FFmpeg: libavformat/nsvdec.c Source File

00001 /*
00002  * NSV demuxer
00003  * Copyright (c) 2004 The FFmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/attributes.h"
00023 #include "libavutil/mathematics.h"
00024 #include "avformat.h"
00025 #include "internal.h"
00026 #include "riff.h"
00027 #include "libavutil/dict.h"
00028 #include "libavutil/intreadwrite.h"
00029 
00030 //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!!
00031 #define CHECK_SUBSEQUENT_NSVS
00032 //#define DISABLE_AUDIO
00033 
00034 /* max bytes to crawl for trying to resync
00035  * stupid streaming servers don't start at chunk boundaries...
00036  */
00037 #define NSV_MAX_RESYNC (500*1024)
00038 #define NSV_MAX_RESYNC_TRIES 300
00039 
00040 /*
00041  * First version by Francois Revol - revol@free.fr
00042  * References:
00043  * (1) http://www.multimedia.cx/nsv-format.txt
00044  * seems someone came to the same conclusions as me, and updated it:
00045  * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt
00046  *     http://www.stud.ktu.lt/~vitslav/nsv/
00047  * official docs
00048  * (3) http://ultravox.aol.com/NSVFormat.rtf
00049  * Sample files:
00050  * (S1) http://www.nullsoft.com/nsv/samples/
00051  * http://www.nullsoft.com/nsv/samples/faster.nsv
00052  * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4
00053  */
00054 
00055 /*
00056  * notes on the header (Francois Revol):
00057  *
00058  * It is followed by strings, then a table, but nothing tells
00059  * where the table begins according to (1). After checking faster.nsv,
00060  * I believe NVSf[16-19] gives the size of the strings data
00061  * (that is the offset of the data table after the header).
00062  * After checking all samples from (S1) all confirms this.
00063  *
00064  * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,
00065  * I noticed there was about 1 NVSs chunk/s, so I ran
00066  * strings faster.nsv | grep NSVs | wc -l
00067  * which gave me 180. That leads me to think that NSVf[12-15] might be the
00068  * file length in milliseconds.
00069  * Let's try that:
00070  * 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
00071  * except for nstrailer (which doesn't have an NSVf header), it repports correct time.
00072  *
00073  * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,
00074  * so the header seems to not be mandatory. (for streaming).
00075  *
00076  * index slice duration check (excepts nsvtrailer.nsv):
00077  * 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
00078  */
00079 
00080 /*
00081  * TODO:
00082  * - handle timestamps !!!
00083  * - use index
00084  * - mime-type in probe()
00085  * - seek
00086  */
00087 
00088 #if 0
00089 struct NSVf_header {
00090     uint32_t chunk_tag; /* 'NSVf' */
00091     uint32_t chunk_size;
00092     uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */
00093     uint32_t file_length; //unknown1;  /* what about MSB of file_size ? */
00094     uint32_t info_strings_size; /* size of the info strings */ //unknown2;
00095     uint32_t table_entries;
00096     uint32_t table_entries_used; /* the left ones should be -1 */
00097 };
00098 
00099 struct NSVs_header {
00100     uint32_t chunk_tag; /* 'NSVs' */
00101     uint32_t v4cc;      /* or 'NONE' */
00102     uint32_t a4cc;      /* or 'NONE' */
00103     uint16_t vwidth;    /* av_assert(vwidth%16==0) */
00104     uint16_t vheight;   /* av_assert(vheight%16==0) */
00105     uint8_t framerate;  /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */
00106     uint16_t unknown;
00107 };
00108 
00109 struct nsv_avchunk_header {
00110     uint8_t vchunk_size_lsb;
00111     uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */
00112     uint16_t achunk_size;
00113 };
00114 
00115 struct nsv_pcm_header {
00116     uint8_t bits_per_sample;
00117     uint8_t channel_count;
00118     uint16_t sample_rate;
00119 };
00120 #endif
00121 
00122 /* variation from avi.h */
00123 /*typedef struct CodecTag {
00124     int id;
00125     unsigned int tag;
00126 } CodecTag;*/
00127 
00128 /* tags */
