1/*
2 * NSV demuxer
3 * Copyright (c) 2004 The FFmpeg Project
4 *
5 * first version by Francois Revol <revol@free.fr>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#include "libavutil/attributes.h"
25#include "libavutil/mathematics.h"
26#include "avformat.h"
27#include "internal.h"
28#include "libavutil/dict.h"
29#include "libavutil/intreadwrite.h"
30
31/* max bytes to crawl for trying to resync
32 * stupid streaming servers don't start at chunk boundaries...
33 */
34#define NSV_MAX_RESYNC (500*1024)
35#define NSV_MAX_RESYNC_TRIES 300
36
37/*
38 * References:
39 * (1) http://www.multimedia.cx/nsv-format.txt
40 * seems someone came to the same conclusions as me, and updated it:
41 * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
42 *     http://www.stud.ktu.lt/~vitslav/nsv/
43 * official docs
44 * (3) http://ultravox.aol.com/NSVFormat.rtf
45 * Sample files:
46 * (S1) http://www.nullsoft.com/nsv/samples/
47 * http://www.nullsoft.com/nsv/samples/faster.nsv
48 * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
49 */
50
51/*
52 * notes on the header (Francois Revol):
53 *
54 * It is followed by strings, then a table, but nothing tells
55 * where the table begins according to (1). After checking faster.nsv,
56 * I believe NVSf[16-19] gives the size of the strings data
57 * (that is the offset of the data table after the header).
58 * After checking all samples from (S1) all confirms this.
59 *
60 * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
61 * I noticed there was about 1 NVSs chunk/s, so I ran
62 * strings faster.nsv | grep NSVs | wc -l
63 * which gave me 180. That leads me to think that NSVf[12-15] might be the
64 * file length in milliseconds.
65 * Let's try that:
66 * 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
67 * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
68 *
69 * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
70 * so the header seems to not be mandatory. (for streaming).
71 *
72 * index slice duration check (excepts nsvtrailer.nsv):
73 * 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
74 */
75
76/*
77 * TODO:
78 * - handle timestamps !!!
79 * - use index
80 * - mime-type in probe()
81 * - seek
82 */
83
84#if 0
85struct NSVf_header {
86    uint32_t chunk_tag; /* 'NSVf' */
87    uint32_t chunk_size;
88    uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
89    uint32_t file_length; //unknown1;  /* what about MSB of file_size ? */
90    uint32_t info_strings_size; /* size of the info strings */ //unknown2;
91    uint32_t table_entries;
92    uint32_t table_entries_used; /* the left ones should be -1 */
93};
94
95struct NSVs_header {
96    uint32_t chunk_tag; /* 'NSVs' */
97    uint32_t v4cc;      /* or 'NONE' */
98    uint32_t a4cc;      /* or 'NONE' */
99    uint16_t vwidth;    /* av_assert(vwidth%16==0) */
100    uint16_t vheight;   /* av_assert(vheight%16==0) */
101    uint8_t framerate;  /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
102    uint16_t unknown;
103};
104
105struct nsv_avchunk_header {
106    uint8_t vchunk_size_lsb;
107    uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
108    uint16_t achunk_size;
109};
110
111struct nsv_pcm_header {
112    uint8_t bits_per_sample;
113    uint8_t channel_count;
114    uint16_t sample_rate;
115};
116#endif
117
118/* variation from avi.h */
119/*typedef struct CodecTag {
120    int id;
121    unsigned int tag;
122} CodecTag;*/
123
124/* tags */
125
126#define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
127#define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
128#define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
129#define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
130#define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
131#define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
132#define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
133
134#define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
135#define TB_NSVS MKBETAG('N', 'S', 'V', 's')
136
137/* hardcoded stream indexes */
138#define NSV_ST_VIDEO 0
139#define NSV_ST_AUDIO 1
140#define NSV_ST_SUBT 2
141
142enum NSVStatus {
143    NSV_UNSYNC,
144    NSV_FOUND_NSVF,
145    NSV_HAS_READ_NSVF,
146    NSV_FOUND_NSVS,
147    NSV_HAS_READ_NSVS,
148    NSV_FOUND_BEEF,
149    NSV_GOT_VIDEO,
150    NSV_GOT_AUDIO,
151};
152
153typedef struct NSVStream {
154    int frame_offset; /* current frame (video) or byte (audio) counter
155                         (used to compute the pts) */
156    int scale;
157    int rate;
158    int sample_size; /* audio only data */
159    int start;
160
161    int new_frame_offset; /* temporary storage (used during seek) */
162    int cum_len; /* temporary storage (used during seek) */
163} NSVStream;
164
165typedef struct {
166    int  base_offset;
167    int  NSVf_end;
168    uint32_t *nsvs_file_offset;
169    int index_entries;
170    enum NSVStatus state;
171    AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
172    /* cached */
173    int64_t duration;
174    uint32_t vtag, atag;
175    uint16_t vwidth, vheight;
176    int16_t avsync;
177    AVRational framerate;
178    uint32_t *nsvs_timestamps;
179    //DVDemuxContext* dv_demux;
180} NSVContext;
181
