RepoMirrors
/
mpv
mirror of https://github.com/mpv-player/mpv
1
0
Fork 0
Code Issues Releases Wiki Activity

demux: optimize seeks within readahead cache 

If a suitable keyframe cannot be found in each stream's
readahead cache, fallback to a regular seek.
This commit is contained in:
Aman Gupta 2017-10-13 15:16:32 -07:00 committed by wm4
parent 044af63d98
commit 83c9f169c4
1 changed files with 103 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

98
demux/demux.c
View File

@ -225,6 +225,7 @@ struct demux_stream {
static void demuxer_sort_chapters(demuxer_t *demuxer);
static void *demux_thread(void *pctx);
static void update_cache(struct demux_internal *in);
static int cached_demux_control(struct demux_internal *in, int cmd, void *arg);
// called locked
static void ds_flush(struct demux_stream *ds)
@ -1425,10 +1426,8 @@ struct demuxer *demux_open_url(const char *url,
return d;
}
static void flush_locked(demuxer_t *demuxer)
static void flush_locked_state(demuxer_t *demuxer)
{
for (int n = 0; n < demuxer->in->num_streams; n++)
ds_flush(demuxer->in->streams[n]->ds);
demuxer->in->warned_queue_overflow = false;
demuxer->in->eof = false;
demuxer->in->last_eof = false;
@ -1436,6 +1435,13 @@ static void flush_locked(demuxer_t *demuxer)
demuxer->filepos = -1; // implicitly synchronized
}
static void flush_locked(demuxer_t *demuxer)
{
for (int n = 0; n < demuxer->in->num_streams; n++)
ds_flush(demuxer->in->streams[n]->ds);
flush_locked_state(demuxer);
}
// clear the packet queues
void demux_flush(demuxer_t *demuxer)
{
@ -1444,6 +1450,87 @@ void demux_flush(demuxer_t *demuxer)
pthread_mutex_unlock(&demuxer->in->lock);
}
static bool demux_seek_cache_maybe(demuxer_t *demuxer, double seek_pts, int flags)
{
struct demux_internal *in = demuxer->in;
struct demux_ctrl_reader_state rstate;
bool seeked = true;
double seek_pts_offset = MP_ADD_PTS(seek_pts, -in->ts_offset);
assert(demuxer == in->d_user);
if ((flags & SEEK_FACTOR))
return false;
if (cached_demux_control(in, DEMUXER_CTRL_GET_READER_STATE, &rstate) < 0)
return false;
MP_VERBOSE(in, "in-cache seek range = %f <-> %f (%f)\n",
rstate.ts_range[0], rstate.ts_range[1], seek_pts);
if (seek_pts < rstate.ts_range[0] ||
seek_pts > rstate.ts_range[1])
return false;
MP_VERBOSE(in, "in-cache seek is possible..\n");
for (int n = 0; n < in->num_streams; n++) {
struct demux_stream *ds = in->streams[n]->ds;
demux_packet_t *dp = ds->head;
bool found_keyframe = false;
int idx = 0;
if (!ds->active || (ds->eof && !ds->head))
continue;
// find idx of pts
while (dp) {
demux_packet_t *dn = dp->next;
if (dp->pts >= seek_pts_offset)
break;
idx++;
dp = dn;
}
if ((flags & SEEK_FORWARD)) {
// increment idx until keyframe
while (dp) {
demux_packet_t *dn = dp->next;
if (dp->keyframe) {
found_keyframe = true;
break;
}
idx++;
dp = dn;
}
} else {
// find last keyframe before idx
int i = 0, key_idx = 0;
dp = ds->head;
while (dp && i < idx) {
demux_packet_t *dn = dp->next;
if (dp->keyframe) {
found_keyframe = true;
key_idx = i;
}
i++;
dp = dn;
}
idx = key_idx;
}
if (!found_keyframe) {
seeked = false;
break;
}
while (idx-- > 0) {
demux_packet_t *pkt = dequeue_packet(ds);
free_demux_packet(pkt);
}
assert(ds->head && ds->head->keyframe);
}
return seeked;
}
int demux_seek(demuxer_t *demuxer, double seek_pts, int flags)
{
struct demux_internal *in = demuxer->in;
@ -1465,6 +1552,10 @@ int demux_seek(demuxer_t *demuxer, double seek_pts, int flags)
MP_VERBOSE(in, "queuing seek to %f%s\n", seek_pts,
in->seeking ? " (cascade)" : "");
if (demux_seek_cache_maybe(demuxer, seek_pts, flags)) {
MP_VERBOSE(in, "in-cache seek worked!\n");
flush_locked_state(demuxer);
} else {
flush_locked(demuxer);
in->seeking = true;
in->seek_flags = flags;
@ -1474,6 +1565,7 @@ int demux_seek(demuxer_t *demuxer, double seek_pts, int flags)
if (!in->threading)
execute_seek(in);
}
pthread_cond_signal(&in->wakeup);
pthread_mutex_unlock(&in->lock);