make sure the check for valid timestamps does not accidentially search through

several hundered MB (e.g. happens under MinGW with certain DVDs due to movi_end
overflowing).


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@18073 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
reimar 2006-04-10 16:18:17 +00:00
parent 3e489b2da7
commit aaf067719b
1 changed files with 10 additions and 2 deletions

View File

@ -99,11 +99,14 @@ static int parse_psm(demuxer_t *demux, int len) {
return 1;
}
// 500000 is a wild guess
#define TIMESTAMP_PROBE_LEN 500000
/// Open an mpg physical stream
static demuxer_t* demux_mpg_open(demuxer_t* demuxer) {
stream_t *s = demuxer->stream;
off_t pos = stream_tell(s);
off_t end_seq_start = demuxer->movi_end-500000; // 500000 is a wild guess
off_t end_seq_start = demuxer->movi_end-TIMESTAMP_PROBE_LEN;
float half_pts = 0.0;
mpg_demuxer_t* mpg_d;
@ -114,13 +117,18 @@ static demuxer_t* demux_mpg_open(demuxer_t* demuxer) {
mpg_d->has_valid_timestamps = 1;
mpg_d->num_a_streams = 0;
if (demuxer->seekable && stream_tell(demuxer->stream) < end_seq_start) {
stream_seek(s,(pos + end_seq_start / 2));
off_t half_pos = pos + end_seq_start / 2;
stream_seek(s, half_pos);
while ((!s->eof) && ds_fill_buffer(demuxer->video) && half_pts == 0.0) {
half_pts = mpg_d->last_pts;
if (stream_tell(s) > half_pos + TIMESTAMP_PROBE_LEN)
break;
}
stream_seek(s,end_seq_start);
while ((!s->eof) && ds_fill_buffer(demuxer->video)) {
if (mpg_d->final_pts < mpg_d->last_pts) mpg_d->final_pts = mpg_d->last_pts;
if (stream_tell(s) > demuxer->movi_end)
break;
}
// educated guess about validity of timestamps
if (mpg_d->final_pts > 3 * half_pts || mpg_d->final_pts < 1.5 * half_pts) {