182static const AVCodecTag nsv_codec_video_tags[] = {
183    { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
184    { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
185    { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
186    { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
187    { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
188    { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
189    { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
190    { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
191    { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
192    { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') },
193/*
194    { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
195    { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
196*/
197    { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
198    { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
199    { AV_CODEC_ID_NONE, 0 },
200};
201
202static const AVCodecTag nsv_codec_audio_tags[] = {
203    { AV_CODEC_ID_MP3,       MKTAG('M', 'P', '3', ' ') },
204    { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', ' ') },
205    { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', 'P') },
206    { AV_CODEC_ID_AAC,       MKTAG('V', 'L', 'B', ' ') },
207    { AV_CODEC_ID_SPEEX,     MKTAG('S', 'P', 'X', ' ') },
208    { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
209    { AV_CODEC_ID_NONE,      0 },
210};
211
212//static int nsv_load_index(AVFormatContext *s);
213static int nsv_read_chunk(AVFormatContext *s, int fill_header);
214
215#define print_tag(str, tag, size)       \
216    av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
217            str, tag & 0xff,            \
218            (tag >> 8) & 0xff,          \
219            (tag >> 16) & 0xff,         \
220            (tag >> 24) & 0xff);
221
222/* try to find something we recognize, and set the state accordingly */
223static int nsv_resync(AVFormatContext *s)
224{
225    NSVContext *nsv = s->priv_data;
226    AVIOContext *pb = s->pb;
227    uint32_t v = 0;
228    int i;
229
230    av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
231
232    //nsv->state = NSV_UNSYNC;
233
234    for (i = 0; i < NSV_MAX_RESYNC; i++) {
235        if (url_feof(pb)) {
236            av_dlog(s, "NSV EOF\n");
237            nsv->state = NSV_UNSYNC;
238            return -1;
239        }
240        v <<= 8;
241        v |= avio_r8(pb);
242        if (i < 8) {
243            av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
244        }
245
246        if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
247            av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
248            nsv->state = NSV_FOUND_BEEF;
249            return 0;
250        }
251        /* we read as big-endian, thus the MK*BE* */
252        if (v == TB_NSVF) { /* NSVf */
253            av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
254            nsv->state = NSV_FOUND_NSVF;
255            return 0;
256        }
257        if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
258            av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
259            nsv->state = NSV_FOUND_NSVS;
260            return 0;
261        }
262
263    }
264    av_dlog(s, "NSV sync lost\n");
265    return -1;
266}
267
268static int nsv_parse_NSVf_header(AVFormatContext *s)
269{
270    NSVContext *nsv = s->priv_data;
271    AVIOContext *pb = s->pb;
272    unsigned int av_unused file_size;
273    unsigned int size;
274    int64_t duration;
275    int strings_size;
276    int table_entries;
277    int table_entries_used;
278
279    av_dlog(s, "%s()\n", __FUNCTION__);
280
281    nsv->state = NSV_UNSYNC; /* in case we fail */
282
283    size = avio_rl32(pb);
284    if (size < 28)
285        return -1;
286    nsv->NSVf_end = size;
287
288    //s->file_size = (uint32_t)avio_rl32(pb);
289    file_size = (uint32_t)avio_rl32(pb);
290    av_dlog(s, "NSV NSVf chunk_size %u\n", size);
291    av_dlog(s, "NSV NSVf file_size %u\n", file_size);
292
293    nsv->duration = duration = avio_rl32(pb); /* in ms */
294    av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
295    // XXX: store it in AVStreams
296
297    strings_size = avio_rl32(pb);
298    table_entries = avio_rl32(pb);
299    table_entries_used = avio_rl32(pb);
300    av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
301            strings_size, table_entries, table_entries_used);
302    if (url_feof(pb))
303        return -1;
304
305    av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
306
307    if (strings_size > 0) {
308        char *strings; /* last byte will be '\0' to play safe with str*() */
309        char *p, *endp;
310        char *token, *value;
311        char quote;
312
313        p = strings = av_mallocz((size_t)strings_size + 1);
314        if (!p)
315            return AVERROR(ENOMEM);
316        endp = strings + strings_size;
317        avio_read(pb, strings, strings_size);
318        while (p < endp) {
319            while (*p == ' ')
320                p++; /* strip out spaces */
321            if (p >= endp-2)
322                break;
323            token = p;
324            p = strchr(p, '=');
