3 * Copyright (c) 2004 The FFmpeg Project
5 * This file is part of FFmpeg.
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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"
27 #include "libavutil/intreadwrite.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 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
81 * - handle timestamps !!!
83 * - mime-type in probe()
89 uint32_t chunk_tag; /* 'NSVf' */
91 uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
92 uint32_t file_length; //unknown1; /* what about MSB of file_size ? */
93 uint32_t info_strings_size; /* size of the info strings */ //unknown2;
94 uint32_t table_entries;
95 uint32_t table_entries_used; /* the left ones should be -1 */
99 uint32_t chunk_tag; /* 'NSVs' */
100 uint32_t v4cc; /* or 'NONE' */
101 uint32_t a4cc; /* or 'NONE' */
102 uint16_t vwidth; /* assert(vwidth%16==0) */
103 uint16_t vheight; /* assert(vheight%16==0) */
104 uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
108 struct nsv_avchunk_header {
109 uint8_t vchunk_size_lsb;
110 uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
111 uint16_t achunk_size;
114 struct nsv_pcm_header {
115 uint8_t bits_per_sample;
116 uint8_t channel_count;
117 uint16_t sample_rate;
121 /* variation from avi.h */
122 /*typedef struct CodecTag {
129 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
130 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
131 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
132 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
133 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
134 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
135 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
137 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
138 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
140 /* hardcoded stream indexes */
141 #define NSV_ST_VIDEO 0
142 #define NSV_ST_AUDIO 1
143 #define NSV_ST_SUBT 2
156 typedef struct NSVStream {
157 int frame_offset; /* current frame (video) or byte (audio) counter
158 (used to compute the pts) */
161 int sample_size; /* audio only data */
164 int new_frame_offset; /* temporary storage (used during seek) */
165 int cum_len; /* temporary storage (used during seek) */
171 uint32_t *nsvs_file_offset;
173 enum NSVStatus state;
174 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
178 uint16_t vwidth, vheight;
180 AVRational framerate;
181 uint32_t *nsvs_timestamps;
182 //DVDemuxContext* dv_demux;
185 static const AVCodecTag nsv_codec_video_tags[] = {
186 { CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
187 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
188 { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
189 { CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
190 { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
191 { CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
192 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
193 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
194 { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
196 { CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
197 { CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
199 { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
200 { CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
201 { CODEC_ID_NONE, 0 },
204 static const AVCodecTag nsv_codec_audio_tags[] = {
205 { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },
206 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },
207 { CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },
208 { CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },
209 { CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
210 { CODEC_ID_NONE, 0 },
213 //static int nsv_load_index(AVFormatContext *s);
214 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
216 #define print_tag(str, tag, size) \
217 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
220 (tag >> 16) & 0xff, \
223 /* try to find something we recognize, and set the state accordingly */
224 static int nsv_resync(AVFormatContext *s)
226 NSVContext *nsv = s->priv_data;
227 AVIOContext *pb = s->pb;
231 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
233 //nsv->state = NSV_UNSYNC;
235 for (i = 0; i < NSV_MAX_RESYNC; i++) {
237 av_dlog(s, "NSV EOF\n");
238 nsv->state = NSV_UNSYNC;
244 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
247 if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
248 av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
249 nsv->state = NSV_FOUND_BEEF;
252 /* we read as big endian, thus the MK*BE* */
253 if (v == TB_NSVF) { /* NSVf */
254 av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
255 nsv->state = NSV_FOUND_NSVF;
258 if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
259 av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
260 nsv->state = NSV_FOUND_NSVS;
265 av_dlog(s, "NSV sync lost\n");
269 static int nsv_parse_NSVf_header(AVFormatContext *s, AVFormatParameters *ap)
271 NSVContext *nsv = s->priv_data;
272 AVIOContext *pb = s->pb;
273 unsigned int av_unused file_size;
278 int table_entries_used;
280 av_dlog(s, "%s()\n", __FUNCTION__);
282 nsv->state = NSV_UNSYNC; /* in case we fail */
284 size = avio_rl32(pb);
287 nsv->NSVf_end = size;
289 //s->file_size = (uint32_t)avio_rl32(pb);
290 file_size = (uint32_t)avio_rl32(pb);
291 av_dlog(s, "NSV NSVf chunk_size %u\n", size);
292 av_dlog(s, "NSV NSVf file_size %u\n", file_size);
294 nsv->duration = duration = avio_rl32(pb); /* in ms */
295 av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
