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)
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((size_t)strings_size + 1);
319 return AVERROR(ENOMEM);
320 endp = strings + strings_size;
321 avio_read(pb, strings, strings_size);
324 p++; /* strip out spaces */
329 if (!p || p >= endp-2)
334 p = strchr(p, quote);
338 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
339 av_dict_set(&s->metadata, token, value, 0);
346 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
348 if (table_entries_used > 0) {
350 nsv->index_entries = table_entries_used;
351 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
353 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
354 if (!nsv->nsvs_file_offset)
355 return AVERROR(ENOMEM);
357 for(i=0;i<table_entries_used;i++)
358 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
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);
371 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
373 #ifdef DEBUG_DUMP_INDEX
374 #define V(v) ((v<0x20 || v > 127)?'.':v)
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++) {
380 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
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]) );
388 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
392 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
396 nsv->state = NSV_HAS_READ_NSVF;
400 static int nsv_parse_NSVs_header(AVFormatContext *s)
402 NSVContext *nsv = s->priv_data;
403 AVIOContext *pb = s->pb;
405 uint16_t vwidth, vheight;
406 AVRational framerate;
410 av_dlog(s, "%s()\n", __FUNCTION__);
412 vtag = avio_rl32(pb);
413 atag = avio_rl32(pb);
414 vwidth = avio_rl16(pb);
415 vheight = avio_rl16(pb);
418 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
419 if(i&0x80) { /* odd way of giving native framerates from docs */
421 if(t<16) framerate = (AVRational){1, t+1};
422 else framerate = (AVRational){t-15, 1};
425 framerate.num *= 1000;
426 framerate.den *= 1001;
429 if((i&3)==3) framerate.num *= 24;
430 else if((i&3)==2) framerate.num *= 25;
431 else framerate.num *= 30;
434 framerate= (AVRational){i, 1};
436 nsv->avsync = avio_rl16(pb);
437 nsv->framerate = framerate;
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);
443 /* XXX change to ap != NULL ? */
444 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
447 nsv->vwidth = vwidth;
448 nsv->vheight = vwidth;
449 if (vtag != T_NONE) {
451 st = avformat_new_stream(s, NULL);
455 st->id = NSV_ST_VIDEO;
456 nst = av_mallocz(sizeof(NSVStream));
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 */
467 avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
469 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
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);
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);
481 if (atag != T_NONE) {
482 #ifndef DISABLE_AUDIO
483 st = avformat_new_stream(s, NULL);
487 st->id = NSV_ST_AUDIO;
488 nst = av_mallocz(sizeof(NSVStream));
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);
496 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
498 /* set timebase to common denominator of ms and framerate */
499 avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
501 st->duration = (int64_t)nsv->duration * framerate.num;
504 #ifdef CHECK_SUBSEQUENT_NSVS
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");
510 #endif /* CHECK_SUBSEQUENT_NSVS */
513 nsv->state = NSV_HAS_READ_NSVS;
517 nsv->state = NSV_UNSYNC;
521 static int nsv_read_header(AVFormatContext *s)
523 NSVContext *nsv = s->priv_data;
526 av_dlog(s, "%s()\n", __FUNCTION__);
527 av_dlog(s, "filename '%s'\n", s->filename);
529 nsv->state = NSV_UNSYNC;
530 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
532 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
533 if (nsv_resync(s) < 0)
535 if (nsv->state == NSV_FOUND_NSVF) {
536 err = nsv_parse_NSVf_header(s);
540 /* we need the first NSVs also... */
541 if (nsv->state == NSV_FOUND_NSVS) {
542 err = nsv_parse_NSVs_header(s);
545 break; /* we just want the first one */
548 if (s->nb_streams < 1) /* no luck so far */
550 /* now read the first chunk, so we can attempt to decode more info */
551 err = nsv_read_chunk(s, 1);
553 av_dlog(s, "parsed header\n");
557 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
559 NSVContext *nsv = s->priv_data;
560 AVIOContext *pb = s->pb;
561 AVStream *st[2] = {NULL, NULL};
565 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
569 uint32_t av_unused auxtag;
571 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
573 if (nsv->ahead[0].data || nsv->ahead[1].data)
574 return 0; //-1; /* hey! eat what you've in your plate first! */
580 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
584 if (nsv->state == NSV_FOUND_NSVS)
585 err = nsv_parse_NSVs_header(s);
588 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
591 auxcount = avio_r8(pb);
592 vsize = avio_rl16(pb);
593 asize = avio_rl16(pb);
594 vsize = (vsize << 4) | (auxcount >> 4);
596 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
598 for (i = 0; i < auxcount; i++) {
599 auxsize = avio_rl16(pb);
600 auxtag = avio_rl32(pb);
601 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
603 ((auxtag >> 8) & 0x0ff),
604 ((auxtag >> 16) & 0x0ff),
605 ((auxtag >> 24) & 0x0ff),
607 avio_skip(pb, auxsize);
608 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
613 if (!vsize && !asize) {
614 nsv->state = NSV_UNSYNC;
615 goto null_chunk_retry;
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];
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]);
635 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
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*/) {
647 channels = avio_r8(pb);
648 samplerate = avio_rl16(pb);
650 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
652 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
654 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
656 bps /= channels; // ???