325            if (!p || p >= endp-2)
326                break;
327            *p++ = '\0';
328            quote = *p++;
329            value = p;
330            p = strchr(p, quote);
331            if (!p || p >= endp)
332                break;
333            *p++ = '\0';
334            av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
335            av_dict_set(&s->metadata, token, value, 0);
336        }
337        av_free(strings);
338    }
339    if (url_feof(pb))
340        return -1;
341
342    av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
343
344    if (table_entries_used > 0) {
345        int i;
346        nsv->index_entries = table_entries_used;
347        if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
348            return -1;
349        nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
350        if (!nsv->nsvs_file_offset)
351            return AVERROR(ENOMEM);
352
353        for(i=0;i<table_entries_used;i++)
354            nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
355
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            if (!nsv->nsvs_timestamps)
360                return AVERROR(ENOMEM);
361            for(i=0;i<table_entries_used;i++) {
362                nsv->nsvs_timestamps[i] = avio_rl32(pb);
363            }
364        }
365    }
366
367    av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
368
369    avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
370
371    if (url_feof(pb))
372        return -1;
373    nsv->state = NSV_HAS_READ_NSVF;
374    return 0;
375}
376
377static int nsv_parse_NSVs_header(AVFormatContext *s)
378{
379    NSVContext *nsv = s->priv_data;
380    AVIOContext *pb = s->pb;
381    uint32_t vtag, atag;
382    uint16_t vwidth, vheight;
383    AVRational framerate;
384    int i;
385    AVStream *st;
386    NSVStream *nst;
387    av_dlog(s, "%s()\n", __FUNCTION__);
388
389    vtag = avio_rl32(pb);
390    atag = avio_rl32(pb);
391    vwidth = avio_rl16(pb);
392    vheight = avio_rl16(pb);
393    i = avio_r8(pb);
394
395    av_dlog(s, "NSV NSVs framerate code %2x\n", i);
396    if(i&0x80) { /* odd way of giving native framerates from docs */
397        int t=(i & 0x7F)>>2;
398        if(t<16) framerate = (AVRational){1, t+1};
399        else     framerate = (AVRational){t-15, 1};
400
401        if(i&1){
402            framerate.num *= 1000;
403            framerate.den *= 1001;
404        }
405
406        if((i&3)==3)      framerate.num *= 24;
407        else if((i&3)==2) framerate.num *= 25;
408        else              framerate.num *= 30;
409    }
410    else
411        framerate= (AVRational){i, 1};
412
413    nsv->avsync = avio_rl16(pb);
414    nsv->framerate = framerate;
415
416    print_tag("NSV NSVs vtag", vtag, 0);
417    print_tag("NSV NSVs atag", atag, 0);
418    av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
419
420    /* XXX change to ap != NULL ? */
421    if (s->nb_streams == 0) { /* streams not yet published, let's do that */
422        nsv->vtag = vtag;
423        nsv->atag = atag;
424        nsv->vwidth = vwidth;
425        nsv->vheight = vwidth;
426        if (vtag != T_NONE) {
427            int i;
428            st = avformat_new_stream(s, NULL);
429            if (!st)
430                goto fail;
431
432            st->id = NSV_ST_VIDEO;
433            nst = av_mallocz(sizeof(NSVStream));
434            if (!nst)
435                goto fail;
436            st->priv_data = nst;
437            st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
438            st->codec->codec_tag = vtag;
439            st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
440            st->codec->width = vwidth;
441            st->codec->height = vheight;
442            st->codec->bits_per_coded_sample = 24; /* depth XXX */
443
444            avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
445            st->start_time = 0;
446            st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
447
448            for(i=0;i<nsv->index_entries;i++) {
449                if(nsv->nsvs_timestamps) {
450                    av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
451                                       0, 0, AVINDEX_KEYFRAME);
452                } else {
453                    int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
454                    av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
455                }
456            }
457        }
458        if (atag != T_NONE) {
459            st = avformat_new_stream(s, NULL);
460            if (!st)
461                goto fail;
462
463            st->id = NSV_ST_AUDIO;
464            nst = av_mallocz(sizeof(NSVStream));
465            if (!nst)
466                goto fail;
467            st->priv_data = nst;
468            st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
469            st->codec->codec_tag = atag;
470            st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
471
472            st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
473
474            /* set timebase to common denominator of ms and framerate */
475            avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
476            st->start_time = 0;
