virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

rudimentary binary seek

Browse Source 
Originally committed as revision 6382 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Baptiste Coudurier 2006-09-29 14:28:55 +00:00
parent 1159f6340a
commit 3a6ccf4f3e
1 changed files with 30 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
libavformat/mxf.c
View File

@ -976,6 +976,35 @@ static int mxf_probe(AVProbeData *p) {
return 0;
}
/* rudimentary binary seek */
/* XXX: use MXF Index */
static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_time, int flags)
{
AVStream *st = s->streams[stream_index];
offset_t pos = url_ftell(&s->pb);
int64_t seconds;
int i;
if (!s->bit_rate || sample_time < 0)
return -1;
seconds = av_rescale(sample_time, st->time_base.num, st->time_base.den);
url_fseek(&s->pb, (s->bit_rate * seconds) >> 3, SEEK_SET);
/* sync on KLV essence element */
for (i = 0; i < 12 && url_ftell(&s->pb) < s->file_size; i++) {
int b = get_byte(&s->pb);
if (b == mxf_essence_element_key[0])
i = 0;
else if (b != mxf_essence_element_key[i])
i = -1;
}
if (i == 12) { /* found KLV key */
url_fseek(&s->pb, -12, SEEK_CUR);
av_update_cur_dts(s, st, sample_time);
return 0;
}
url_fseek(&s->pb, pos, SEEK_SET);
return -1;
}
AVInputFormat mxf_demuxer = {
"mxf",
@ -985,5 +1014,5 @@ AVInputFormat mxf_demuxer = {
mxf_read_header,
mxf_read_packet,
mxf_read_close,
NULL,
mxf_read_seek,
};