avformat: Add ff_configure_buffers_for_index()

This allows configuring the io buffer in such way that few seeks are needed for playback

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2015-06-02 18:30:07 +02:00 committed by Michael Niedermayer
parent 1aab5d8ab1
commit b183fb4767
2 changed files with 41 additions and 0 deletions

View File

@ -254,6 +254,8 @@ int ff_add_index_entry(AVIndexEntry **index_entries,
unsigned int *index_entries_allocated_size,
int64_t pos, int64_t timestamp, int size, int distance, int flags);
void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
/**
* Add a new chapter.
*

View File

@ -1781,6 +1781,45 @@ int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
return m;
}
void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance)
{
int ist1, ist2;
int64_t pos_delta = 0;
for (ist1 = 0; ist1 < s->nb_streams; ist1++) {
AVStream *st1 = s->streams[ist1];
for (ist2 = 0; ist2 < s->nb_streams; ist2++) {
AVStream *st2 = s->streams[ist2];
int i1, i2;
if (ist1 == ist2)
continue;
for (i1 = i2 = 0; i1 < st1->nb_index_entries; i1++) {
AVIndexEntry *e1 = &st1->index_entries[i1];
int64_t e1_pts = av_rescale_q(e1->timestamp, st1->time_base, AV_TIME_BASE_Q);
for (; i2 < st2->nb_index_entries; i2++) {
AVIndexEntry *e2 = &st2->index_entries[i2];
int64_t e2_pts = av_rescale_q(e2->timestamp, st2->time_base, AV_TIME_BASE_Q);
if (e2_pts - e1_pts < time_tolerance)
continue;
pos_delta = FFMAX(pos_delta, e1->pos - e2->pos);
break;
}
}
}
}
pos_delta *= 2;
/* XXX This could be adjusted depending on protocol*/
if (s->pb->buffer_size < pos_delta && pos_delta < (1<<24)) {
av_log(s, AV_LOG_VERBOSE, "Reconfiguring buffers to size %"PRId64"\n", pos_delta);
ffio_set_buf_size(s->pb, pos_delta);
s->pb->short_seek_threshold = FFMAX(s->pb->short_seek_threshold, pos_delta/2);
}
}
int av_index_search_timestamp(AVStream *st, int64_t wanted_timestamp, int flags)
{
return ff_index_search_timestamp(st->index_entries, st->nb_index_entries,