296 // XXX: store it in AVStreams
298 strings_size = avio_rl32(pb);
299 table_entries = avio_rl32(pb);
300 table_entries_used = avio_rl32(pb);
301 av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
302 strings_size, table_entries, table_entries_used);
306 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
308 if (strings_size > 0) {
309 char *strings; /* last byte will be '\0' to play safe with str*() */
314 p = strings = av_mallocz(strings_size + 1);
315 endp = strings + strings_size;
316 avio_read(pb, strings, strings_size);
319 p++; /* strip out spaces */
324 if (!p || p >= endp-2)
329 p = strchr(p, quote);
333 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
334 av_dict_set(&s->metadata, token, value, 0);
341 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
343 if (table_entries_used > 0) {
345 nsv->index_entries = table_entries_used;
346 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
348 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
350 for(i=0;i<table_entries_used;i++)
351 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
353 if(table_entries > table_entries_used &&
354 avio_rl32(pb) == MKTAG('T','O','C','2')) {
355 nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
356 for(i=0;i<table_entries_used;i++) {
357 nsv->nsvs_timestamps[i] = avio_rl32(pb);
362 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
364 #ifdef DEBUG_DUMP_INDEX
365 #define V(v) ((v<0x20 || v > 127)?'.':v)
367 av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
368 av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
369 for (i = 0; i < table_entries; i++) {
371 avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
373 av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
374 "%c%c%c%c%c%c%c%c\n",
375 nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
376 b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
377 V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
379 //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
383 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
387 nsv->state = NSV_HAS_READ_NSVF;
391 static int nsv_parse_NSVs_header(AVFormatContext *s, AVFormatParameters *ap)
393 NSVContext *nsv = s->priv_data;
394 AVIOContext *pb = s->pb;
396 uint16_t vwidth, vheight;
397 AVRational framerate;
401 av_dlog(s, "%s()\n", __FUNCTION__);
403 vtag = avio_rl32(pb);
404 atag = avio_rl32(pb);
405 vwidth = avio_rl16(pb);
406 vheight = avio_rl16(pb);
409 av_dlog(s, "NSV NSVs framerate code %2x\n", i);
410 if(i&0x80) { /* odd way of giving native framerates from docs */
412 if(t<16) framerate = (AVRational){1, t+1};
413 else framerate = (AVRational){t-15, 1};
416 framerate.num *= 1000;
417 framerate.den *= 1001;
420 if((i&3)==3) framerate.num *= 24;
421 else if((i&3)==2) framerate.num *= 25;
422 else framerate.num *= 30;
425 framerate= (AVRational){i, 1};
427 nsv->avsync = avio_rl16(pb);
428 nsv->framerate = framerate;
430 print_tag("NSV NSVs vtag", vtag, 0);
431 print_tag("NSV NSVs atag", atag, 0);
432 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
434 /* XXX change to ap != NULL ? */
435 if (s->nb_streams == 0) { /* streams not yet published, let's do that */
438 nsv->vwidth = vwidth;
439 nsv->vheight = vwidth;
440 if (vtag != T_NONE) {
442 st = avformat_new_stream(s, NULL);
446 st->id = NSV_ST_VIDEO;
447 nst = av_mallocz(sizeof(NSVStream));
451 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
452 st->codec->codec_tag = vtag;
453 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
454 st->codec->width = vwidth;
455 st->codec->height = vheight;
456 st->codec->bits_per_coded_sample = 24; /* depth XXX */
458 avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
460 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
462 for(i=0;i<nsv->index_entries;i++) {
463 if(nsv->nsvs_timestamps) {
464 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
465 0, 0, AVINDEX_KEYFRAME);
467 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
468 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
472 if (atag != T_NONE) {
473 #ifndef DISABLE_AUDIO
474 st = avformat_new_stream(s, NULL);
478 st->id = NSV_ST_AUDIO;
479 nst = av_mallocz(sizeof(NSVStream));
483 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
484 st->codec->codec_tag = atag;
485 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
487 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
489 /* set timebase to common denominator of ms and framerate */
490 avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
492 st->duration = (int64_t)nsv->duration * framerate.num;
495 #ifdef CHECK_SUBSEQUENT_NSVS
497 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
498 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
501 #endif /* CHECK_SUBSEQUENT_NSVS */
504 nsv->state = NSV_HAS_READ_NSVS;
508 nsv->state = NSV_UNSYNC;
512 static int nsv_read_header(AVFormatContext *s, AVFormatParameters *ap)
514 NSVContext *nsv = s->priv_data;
517 av_dlog(s, "%s()\n", __FUNCTION__);
518 av_dlog(s, "filename '%s'\n", s->filename);
520 nsv->state = NSV_UNSYNC;
521 nsv->ahead[0].data = nsv->ahead[1].data = NULL;
523 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
524 if (nsv_resync(s) < 0)
526 if (nsv->state == NSV_FOUND_NSVF)
527 err = nsv_parse_NSVf_header(s, ap);
528 /* we need the first NSVs also... */
529 if (nsv->state == NSV_FOUND_NSVS) {
530 err = nsv_parse_NSVs_header(s, ap);
531 break; /* we just want the first one */
534 if (s->nb_streams < 1) /* no luck so far */
536 /* now read the first chunk, so we can attempt to decode more info */
537 err = nsv_read_chunk(s, 1);
539 av_dlog(s, "parsed header\n");