477            st->duration = (int64_t)nsv->duration * framerate.num;
478        }
479    } else {
480        if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
481            av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
482            //return -1;
483        }
484    }
485
486    nsv->state = NSV_HAS_READ_NSVS;
487    return 0;
488fail:
489    /* XXX */
490    nsv->state = NSV_UNSYNC;
491    return -1;
492}
493
494static int nsv_read_header(AVFormatContext *s)
495{
496    NSVContext *nsv = s->priv_data;
497    int i, err;
498
499    av_dlog(s, "%s()\n", __FUNCTION__);
500    av_dlog(s, "filename '%s'\n", s->filename);
501
502    nsv->state = NSV_UNSYNC;
503    nsv->ahead[0].data = nsv->ahead[1].data = NULL;
504
505    for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
506        if (nsv_resync(s) < 0)
507            return -1;
508        if (nsv->state == NSV_FOUND_NSVF) {
509            err = nsv_parse_NSVf_header(s);
510            if (err < 0)
511                return err;
512        }
513            /* we need the first NSVs also... */
514        if (nsv->state == NSV_FOUND_NSVS) {
515            err = nsv_parse_NSVs_header(s);
516            if (err < 0)
517                return err;
518            break; /* we just want the first one */
519        }
520    }
521    if (s->nb_streams < 1) /* no luck so far */
522        return -1;
523    /* now read the first chunk, so we can attempt to decode more info */
524    err = nsv_read_chunk(s, 1);
525
526    av_dlog(s, "parsed header\n");
527    return err;
528}
529
530static int nsv_read_chunk(AVFormatContext *s, int fill_header)
531{
532    NSVContext *nsv = s->priv_data;
533    AVIOContext *pb = s->pb;
534    AVStream *st[2] = {NULL, NULL};
535    NSVStream *nst;
536    AVPacket *pkt;
537    int i, err = 0;
538    uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
539    uint32_t vsize;
540    uint16_t asize;
541    uint16_t auxsize;
542
543    av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
544
545    if (nsv->ahead[0].data || nsv->ahead[1].data)
546        return 0; //-1; /* hey! eat what you've in your plate first! */
547
548null_chunk_retry:
549    if (url_feof(pb))
550        return -1;
551
552    for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
553        err = nsv_resync(s);
554    if (err < 0)
555        return err;
556    if (nsv->state == NSV_FOUND_NSVS)
557        err = nsv_parse_NSVs_header(s);
558    if (err < 0)
559        return err;
560    if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
561        return -1;
562
563    auxcount = avio_r8(pb);
564    vsize = avio_rl16(pb);
565    asize = avio_rl16(pb);
566    vsize = (vsize << 4) | (auxcount >> 4);
567    auxcount &= 0x0f;
568    av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
569    /* skip aux stuff */
570    for (i = 0; i < auxcount; i++) {
571        uint32_t av_unused auxtag;
572        auxsize = avio_rl16(pb);
573        auxtag = avio_rl32(pb);
574        av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
575              (auxtag & 0x0ff),
576              ((auxtag >> 8) & 0x0ff),
577              ((auxtag >> 16) & 0x0ff),
578              ((auxtag >> 24) & 0x0ff),
579              auxsize);
580        avio_skip(pb, auxsize);
581        vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
582    }
583
584    if (url_feof(pb))
585        return -1;
586    if (!vsize && !asize) {
587        nsv->state = NSV_UNSYNC;
588        goto null_chunk_retry;
589    }
590
591    /* map back streams to v,a */
592    if (s->nb_streams > 0)
593        st[s->streams[0]->id] = s->streams[0];
594    if (s->nb_streams > 1)
595        st[s->streams[1]->id] = s->streams[1];
596
597    if (vsize && st[NSV_ST_VIDEO]) {
598        nst = st[NSV_ST_VIDEO]->priv_data;
599        pkt = &nsv->ahead[NSV_ST_VIDEO];
600        av_get_packet(pb, pkt, vsize);
601        pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
602        pkt->dts = nst->frame_offset;
603        pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
604        for (i = 0; i < FFMIN(8, vsize); i++)
605            av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
606    }
607    if(st[NSV_ST_VIDEO])
608        ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
609
610    if (asize && st[NSV_ST_AUDIO]) {
611        nst = st[NSV_ST_AUDIO]->priv_data;
612        pkt = &nsv->ahead[NSV_ST_AUDIO];
613        /* read raw audio specific header on the first audio chunk... */
614        /* on ALL audio chunks ?? seems so! */
615        if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
616            uint8_t bps;
617            uint8_t channels;
618            uint16_t samplerate;
619            bps = avio_r8(pb);
620            channels = avio_r8(pb);
621            samplerate = avio_rl16(pb);
622            asize-=4;
623            av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
624            if (fill_header) {
625                st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
626                if (bps != 16) {
627                    av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
628                }
629                if(channels)
630                    bps /= channels; // ???