00129 
00130 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */
00131 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */
00132 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */
00133 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */
00134 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */
00135 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */
00136 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */
00137 
00138 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')
00139 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')
00140 
00141 /* hardcoded stream indexes */
00142 #define NSV_ST_VIDEO 0
00143 #define NSV_ST_AUDIO 1
00144 #define NSV_ST_SUBT 2
00145 
00146 enum NSVStatus {
00147     NSV_UNSYNC,
00148     NSV_FOUND_NSVF,
00149     NSV_HAS_READ_NSVF,
00150     NSV_FOUND_NSVS,
00151     NSV_HAS_READ_NSVS,
00152     NSV_FOUND_BEEF,
00153     NSV_GOT_VIDEO,
00154     NSV_GOT_AUDIO,
00155 };
00156 
00157 typedef struct NSVStream {
00158     int frame_offset; /* current frame (video) or byte (audio) counter
00159                          (used to compute the pts) */
00160     int scale;
00161     int rate;
00162     int sample_size; /* audio only data */
00163     int start;
00164 
00165     int new_frame_offset; /* temporary storage (used during seek) */
00166     int cum_len; /* temporary storage (used during seek) */
00167 } NSVStream;
00168 
00169 typedef struct {
00170     int  base_offset;
00171     int  NSVf_end;
00172     uint32_t *nsvs_file_offset;
00173     int index_entries;
00174     enum NSVStatus state;
00175     AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */
00176     /* cached */
00177     int64_t duration;
00178     uint32_t vtag, atag;
00179     uint16_t vwidth, vheight;
00180     int16_t avsync;
00181     AVRational framerate;
00182     uint32_t *nsvs_timestamps;
00183     //DVDemuxContext* dv_demux;
00184 } NSVContext;
00185 
00186 static const AVCodecTag nsv_codec_video_tags[] = {
00187     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },
00188     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },
00189     { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },
00190     { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },
00191     { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },
00192     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },
00193     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },
00194     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },
00195     { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },
00196     { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') },
00197 /*
00198     { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },
00199     { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },
00200 */
00201     { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */
00202     { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },
00203     { AV_CODEC_ID_NONE, 0 },
00204 };
00205 
00206 static const AVCodecTag nsv_codec_audio_tags[] = {
00207     { AV_CODEC_ID_MP3,       MKTAG('M', 'P', '3', ' ') },
00208     { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', ' ') },
00209     { AV_CODEC_ID_AAC,       MKTAG('A', 'A', 'C', 'P') },
00210     { AV_CODEC_ID_AAC,       MKTAG('V', 'L', 'B', ' ') },
00211     { AV_CODEC_ID_SPEEX,     MKTAG('S', 'P', 'X', ' ') },
00212     { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },
00213     { AV_CODEC_ID_NONE,      0 },
00214 };
00215 
00216 //static int nsv_load_index(AVFormatContext *s);
00217 static int nsv_read_chunk(AVFormatContext *s, int fill_header);
00218 
00219 #define print_tag(str, tag, size)       \
00220     av_dlog(NULL, "%s: tag=%c%c%c%c\n", \
00221             str, tag & 0xff,            \
00222             (tag >> 8) & 0xff,          \
00223             (tag >> 16) & 0xff,         \
00224             (tag >> 24) & 0xff);
00225 
00226 /* try to find something we recognize, and set the state accordingly */
00227 static int nsv_resync(AVFormatContext *s)