543 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
545 NSVContext *nsv = s->priv_data;
546 AVIOContext *pb = s->pb;
547 AVStream *st[2] = {NULL, NULL};
551 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
555 uint32_t av_unused auxtag;
557 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
559 if (nsv->ahead[0].data || nsv->ahead[1].data)
560 return 0; //-1; /* hey! eat what you've in your plate first! */
566 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
570 if (nsv->state == NSV_FOUND_NSVS)
571 err = nsv_parse_NSVs_header(s, NULL);
574 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
577 auxcount = avio_r8(pb);
578 vsize = avio_rl16(pb);
579 asize = avio_rl16(pb);
580 vsize = (vsize << 4) | (auxcount >> 4);
582 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
584 for (i = 0; i < auxcount; i++) {
585 auxsize = avio_rl16(pb);
586 auxtag = avio_rl32(pb);
587 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
589 ((auxtag >> 8) & 0x0ff),
590 ((auxtag >> 16) & 0x0ff),
591 ((auxtag >> 24) & 0x0ff),
593 avio_skip(pb, auxsize);
594 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
599 if (!vsize && !asize) {
600 nsv->state = NSV_UNSYNC;
601 goto null_chunk_retry;
604 /* map back streams to v,a */
606 st[s->streams[0]->id] = s->streams[0];
608 st[s->streams[1]->id] = s->streams[1];
610 if (vsize/* && st[NSV_ST_VIDEO]*/) {
611 nst = st[NSV_ST_VIDEO]->priv_data;
612 pkt = &nsv->ahead[NSV_ST_VIDEO];
613 av_get_packet(pb, pkt, vsize);
614 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
615 pkt->dts = nst->frame_offset;
616 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
617 for (i = 0; i < FFMIN(8, vsize); i++)
618 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
621 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
623 if (asize/*st[NSV_ST_AUDIO]*/) {
624 nst = st[NSV_ST_AUDIO]->priv_data;
625 pkt = &nsv->ahead[NSV_ST_AUDIO];
626 /* read raw audio specific header on the first audio chunk... */
627 /* on ALL audio chunks ?? seems so! */
628 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
633 channels = avio_r8(pb);
634 samplerate = avio_rl16(pb);
636 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
638 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
640 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
642 bps /= channels; // ???
644 st[NSV_ST_AUDIO]->codec->codec_id = CODEC_ID_PCM_U8;
645 samplerate /= 4;/* UGH ??? XXX */
647 st[NSV_ST_AUDIO]->codec->channels = channels;
648 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
649 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
652 av_get_packet(pb, pkt, asize);
653 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
654 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
655 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
656 /* on a nsvs frame we have new information on a/v sync */
657 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
658 pkt->dts *= (int64_t)1000 * nsv->framerate.den;
659 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
660 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
665 nsv->state = NSV_UNSYNC;
670 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
672 NSVContext *nsv = s->priv_data;
675 av_dlog(s, "%s()\n", __FUNCTION__);
677 /* in case we don't already have something to eat ... */
678 if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
679 err = nsv_read_chunk(s, 0);
683 /* now pick one of the plates */
684 for (i = 0; i < 2; i++) {
685 if (nsv->ahead[i].data) {
686 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
687 /* avoid the cost of new_packet + memcpy(->data) */
688 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
689 nsv->ahead[i].data = NULL; /* we ate that one */
694 /* this restaurant is not approvisionned :^] */
698 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
700 NSVContext *nsv = s->priv_data;
701 AVStream *st = s->streams[stream_index];
702 NSVStream *nst = st->priv_data;
705 index = av_index_search_timestamp(st, timestamp, flags);
709 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
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 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
750 /* check file header */
751 /* streamed files might not have any header */
752 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
753 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
754 return AVPROBE_SCORE_MAX;
755 /* XXX: do streamed files always start at chunk boundary ?? */
756 /* or do we need to search NSVs in the byte stream ? */
757 /* seems the servers don't bother starting clean chunks... */
758 /* sometimes even the first header is at 9KB or something :^) */
759 for (i = 1; i < p->buf_size - 3; i++) {
760 if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {
761 /* Get the chunk size and check if at the end we are getting 0xBEEF */
762 int vsize = AV_RL24(p->buf+i+19) >> 4;
763 int asize = AV_RL16(p->buf+i+22);
764 int offset = i + 23 + asize + vsize + 1;
765 if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)
766 return 4*AVPROBE_SCORE_MAX/5;
767 score = AVPROBE_SCORE_MAX/5;
770 /* so we'll have more luck on extension... */
771 if (av_match_ext(p->filename, "nsv"))
772 return AVPROBE_SCORE_MAX/2;
773 /* FIXME: add mime-type check */
777 AVInputFormat ff_nsv_demuxer = {
779 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
780 .priv_data_size = sizeof(NSVContext),
781 .read_probe = nsv_probe,
782 .read_header = nsv_read_header,
783 .read_packet = nsv_read_packet,
784 .read_close = nsv_read_close,
785 .read_seek = nsv_read_seek,