static int ogg_read_page(AVFormatContext *s, int *str)
{
AVIOContext *bc = s->pb;
struct ogg *ogg = s->priv_data;
struct ogg_stream *os;
int ret, i = 0;
int flags, nsegs;
uint64_t gp;
uint32_t serial;
int size, idx;
uint8_t sync[4];
int sp = 0;
ret = avio_read (bc, sync, 4);
if (ret < 4)
return ret < 0 ? ret : AVERROR_EOF;
do{
int c;
if (sync[sp & 3] == 'O' &&
sync[(sp + 1) & 3] == 'g' &&
sync[(sp + 2) & 3] == 'g' && sync[(sp + 3) & 3] == 'S')
break;
c = avio_r8(bc);
if (url_feof(bc))
return AVERROR_EOF;
sync[sp++ & 3] = c;
}while (i++ < MAX_PAGE_SIZE);
if (i >= MAX_PAGE_SIZE){
av_log (s, AV_LOG_INFO, "ogg, can't find sync word\n");
return AVERROR_INVALIDDATA;
}
if (avio_r8(bc) != 0) /* version */
return AVERROR_INVALIDDATA;
flags = avio_r8(bc);
gp = avio_rl64 (bc);
serial = avio_rl32 (bc);
avio_skip(bc, 8); /* seq, crc */
nsegs = avio_r8(bc);
idx = ogg_find_stream (ogg, serial);
if (idx < 0){
if (ogg->headers) {
int n;
for (n = 0; n < ogg->nstreams; n++) {
av_freep(&ogg->streams[n].buf);
av_freep(&ogg->streams[n].private);
}
ogg->curidx = -1;
ogg->nstreams = 0;
idx = ogg_new_stream(s, serial, 0);
} else {
static int skeleton_header(AVFormatContext *s, int idx)
{
struct ogg *ogg = s->priv_data;
struct ogg_stream *os = ogg->streams + idx;
AVStream *st = s->streams[idx];
uint8_t *buf = os->buf + os->pstart;
int version_major, version_minor;
int64_t start_num, start_den;
uint64_t start_granule;
int target_idx, start_time;
strcpy(st->codec->codec_name, "skeleton");
st->codec->codec_type = AVMEDIA_TYPE_DATA;
if (os->psize < 8)
return -1;
if (!strncmp(buf, "fishead", 8)) {
if (os->psize < 64)
return -1;
version_major = AV_RL16(buf+8);
version_minor = AV_RL16(buf+10);
if (version_major != 3) {
av_log(s, AV_LOG_WARNING, "Unknown skeleton version %d.%d\n",
version_major, version_minor);
return -1;
}
// This is the overall start time. We use it for the start time of
// of the skeleton stream since if left unset lavf assumes 0,
// which we don't want since skeleton is timeless
// FIXME: the real meaning of this field is "start playback at
// this time which can be in the middle of a packet
start_num = AV_RL64(buf+12);
start_den = AV_RL64(buf+20);
if (start_den) {
int base_den;
av_reduce(&start_time, &base_den, start_num, start_den, INT_MAX);
avpriv_set_pts_info(st, 64, 1, base_den);
os->lastpts =
st->start_time = start_time;
}
} else if (!strncmp(buf, "fisbone", 8)) {
if (os->psize < 52)
return -1;
target_idx = ogg_find_stream(ogg, AV_RL32(buf+12));
start_granule = AV_RL64(buf+36);
if (os->start_granule != OGG_NOGRANULE_VALUE) {
av_log_missing_feature(s,
"multiple fisbone for the same stream", 0);
return 1;
}
if (target_idx >= 0 && start_granule != OGG_NOGRANULE_VALUE) {
os->start_granule = start_granule;
}
}
return 1;
}