00228 {
00229     NSVContext *nsv = s->priv_data;
00230     AVIOContext *pb = s->pb;
00231     uint32_t v = 0;
00232     int i;
00233 
00234     av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);
00235 
00236     //nsv->state = NSV_UNSYNC;
00237 
00238     for (i = 0; i < NSV_MAX_RESYNC; i++) {
00239         if (url_feof(pb)) {
00240             av_dlog(s, "NSV EOF\n");
00241             nsv->state = NSV_UNSYNC;
00242             return -1;
00243         }
00244         v <<= 8;
00245         v |= avio_r8(pb);
00246         if (i < 8) {
00247             av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);
00248         }
00249 
00250         if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */
00251             av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);
00252             nsv->state = NSV_FOUND_BEEF;
00253             return 0;
00254         }
00255         /* we read as big endian, thus the MK*BE* */
00256         if (v == TB_NSVF) { /* NSVf */
00257             av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);
00258             nsv->state = NSV_FOUND_NSVF;
00259             return 0;
00260         }
00261         if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */
00262             av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);
00263             nsv->state = NSV_FOUND_NSVS;
00264             return 0;
00265         }
00266 
00267     }
00268     av_dlog(s, "NSV sync lost\n");
00269     return -1;
00270 }
00271 
00272 static int nsv_parse_NSVf_header(AVFormatContext *s)
00273 {
00274     NSVContext *nsv = s->priv_data;
00275     AVIOContext *pb = s->pb;
00276     unsigned int av_unused file_size;
00277     unsigned int size;
00278     int64_t duration;
00279     int strings_size;
00280     int table_entries;
00281     int table_entries_used;
00282 
00283     av_dlog(s, "%s()\n", __FUNCTION__);
00284 
00285     nsv->state = NSV_UNSYNC; /* in case we fail */
00286 
00287     size = avio_rl32(pb);
00288     if (size < 28)
00289         return -1;
00290     nsv->NSVf_end = size;
00291 
00292     //s->file_size = (uint32_t)avio_rl32(pb);
00293     file_size = (uint32_t)avio_rl32(pb);
00294     av_dlog(s, "NSV NSVf chunk_size %u\n", size);
00295     av_dlog(s, "NSV NSVf file_size %u\n", file_size);
00296 
00297     nsv->duration = duration = avio_rl32(pb); /* in ms */
00298     av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);
00299     // XXX: store it in AVStreams
00300 
00301     strings_size = avio_rl32(pb);
00302     table_entries = avio_rl32(pb);
00303     table_entries_used = avio_rl32(pb);
00304     av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",
00305             strings_size, table_entries, table_entries_used);
00306     if (url_feof(pb))
00307         return -1;
00308 
00309     av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));
00310 
00311     if (strings_size > 0) {
00312         char *strings; /* last byte will be '\0' to play safe with str*() */
00313         char *p, *endp;
00314         char *token, *value;
00315         char quote;
00316 
00317         p = strings = av_mallocz((size_t)strings_size + 1);
00318         if (!p)
00319             return AVERROR(ENOMEM);
00320         endp = strings + strings_size;
00321         avio_read(pb, strings, strings_size);
00322         while (p < endp) {
00323             while (*p == ' ')
00324                 p++; /* strip out spaces */
00325             if (p >= endp-2)
00326                 break;
00327             token = p;
00328             p = strchr(p, '=');
00329             if (!p || p >= endp-2)
00330                 break;
00331             *p++ = '\0';
00332             quote = *p++;
00333             value = p;
00334             p = strchr(p, quote);
00335             if (!p || p >= endp)
00336                 break;
00337             *p++ = '\0';
00338             av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);
00339             av_dict_set(&s->metadata, token, value, 0);
00340         }