631                else
632                    av_log(s, AV_LOG_WARNING, "Channels is 0\n");
633                if (bps == 8)
634                    st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8;
635                samplerate /= 4;/* UGH ??? XXX */
636                channels = 1;
637                st[NSV_ST_AUDIO]->codec->channels = channels;
638                st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
639                av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
640            }
641        }
642        av_get_packet(pb, pkt, asize);
643        pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
644        pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
645        if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
646            /* on a nsvs frame we have new information on a/v sync */
647            pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
648            pkt->dts *= (int64_t)1000        * nsv->framerate.den;
649            pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
650            av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
651        }
652        nst->frame_offset++;
653    }
654
655    nsv->state = NSV_UNSYNC;
656    return 0;
657}
658
659
660static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
661{
662    NSVContext *nsv = s->priv_data;
663    int i, err = 0;
664
665    av_dlog(s, "%s()\n", __FUNCTION__);
666
667    /* in case we don't already have something to eat ... */
668    if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
669        err = nsv_read_chunk(s, 0);
670    if (err < 0)
671        return err;
672
673    /* now pick one of the plates */
674    for (i = 0; i < 2; i++) {
675        if (nsv->ahead[i].data) {
676            av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
677            /* avoid the cost of new_packet + memcpy(->data) */
678            memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
679            nsv->ahead[i].data = NULL; /* we ate that one */
680            return pkt->size;
681        }
682    }
683
684    /* this restaurant is not approvisionned :^] */
685    return -1;
686}
687
688static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
689{
690    NSVContext *nsv = s->priv_data;
691    AVStream *st = s->streams[stream_index];
692    NSVStream *nst = st->priv_data;
693    int index;
694
695    index = av_index_search_timestamp(st, timestamp, flags);
696    if(index < 0)
697        return -1;
698
699    if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
700        return -1;
701
702    nst->frame_offset = st->index_entries[index].timestamp;
703    nsv->state = NSV_UNSYNC;
704    return 0;
705}
706
707static int nsv_read_close(AVFormatContext *s)
708{
709    NSVContext *nsv = s->priv_data;
710
711    av_freep(&nsv->nsvs_file_offset);
712    av_freep(&nsv->nsvs_timestamps);
713    if (nsv->ahead[0].data)
714        av_free_packet(&nsv->ahead[0]);
715    if (nsv->ahead[1].data)
716        av_free_packet(&nsv->ahead[1]);
717    return 0;
718}
719
720static int nsv_probe(AVProbeData *p)
721{
722    int i, score = 0;
723
724    av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
725    /* check file header */
726    /* streamed files might not have any header */
727    if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
728        p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
729        return AVPROBE_SCORE_MAX;
730    /* XXX: do streamed files always start at chunk boundary ?? */
731    /* or do we need to search NSVs in the byte stream ? */
732    /* seems the servers don't bother starting clean chunks... */
733    /* sometimes even the first header is at 9KB or something :^) */
734    for (i = 1; i < p->buf_size - 3; i++) {
735        if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {
736            /* Get the chunk size and check if at the end we are getting 0xBEEF */
737            int vsize = AV_RL24(p->buf+i+19) >> 4;
738            int asize = AV_RL16(p->buf+i+22);
739            int offset = i + 23 + asize + vsize + 1;
740            if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)
741                return 4*AVPROBE_SCORE_MAX/5;
742            score = AVPROBE_SCORE_MAX/5;
743        }
744    }
745    /* so we'll have more luck on extension... */
746    if (av_match_ext(p->filename, "nsv"))
747        return AVPROBE_SCORE_EXTENSION;
748    /* FIXME: add mime-type check */
749    return score;
750}
751
752AVInputFormat ff_nsv_demuxer = {
753    .name           = "nsv",
754    .long_name      = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
755    .priv_data_size = sizeof(NSVContext),
756    .read_probe     = nsv_probe,
757    .read_header    = nsv_read_header,
758    .read_packet    = nsv_read_packet,
759    .read_close     = nsv_read_close,
760    .read_seek      = nsv_read_seek,
761};
762