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/attributes.h"
23 #include "libavutil/mathematics.h"
27 #include "libavutil/dict.h"
29 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
30 #define CHECK_SUBSEQUENT_NSVS
31 //#define DISABLE_AUDIO
33 /* max bytes to crawl for trying to resync
34 * stupid streaming servers don't start at chunk boundaries...
36 #define NSV_MAX_RESYNC (500*1024)
37 #define NSV_MAX_RESYNC_TRIES 300
40 * First version by Francois Revol - revol@free.fr
42 * (1) http://www.multimedia.cx/nsv-format.txt
43 * seems someone came to the same conclusions as me, and updated it:
44 * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
45 * http://www.stud.ktu.lt/~vitslav/nsv/
47 * (3) http://ultravox.aol.com/NSVFormat.rtf
49 * (S1) http://www.nullsoft.com/nsv/samples/
50 * http://www.nullsoft.com/nsv/samples/faster.nsv
51 * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
55 * notes on the header (Francois Revol):
57 * It is followed by strings, then a table, but nothing tells
58 * where the table begins according to (1). After checking faster.nsv,
59 * I believe NVSf[16-19] gives the size of the strings data
60 * (that is the offset of the data table after the header).
61 * After checking all samples from (S1) all confirms this.
63 * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
64 * I noticed there was about 1 NVSs chunk/s, so I ran
65 * strings faster.nsv | grep NSVs | wc -l
66 * which gave me 180. That leads me to think that NSVf[12-15] might be the
67 * file length in milliseconds.
69 * 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
70 * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
72 * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
73 * so the header seems to not be mandatory. (for streaming).
75 * index slice duration check (excepts nsvtrailer.nsv):
76 * for f in [^n]*.nsv; do
77 * DUR="$(avconv -i "$f" 2> /dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"
78 * IC="$(avconv -i "$f" 2> /dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"
79 * echo "duration $DUR, slite time $(($DUR/$IC))"
85 * - handle timestamps !!!
87 * - mime-type in probe()
93 uint32_t chunk_tag; /* 'NSVf' */
95 uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
96 uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
97 uint32_t info_strings_size; /* size of the info strings */ //unknown2;
98 uint32_t table_entries;
99 uint32_t table_entries_used; /* the left ones should be -1 */
103 uint32_t chunk_tag; /* 'NSVs' */
104 uint32_t v4cc; /* or 'NONE' */
105 uint32_t a4cc; /* or 'NONE' */
106 uint16_t vwidth; /* assert(vwidth%16==0) */
107 uint16_t vheight; /* assert(vheight%16==0) */
108 uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
112 struct nsv_avchunk_header {
113 uint8_t vchunk_size_lsb;
114 uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
115 uint16_t achunk_size;
118 struct nsv_pcm_header {
119 uint8_t bits_per_sample;
120 uint8_t channel_count;
121 uint16_t sample_rate;
125 /* variation from avi.h */
126 /*typedef struct CodecTag {
133 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
134 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
135 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
136 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
137 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
138 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
139 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
141 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
142 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
144 /* hardcoded stream indexes */
145 #define NSV_ST_VIDEO 0
146 #define NSV_ST_AUDIO 1
147 #define NSV_ST_SUBT 2
160 typedef struct NSVStream {
161 int frame_offset; /* current frame (video) or byte (audio) counter
162 (used to compute the pts) */
165 int sample_size; /* audio only data */
168 int new_frame_offset; /* temporary storage (used during seek) */
169 int cum_len; /* temporary storage (used during seek) */
175 uint32_t *nsvs_file_offset;
177 enum NSVStatus state;
178 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
182 uint16_t vwidth, vheight;
184 AVRational framerate;
185 uint32_t *nsvs_timestamps;
186 //DVDemuxContext* dv_demux;
189 static const AVCodecTag nsv_codec_video_tags[] = {
190 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
191 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
192 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
193 { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
194 { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
195 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
196 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
197 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
198 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
200 { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
201 { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