00341         av_free(strings);
00342     }
00343     if (url_feof(pb))
00344         return -1;
00345 
00346     av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));
00347 
00348     if (table_entries_used > 0) {
00349         int i;
00350         nsv->index_entries = table_entries_used;
00351         if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))
00352             return -1;
00353         nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));
00354         if (!nsv->nsvs_file_offset)
00355             return AVERROR(ENOMEM);
00356 
00357         for(i=0;i<table_entries_used;i++)
00358             nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;
00359 
00360         if(table_entries > table_entries_used &&
00361            avio_rl32(pb) == MKTAG('T','O','C','2')) {
00362             nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));
00363             if (!nsv->nsvs_timestamps)
00364                 return AVERROR(ENOMEM);
00365             for(i=0;i<table_entries_used;i++) {
00366                 nsv->nsvs_timestamps[i] = avio_rl32(pb);
00367             }
00368         }
00369     }
00370 
00371     av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));
00372 
00373 #ifdef DEBUG_DUMP_INDEX
00374 #define V(v) ((v<0x20 || v > 127)?'.':v)
00375     /* dump index */
00376     av_dlog(s, "NSV %d INDEX ENTRIES:\n", table_entries);
00377     av_dlog(s, "NSV [dataoffset][fileoffset]\n", table_entries);
00378     for (i = 0; i < table_entries; i++) {
00379         unsigned char b[8];
00380         avio_seek(pb, size + nsv->nsvs_file_offset[i], SEEK_SET);
00381         avio_read(pb, b, 8);
00382         av_dlog(s, "NSV [0x%08lx][0x%08lx]: %02x %02x %02x %02x %02x %02x %02x %02x"
00383            "%c%c%c%c%c%c%c%c\n",
00384            nsv->nsvs_file_offset[i], size + nsv->nsvs_file_offset[i],
00385            b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7],
00386            V(b[0]), V(b[1]), V(b[2]), V(b[3]), V(b[4]), V(b[5]), V(b[6]), V(b[7]) );
00387     }
00388     //avio_seek(pb, size, SEEK_SET); /* go back to end of header */
00389 #undef V
00390 #endif
00391 
00392     avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */
00393 
00394     if (url_feof(pb))
00395         return -1;
00396     nsv->state = NSV_HAS_READ_NSVF;
00397     return 0;
00398 }
00399 
00400 static int nsv_parse_NSVs_header(AVFormatContext *s)
00401 {
00402     NSVContext *nsv = s->priv_data;
00403     AVIOContext *pb = s->pb;
00404     uint32_t vtag, atag;
00405     uint16_t vwidth, vheight;
00406     AVRational framerate;
00407     int i;
00408     AVStream *st;
00409     NSVStream *nst;
00410     av_dlog(s, "%s()\n", __FUNCTION__);
00411 
00412     vtag = avio_rl32(pb);
00413     atag = avio_rl32(pb);
00414     vwidth = avio_rl16(pb);
00415     vheight = avio_rl16(pb);
00416     i = avio_r8(pb);
00417 
00418     av_dlog(s, "NSV NSVs framerate code %2x\n", i);
00419     if(i&0x80) { /* odd way of giving native framerates from docs */
00420         int t=(i & 0x7F)>>2;
00421         if(t<16) framerate = (AVRational){1, t+1};
00422         else     framerate = (AVRational){t-15, 1};
00423 
00424         if(i&1){
00425             framerate.num *= 1000;
00426             framerate.den *= 1001;
00427         }
00428 
00429         if((i&3)==3)      framerate.num *= 24;
00430         else if((i&3)==2) framerate.num *= 25;
00431         else              framerate.num *= 30;
00432     }
00433     else
00434         framerate= (AVRational){i, 1};
00435 
00436     nsv->avsync = avio_rl16(pb);
00437     nsv->framerate = framerate;
00438 
00439     print_tag("NSV NSVs vtag", vtag, 0);
00440     print_tag("NSV NSVs atag", atag, 0);
00441     av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);
00442 
00443     /* XXX change to ap != NULL ? */
00444     if (s->nb_streams == 0) { /* streams not yet published, let's do that */
00445         nsv->vtag = vtag;
00446         nsv->atag = atag;
00447         nsv->vwidth = vwidth;
00448         nsv->vheight = vwidth;
