the first one */
530 if (s->nb_streams < 1) /* no luck so far */
532 /* now read the first chunk, so we can attempt to decode more info */
533 err = nsv_read_chunk(s, 1);
535 av_dlog(s, "parsed header\n");
539 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
541 NSVContext *nsv = s->priv_data;
542 AVIOContext *pb = s->pb;
543 AVStream *st[2] = {NULL, NULL};
547 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
551 uint32_t av_unused auxtag;
553 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
555 if (nsv->ahead[0].data || nsv->ahead[1].data)
556 return 0; //-1; /* hey! eat what you've in your plate first! */
562 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
566 if (nsv->state == NSV_FOUND_NSVS)
567 err = nsv_parse_NSVs_header(s, NULL);
570 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
573 auxcount = avio_r8(pb);
574 vsize = avio_rl16(pb);
575 asize = avio_rl16(pb);
576 vsize = (vsize << 4) | (auxcount >> 4);
578 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
580 for (i = 0; i < auxcount; i++) {
581 auxsize = avio_rl16(pb);
582 auxtag = avio_rl32(pb);
583 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
585 ((auxtag >> 8) & 0x0ff),
586 ((auxtag >> 16) & 0x0ff),
587 ((auxtag >> 24) & 0x0ff),
589 avio_skip(pb, auxsize);
590 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
595 if (!vsize && !asize) {
596 nsv->state = NSV_UNSYNC;
597 goto null_chunk_retry;
600 /* map back streams to v,a */
602 st[s->streams[0]->id] = s->streams[0];
604 st[s->streams[1]->id] = s->streams[1];
606 if (vsize/* && st[NSV_ST_VIDEO]*/) {
607 nst = st[NSV_ST_VIDEO]->priv_data;
608 pkt = &nsv->ahead[NSV_ST_VIDEO];
609 av_get_packet(pb, pkt, vsize);
610 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
611 pkt->dts = nst->frame_offset;
612 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
613 for (i = 0; i < FFMIN(8, vsize); i++)
614 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
617 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
619 if (asize/*st[NSV_ST_AUDIO]*/) {
620 nst = st[NSV_ST_AUDIO]->priv_data;
621 pkt = &nsv->ahead[NSV_ST_AUDIO];
622 /* read raw audio specific header on the first audio chunk... */
623 /* on ALL audio chunks ?? seems so! */
624 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
629 channels = avio_r8(pb);
630 samplerate = avio_rl16(pb);
632 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
634 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
636 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
638 bps /= channels; // ???
640 st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
641 samplerate /= 4;/* UGH ??? XXX */
643 st[NSV_ST_AUDIO]->codec->channels = channels;
644 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
645 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
648 av_get_packet(pb, pkt, asize);
649 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
650 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
651 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
652 /* on a nsvs frame we have new information on a/v sync */
653 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
654 pkt->dts *= (int64_t)1000 * nsv->framerate.den;
655 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
656 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
661 nsv->state = NSV_UNSYNC;
666 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
668 NSVContext *nsv = s->priv_data;
671 av_dlog(s, "%s()\n", __FUNCTION__);
673 /* in case we don't already have something to eat ... */
674 if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
675 err = nsv_read_chunk(s, 0);
679 /* now pick one of the plates */
680 for (i = 0; i < 2; i++) {
681 if (nsv->ahead[i].data) {
682 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
683 /* avoid the cost of new_packet + memcpy(->data) */
684 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
685 nsv->ahead[i].data = NULL; /* we ate that one */
690 /* this restaurant is not approvisionned :^] */
694 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
696 NSVContext *nsv = s->priv_data;
697 AVStream *st = s->streams[stream_index];
698 NSVStream *nst = st->priv_data;
701 index = av_index_search_timestamp(st, timestamp, flags);
705 avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
706 nst->frame_offset = st->index_entries[index].timestamp;
707 nsv->state = NSV_UNSYNC;
711 static int nsv_read_close(AVFormatContext *s)
714 NSVContext *nsv = s->priv_data;
716 av_freep(&nsv->nsvs_file_offset);
717 av_freep(&nsv->nsvs_timestamps);
718 if (nsv->ahead[0].data)
719 av_free_packet(&nsv->ahead[0]);
720 if (nsv->ahead[1].data)
721 av_free_packet(&nsv->ahead[1]);
725 for(i=0;i<s->nb_streams;i++) {
726 AVStream *st = s->streams[i];
727 NSVStream *ast = st->priv_data;
729 av_free(ast->index_entries);
732 av_free(st->codec->palctrl);
739 static int nsv_probe(AVProbeData *p)
743 int vsize, asize, auxcount;
745 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
746 /* check file header */
747 /* streamed files might not have any header */
748 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
749 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
750 return AVPROBE_SCORE_MAX;
751 /* XXX: do streamed files always start at chunk boundary ?? */
752 /* or do we need to search NSVs in the byte stream ? */
753 /* seems the servers don't bother starting clean chunks... */
754 /* sometimes even the first header is at 9KB or something :^) */
755 for (i = 1; i < p->buf_size - 3; i++) {
756 if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
757 p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
758 score = AVPROBE_SCORE_MAX/5;
759 /* Get the chunk size and check if at the end we are getting 0xBEEF */
760 auxcount = p->buf[i+19];
761 vsize = p->buf[i+20] | p->buf[i+21] << 8;
762 asize = p->buf[i+22] | p->buf[i+23] << 8;
763 vsize = (vsize << 4) | (auxcount >> 4);
764 if ((asize + vsize + i + 23) < p->buf_size - 2) {
765 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
766 p->buf[i+23+asize+vsize+2] == 0xBE)
767 return AVPROBE_SCORE_MAX-20;
771 /* so we'll have more luck on extension... */
772 if (av_match_ext(p->filename, "nsv"))
773 return AVPROBE_SCORE_MAX/2;
774 /* FIXME: add mime-type check */
778 AVInputFormat ff_nsv_demuxer = {
780 NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),