203 { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
204 { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
205 { AV_CODEC_ID_NONE, 0 },
208 static const AVCodecTag nsv_codec_audio_tags[] = {
209 { AV_CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
210 { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
211 { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
212 { AV_CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
213 { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
214 { AV_CODEC_ID_NONE, 0 },
217 //static int nsv_load_index(AVFormatContext *s);
218 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
220 #define print_tag(str, tag, size) \
221 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
224 (tag >> 16) & 0xff, \
227 /* try to find something we recognize, and set the state accordingly */
228 static int nsv_resync(AVFormatContext *s)
230 NSVContext *nsv = s->priv_data;
231 AVIOContext *pb = s->pb;
235 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
237 //nsv->state = NSV_UNSYNC;
239 for (i = 0; i < NSV_MAX_RESYNC; i++) {
240 if (pb->eof_reached) {
241 av_dlog(s, "NSV EOF\n");
242 nsv->state = NSV_UNSYNC;
248 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
251 if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
252 av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
253 nsv->state = NSV_FOUND_BEEF;
256 /* we read as big endian, thus the MK*BE* */
257 if (v == TB_NSVF) { /* NSVf */
258 av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
259 nsv->state = NSV_FOUND_NSVF;
262 if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
263 av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
264 nsv->state = NSV_FOUND_NSVS;
269 av_dlog(s, "NSV sync lost\n");
273 static int nsv_parse_NSVf_header(AVFormatContext *s)
275 NSVContext *nsv = s->priv_data;
276 AVIOContext *pb = s->pb;
277 unsigned int av_unused file_size;
282 int table_entries_used;
284 av_dlog(s, "%s()\n", __FUNCTION__);
286 nsv->state = NSV_UNSYNC; /* in case we fail */
288 size = avio_rl32(pb);
291 nsv->NSVf_end = size;
293 //s->file_size = (uint32_t)avio_rl32(pb);
294 file_size = (uint32_t)avio_rl32(pb);
295 av_dlog(s, "NSV NSVf chunk_size %u\n", size);
296 av_dlog(s, "NSV NSVf file_size %u\n", file_size);
298 nsv->duration = duration = avio_rl32(pb); /* in ms */
299 av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
300 // XXX: store it in AVStreams
302 strings_size = avio_rl32(pb);
303 table_entries = avio_rl32(pb);
304 table_entries_used = avio_rl32(pb);
305 av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
306 strings_size, table_entries, table_entries_used);
310 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
312 if (strings_size > 0) {
313 char *strings; /* last byte will be '\0' to play safe with str*() */
318 p = strings = av_mallocz((size_t)strings_size + 1);
320 return AVERROR(ENOMEM);
321 endp = strings + strings_size;
322 avio_read(pb, strings, strings_size);
325 p++; /* strip out spaces */
330 if (!p || p >= endp-2)
335 p = strchr(p, quote);
339 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
340 av_dict_set(&s->metadata, token, value, 0);
347 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
349 if (table_entries_used > 0) {
351 nsv->index_entries = table_entries_used;
352 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
354 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
355 if (!nsv->nsvs_file_offset)
356 return AVERROR(ENOMEM);
358 for(i=0;i<table_entries_used;i++)
359 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
361 if(table_entries > table_entries_used &&
362 avio_rl32(pb) == MKTAG('T','O','C','2')) {
363 nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
364 if (!nsv->nsvs_timestamps)
365 return AVERROR(ENOMEM);
366 for(i=0;i<table_entries_used;i++) {
367 nsv->nsvs_timestamps[i] = avio_rl32(pb);
372 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
374 #ifdef DEBUG_DUMP_INDEX
375 #define V(v) ((v<0x20 || v > 127)?'.':v)
377 av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
378 av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
379 for (i = 0; i < table_entries; i++) {
381 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
383 av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
384 "%c%c%c%c%c%c%c%c\n",
385 nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
386 b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
387 V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
389 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
393 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
397 nsv->state = NSV_HAS_READ_NSVF;
401 static int nsv_parse_NSVs_header(AVFormatContext *s)
403 NSVContext *nsv = s->priv_data;
404 AVIOContext *pb = s->pb;
406 uint16_t vwidth, vheight;
407 AVRational framerate;
411 av_dlog(s, "%s()\n", __FUNCTION__);
413 vtag = avio_rl32(pb);
414 atag = avio_rl32(pb);
415 vwidth = avio_rl16(pb);
416 vheight = avio_rl16(pb);
419 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