00449         if (vtag != T_NONE) {
00450             int i;
00451             st = avformat_new_stream(s, NULL);
00452             if (!st)
00453                 goto fail;
00454 
00455             st->id = NSV_ST_VIDEO;
00456             nst = av_mallocz(sizeof(NSVStream));
00457             if (!nst)
00458                 goto fail;
00459             st->priv_data = nst;
00460             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00461             st->codec->codec_tag = vtag;
00462             st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);
00463             st->codec->width = vwidth;
00464             st->codec->height = vheight;
00465             st->codec->bits_per_coded_sample = 24; /* depth XXX */
00466 
00467             avpriv_set_pts_info(st, 64, framerate.den, framerate.num);
00468             st->start_time = 0;
00469             st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);
00470 
00471             for(i=0;i<nsv->index_entries;i++) {
00472                 if(nsv->nsvs_timestamps) {
00473                     av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],
00474                                        0, 0, AVINDEX_KEYFRAME);
00475                 } else {
00476                     int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);
00477                     av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);
00478                 }
00479             }
00480         }
00481         if (atag != T_NONE) {
00482 #ifndef DISABLE_AUDIO
00483             st = avformat_new_stream(s, NULL);
00484             if (!st)
00485                 goto fail;
00486 
00487             st->id = NSV_ST_AUDIO;
00488             nst = av_mallocz(sizeof(NSVStream));
00489             if (!nst)
00490                 goto fail;
00491             st->priv_data = nst;
00492             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00493             st->codec->codec_tag = atag;
00494             st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);
00495 
00496             st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */
00497 
00498             /* set timebase to common denominator of ms and framerate */
00499             avpriv_set_pts_info(st, 64, 1, framerate.num*1000);
00500             st->start_time = 0;
00501             st->duration = (int64_t)nsv->duration * framerate.num;
00502 #endif
00503         }
00504 #ifdef CHECK_SUBSEQUENT_NSVS
00505     } else {
00506         if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {
00507             av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");
00508             //return -1;
00509         }
00510 #endif /* CHECK_SUBSEQUENT_NSVS */
00511     }
00512 
00513     nsv->state = NSV_HAS_READ_NSVS;
00514     return 0;
00515 fail:
00516     /* XXX */
00517     nsv->state = NSV_UNSYNC;
00518     return -1;
00519 }
00520 
00521 static int nsv_read_header(AVFormatContext *s)
00522 {
00523     NSVContext *nsv = s->priv_data;
00524     int i, err;
00525 
00526     av_dlog(s, "%s()\n", __FUNCTION__);
00527     av_dlog(s, "filename '%s'\n", s->filename);
00528 
00529     nsv->state = NSV_UNSYNC;
00530     nsv->ahead[0].data = nsv->ahead[1].data = NULL;
00531 
00532     for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {
00533         if (nsv_resync(s) < 0)
00534             return -1;
00535         if (nsv->state == NSV_FOUND_NSVF) {
00536             err = nsv_parse_NSVf_header(s);
00537             if (err < 0)
00538                 return err;
00539         }
00540             /* we need the first NSVs also... */
00541         if (nsv->state == NSV_FOUND_NSVS) {
00542             err = nsv_parse_NSVs_header(s);
00543             if (err < 0)
00544                 return err;
00545             break; /* we just want the first one */
00546         }
00547     }
00548     if (s->nb_streams < 1) /* no luck so far */
00549         return -1;
00550     /* now read the first chunk, so we can attempt to decode more info */
00551     err = nsv_read_chunk(s, 1);