658 st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
659 samplerate /= 4;/* UGH ??? XXX */
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);
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);
679 nsv->state = NSV_UNSYNC;
684 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
686 NSVContext *nsv = s->priv_data;
689 av_dlog(s, "%s()\n", __FUNCTION__);
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);
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 */
708 /* this restaurant is not approvisionned :^] */
712 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
714 NSVContext *nsv = s->priv_data;
715 AVStream *st = s->streams[stream_index];
716 NSVStream *nst = st->priv_data;
719 index = av_index_search_timestamp(st, timestamp, flags);
723 avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
724 nst->frame_offset = st->index_entries[index].timestamp;
725 nsv->state = NSV_UNSYNC;
729 static int nsv_read_close(AVFormatContext *s)
732 NSVContext *nsv = s->priv_data;
734 av_freep(&nsv->nsvs_file_offset);
735 av_freep(&nsv->nsvs_timestamps);
736 if (nsv->ahead[0].data)
737 av_free_packet(&nsv->ahead[0]);
738 if (nsv->ahead[1].data)
739 av_free_packet(&nsv->ahead[1]);
743 for(i=0;i<s->nb_streams;i++) {
744 AVStream *st = s->streams[i];
745 NSVStream *ast = st->priv_data;
747 av_free(ast->index_entries);
750 av_free(st->codec->palctrl);
757 static int nsv_probe(AVProbeData *p)
761 int vsize, asize, auxcount;
763 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
764 /* check file header */
765 /* streamed files might not have any header */
766 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
767 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
768 return AVPROBE_SCORE_MAX;
769 /* XXX: do streamed files always start at chunk boundary ?? */
770 /* or do we need to search NSVs in the byte stream ? */
771 /* seems the servers don't bother starting clean chunks... */
772 /* sometimes even the first header is at 9KB or something :^) */
773 for (i = 1; i < p->buf_size - 3; i++) {
774 if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
775 p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
776 score = AVPROBE_SCORE_MAX/5;
777 /* Get the chunk size and check if at the end we are getting 0xBEEF */
778 auxcount = p->buf[i+19];
779 vsize = p->buf[i+20] | p->buf[i+21] << 8;
780 asize = p->buf[i+22] | p->buf[i+23] << 8;
781 vsize = (vsize << 4) | (auxcount >> 4);
782 if ((asize + vsize + i + 23) < p->buf_size - 2) {
783 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
784 p->buf[i+23+asize+vsize+2] == 0xBE)
785 return AVPROBE_SCORE_MAX-20;
789 /* so we'll have more luck on extension... */
790 if (av_match_ext(p->filename, "nsv"))
791 return AVPROBE_SCORE_MAX/2;
792 /* FIXME: add mime-type check */
796 AVInputFormat ff_nsv_demuxer = {
798 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
799 .priv_data_size = sizeof(NSVContext),
800 .read_probe = nsv_probe,
801 .read_header = nsv_read_header,
802 .read_packet = nsv_read_packet,
803 .read_close = nsv_read_close,
804 .read_seek = nsv_read_seek,