420 if(i&0x80) { /* odd way of giving native framerates from docs */
422 if(t<16) framerate = (AVRational){1, t+1};
423 else framerate = (AVRational){t-15, 1};
426 framerate.num *= 1000;
427 framerate.den *= 1001;
430 if((i&3)==3) framerate.num *= 24;
431 else if((i&3)==2) framerate.num *= 25;
432 else framerate.num *= 30;
435 framerate= (AVRational){i, 1};
437 nsv->avsync = avio_rl16(pb);
438 nsv->framerate = framerate;
440 print_tag("NSV NSVs vtag", vtag, 0);
441 print_tag("NSV NSVs atag", atag, 0);
442 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
444 /* XXX change to ap != NULL ? */
445 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
448 nsv->vwidth = vwidth;
449 nsv->vheight = vwidth;
450 if (vtag != T_NONE) {
452 st = avformat_new_stream(s, NULL);
456 st->id = NSV_ST_VIDEO;
457 nst = av_mallocz(sizeof(NSVStream));
461 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
462 st->codec->codec_tag = vtag;
463 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
464 st->codec->width = vwidth;
465 st->codec->height = vheight;
466 st->codec->bits_per_coded_sample = 24; /* depth XXX */
468 avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
470 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
472 for(i=0;i<nsv->index_entries;i++) {
473 if(nsv->nsvs_timestamps) {
474 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
475 0, 0, AVINDEX_KEYFRAME);
477 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
478 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
482 if (atag != T_NONE) {
483 #ifndef DISABLE_AUDIO
484 st = avformat_new_stream(s, NULL);
488 st->id = NSV_ST_AUDIO;
489 nst = av_mallocz(sizeof(NSVStream));
493 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
494 st->codec->codec_tag = atag;
495 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
497 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
499 /* set timebase to common denominator of ms and framerate */
500 avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
502 st->duration = (int64_t)nsv->duration * framerate.num;
505 #ifdef CHECK_SUBSEQUENT_NSVS
507 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
508 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
511 #endif /* CHECK_SUBSEQUENT_NSVS */
514 nsv->state = NSV_HAS_READ_NSVS;
518 nsv->state = NSV_UNSYNC;
522 static int nsv_read_header(AVFormatContext *s)
524 NSVContext *nsv = s->priv_data;
527 av_dlog(s, "%s()\n", __FUNCTION__);
528 av_dlog(s, "filename '%s'\n", s->filename);
530 nsv->state = NSV_UNSYNC;
531 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
533 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
534 if (nsv_resync(s) < 0)
536 if (nsv->state == NSV_FOUND_NSVF) {
537 err = nsv_parse_NSVf_header(s);
541 /* we need the first NSVs also... */
542 if (nsv->state == NSV_FOUND_NSVS) {
543 err = nsv_parse_NSVs_header(s);
546 break; /* we just want the first one */
549 if (s->nb_streams < 1) /* no luck so far */
551 /* now read the first chunk, so we can attempt to decode more info */
552 err = nsv_read_chunk(s, 1);
554 av_dlog(s, "parsed header\n");
558 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
560 NSVContext *nsv = s->priv_data;
561 AVIOContext *pb = s->pb;
562 AVStream *st[2] = {NULL, NULL};
566 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
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 uint32_t av_unused auxtag;
600 auxsize = avio_rl16(pb);
601 auxtag = avio_rl32(pb);
602 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
604 ((auxtag >> 8) & 0x0ff),
605 ((auxtag >> 16) & 0x0ff),
606 ((auxtag >> 24) & 0x0ff),
608 avio_skip(pb, auxsize);
609 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
614 if (!vsize && !asize) {
615 nsv->state = NSV_UNSYNC;
616 goto null_chunk_retry;
619 /* map back streams to v,a */
620 if (s->nb_streams > 0)
621 st[s->streams[0]->id] = s->streams[0];
622 if (s->nb_streams > 1)
623 st[s->streams[1]->id] = s->streams[1];
625 if (vsize && st[NSV_ST_VIDEO]) {
626 nst = st[NSV_ST_VIDEO]->priv_data;
627 pkt = &nsv->ahead[NSV_ST_VIDEO];
628 av_get_packet(pb, pkt, vsize);
629 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
630 pkt->dts = nst->frame_offset;
631 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
632 for (i = 0; i < FFMIN(8, vsize); i++)
633 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
636 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
638 if (asize && st[NSV_ST_AUDIO]) {
639 nst = st[NSV_ST_AUDIO]->priv_data;
640 pkt = &nsv->ahead[NSV_ST_AUDIO];
641 /* read raw audio specific header on the first audio chunk... */
642 /* on ALL audio chunks ?? seems so! */
643 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
648 channels = avio_r8(pb);
649 samplerate = avio_rl16(pb);
651 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
653 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
655 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
657 bps /= channels; // ???