00552 
00553     av_dlog(s, "parsed header\n");
00554     return err;
00555 }
00556 
00557 static int nsv_read_chunk(AVFormatContext *s, int fill_header)
00558 {
00559     NSVContext *nsv = s->priv_data;
00560     AVIOContext *pb = s->pb;
00561     AVStream *st[2] = {NULL, NULL};
00562     NSVStream *nst;
00563     AVPacket *pkt;
00564     int i, err = 0;
00565     uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */
00566     uint32_t vsize;
00567     uint16_t asize;
00568     uint16_t auxsize;
00569 
00570     av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);
00571 
00572     if (nsv->ahead[0].data || nsv->ahead[1].data)
00573         return 0; //-1; /* hey! eat what you've in your plate first! */
00574 
00575 null_chunk_retry:
00576     if (url_feof(pb))
00577         return -1;
00578 
00579     for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)
00580         err = nsv_resync(s);
00581     if (err < 0)
00582         return err;
00583     if (nsv->state == NSV_FOUND_NSVS)
00584         err = nsv_parse_NSVs_header(s);
00585     if (err < 0)
00586         return err;
00587     if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)
00588         return -1;
00589 
00590     auxcount = avio_r8(pb);
00591     vsize = avio_rl16(pb);
00592     asize = avio_rl16(pb);
00593     vsize = (vsize << 4) | (auxcount >> 4);
00594     auxcount &= 0x0f;
00595     av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);
00596     /* skip aux stuff */
00597     for (i = 0; i < auxcount; i++) {
00598         uint32_t av_unused auxtag;
00599         auxsize = avio_rl16(pb);
00600         auxtag = avio_rl32(pb);
00601         av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",
00602               (auxtag & 0x0ff),
00603               ((auxtag >> 8) & 0x0ff),
00604               ((auxtag >> 16) & 0x0ff),
00605               ((auxtag >> 24) & 0x0ff),
00606               auxsize);
00607         avio_skip(pb, auxsize);
00608         vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */
00609     }
00610 
00611     if (url_feof(pb))
00612         return -1;
00613     if (!vsize && !asize) {
00614         nsv->state = NSV_UNSYNC;
00615         goto null_chunk_retry;
00616     }
00617 
00618     /* map back streams to v,a */
00619     if (s->nb_streams > 0)
00620         st[s->streams[0]->id] = s->streams[0];
00621     if (s->nb_streams > 1)
00622         st[s->streams[1]->id] = s->streams[1];
00623 
00624     if (vsize && st[NSV_ST_VIDEO]) {
00625         nst = st[NSV_ST_VIDEO]->priv_data;
00626         pkt = &nsv->ahead[NSV_ST_VIDEO];
00627         av_get_packet(pb, pkt, vsize);
00628         pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;
00629         pkt->dts = nst->frame_offset;
00630         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
00631         for (i = 0; i < FFMIN(8, vsize); i++)
00632             av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);
00633     }
00634     if(st[NSV_ST_VIDEO])
00635         ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
00636 
00637     if (asize && st[NSV_ST_AUDIO]) {
00638         nst = st[NSV_ST_AUDIO]->priv_data;
00639         pkt = &nsv->ahead[NSV_ST_AUDIO];
00640         /* read raw audio specific header on the first audio chunk... */
00641         /* on ALL audio chunks ?? seems so! */
00642         if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {
00643             uint8_t bps;
00644             uint8_t channels;
00645             uint16_t samplerate;
00646             bps = avio_r8(pb);
00647             channels = avio_r8(pb);
00648             samplerate = avio_rl16(pb);
00649             asize-=4;
00650             av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
00651             if (fill_header) {
00652                 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */
00653                 if (bps != 16) {
00654                     av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);
00655                 }
00656                 bps /= channels; // ???