659 st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8;
660 samplerate /= 4;/* UGH ??? XXX */
662 st[NSV_ST_AUDIO]->codec->channels = channels;
663 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
664 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
667 av_get_packet(pb, pkt, asize);
668 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
669 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
670 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
671 /* on a nsvs frame we have new information on a/v sync */
672 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
673 pkt->dts *= (int64_t)1000 * nsv->framerate.den;
674 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
675 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
680 nsv->state = NSV_UNSYNC;
685 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
687 NSVContext *nsv = s->priv_data;
690 av_dlog(s, "%s()\n", __FUNCTION__);
692 /* in case we don't already have something to eat ... */
693 if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
694 err = nsv_read_chunk(s, 0);
698 /* now pick one of the plates */
699 for (i = 0; i < 2; i++) {
700 if (nsv->ahead[i].data) {
701 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
702 /* avoid the cost of new_packet + memcpy(->data) */
703 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
704 nsv->ahead[i].data = NULL; /* we ate that one */
709 /* this restaurant is not approvisionned :^] */
713 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
715 NSVContext *nsv = s->priv_data;
716 AVStream *st = s->streams[stream_index];
717 NSVStream *nst = st->priv_data;
720 index = av_index_search_timestamp(st, timestamp, flags);
724 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
727 nst->frame_offset = st->index_entries[index].timestamp;
728 nsv->state = NSV_UNSYNC;
732 static int nsv_read_close(AVFormatContext *s)
735 NSVContext *nsv = s->priv_data;
737 av_freep(&nsv->nsvs_file_offset);
738 av_freep(&nsv->nsvs_timestamps);
739 if (nsv->ahead[0].data)
740 av_free_packet(&nsv->ahead[0]);
741 if (nsv->ahead[1].data)
742 av_free_packet(&nsv->ahead[1]);
746 for(i=0;i<s->nb_streams;i++) {
747 AVStream *st = s->streams[i];
748 NSVStream *ast = st->priv_data;
750 av_free(ast->index_entries);
753 av_free(st->codec->palctrl);
760 static int nsv_probe(AVProbeData *p)
764 int vsize, asize, auxcount;
766 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
767 /* check file header */
768 /* streamed files might not have any header */
769 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
770 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
771 return AVPROBE_SCORE_MAX;
772 /* XXX: do streamed files always start at chunk boundary ?? */
773 /* or do we need to search NSVs in the byte stream ? */
774 /* seems the servers don't bother starting clean chunks... */
775 /* sometimes even the first header is at 9KB or something :^) */
776 for (i = 1; i < p->buf_size - 3; i++) {
777 if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' &&
778 p->buf[i+2] == 'V' && p->buf[i+3] == 's') {
779 score = AVPROBE_SCORE_MAX/5;
780 /* Get the chunk size and check if at the end we are getting 0xBEEF */
781 auxcount = p->buf[i+19];
782 vsize = p->buf[i+20] | p->buf[i+21] << 8;
783 asize = p->buf[i+22] | p->buf[i+23] << 8;
784 vsize = (vsize << 4) | (auxcount >> 4);
785 if ((asize + vsize + i + 23) < p->buf_size - 2) {
786 if (p->buf[i+23+asize+vsize+1] == 0xEF &&
787 p->buf[i+23+asize+vsize+2] == 0xBE)
788 return AVPROBE_SCORE_MAX-20;
792 /* so we'll have more luck on extension... */
793 if (av_match_ext(p->filename, "nsv"))
794 return AVPROBE_SCORE_MAX/2;
795 /* FIXME: add mime-type check */
799 AVInputFormat ff_nsv_demuxer = {
801 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
802 .priv_data_size = sizeof(NSVContext),
803 .read_probe = nsv_probe,
804 .read_header = nsv_read_header,
805 .read_packet = nsv_read_packet,
806 .read_close = nsv_read_close,
807 .read_seek = nsv_read_seek,