00657                 if (bps == 8)
00658                     st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8;
00659                 samplerate /= 4;/* UGH ??? XXX */
00660                 channels = 1;
00661                 st[NSV_ST_AUDIO]->codec->channels = channels;
00662                 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;
00663                 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);
00664             }
00665         }
00666         av_get_packet(pb, pkt, asize);
00667         pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;
00668         pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */
00669         if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {
00670             /* on a nsvs frame we have new information on a/v sync */
00671             pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);
00672             pkt->dts *= (int64_t)1000        * nsv->framerate.den;
00673             pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;
00674             av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);
00675         }
00676         nst->frame_offset++;
00677     }
00678 
00679     nsv->state = NSV_UNSYNC;
00680     return 0;
00681 }
00682 
00683 
00684 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)
00685 {
00686     NSVContext *nsv = s->priv_data;
00687     int i, err = 0;
00688 
00689     av_dlog(s, "%s()\n", __FUNCTION__);
00690 
00691     /* in case we don't already have something to eat ... */
00692     if (nsv->ahead[0].data == NULL && nsv->ahead[1].data == NULL)
00693         err = nsv_read_chunk(s, 0);
00694     if (err < 0)
00695         return err;
00696 
00697     /* now pick one of the plates */
00698     for (i = 0; i < 2; i++) {
00699         if (nsv->ahead[i].data) {
00700             av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);
00701             /* avoid the cost of new_packet + memcpy(->data) */
00702             memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));
00703             nsv->ahead[i].data = NULL; /* we ate that one */
00704             return pkt->size;
00705         }
00706     }
00707 
00708     /* this restaurant is not approvisionned :^] */
00709     return -1;
00710 }
00711 
00712 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
00713 {
00714     NSVContext *nsv = s->priv_data;
00715     AVStream *st = s->streams[stream_index];
00716     NSVStream *nst = st->priv_data;
00717     int index;
00718 
00719     index = av_index_search_timestamp(st, timestamp, flags);
00720     if(index < 0)
00721         return -1;
00722 
00723     if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
00724         return -1;
00725 
00726     nst->frame_offset = st->index_entries[index].timestamp;
00727     nsv->state = NSV_UNSYNC;
00728     return 0;
00729 }
00730 
00731 static int nsv_read_close(AVFormatContext *s)
00732 {
00733 /*     int i; */
00734     NSVContext *nsv = s->priv_data;
00735 
00736     av_freep(&nsv->nsvs_file_offset);
00737     av_freep(&nsv->nsvs_timestamps);
00738     if (nsv->ahead[0].data)
00739         av_free_packet(&nsv->ahead[0]);
00740     if (nsv->ahead[1].data)
00741         av_free_packet(&nsv->ahead[1]);
00742 
00743 #if 0
00744 
00745     for(i=0;i<s->nb_streams;i++) {
00746         AVStream *st = s->streams[i];
00747         NSVStream *ast = st->priv_data;
00748         if(ast){
00749             av_free(ast->index_entries);
00750             av_free(ast);
00751         }
00752         av_free(st->codec->palctrl);
00753     }
00754 
00755 #endif
00756     return 0;
00757 }
00758 
00759 static int nsv_probe(AVProbeData *p)
00760 {
00761     int i, score = 0;
00762 
00763     av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);
00764     /* check file header */
00765     /* streamed files might not have any header */
00766     if (p->buf[0] == 'N' && p->buf[1] == 'S' &&
00767         p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))
00768         return AVPROBE_SCORE_MAX;
00769     /* XXX: do streamed files always start at chunk boundary ?? */
00770     /* or do we need to search NSVs in the byte stream ? */
00771     /* seems the servers don't bother starting clean chunks... */
00772     /* sometimes even the first header is at 9KB or something :^) */
00773     for (i = 1; i < p->buf_size - 3; i++) {
00774         if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {
00775             /* Get the chunk size and check if at the end we are getting 0xBEEF */
00776             int vsize = AV_RL24(p->buf+i+19) >> 4;
00777             int asize = AV_RL16(p->buf+i+22);
00778             int offset = i + 23 + asize + vsize + 1;
00779             if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)
00780                 return 4*AVPROBE_SCORE_MAX/5;
00781             score = AVPROBE_SCORE_MAX/5;
00782         }
00783     }
00784     /* so we'll have more luck on extension... */
00785     if (av_match_ext(p->filename, "nsv"))
00786         return AVPROBE_SCORE_MAX/2;
00787     /* FIXME: add mime-type check */
00788     return score;
00789 }
00790 
00791 AVInputFormat ff_nsv_demuxer = {
00792     .name           = "nsv",
00793     .long_name      = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),
00794     .priv_data_size = sizeof(NSVContext),
00795     .read_probe     = nsv_probe,
00796     .read_header    = nsv_read_header,
00797     .read_packet    = nsv_read_packet,
00798     .read_close     = nsv_read_close,
00799     .read_seek      = nsv_read_seek,
00800 };