Improve seek speed.

[dcpomatic.git] / src / lib / player.cc

diff --git a/src/lib/player.cc b/src/lib/player.cc
index 0f2cc0365d642ca1489f07a757d143d7178e8583..e3d88a54c212dbe36e3225a1f337090d76050d13 100644 (file)
--- a/src/lib/player.cc
+++ b/src/lib/player.cc
@@ -132,6 +132,9 @@ Player::pass ()
        if (earliest_audio != TIME_MAX) {
                TimedAudioBuffers<DCPTime> tb = _audio_merger.pull (earliest_audio);
                Audio (tb.audio, tb.time);
+               /* This assumes that the audio_frames_to_time conversion is exact
+                  so that there are no accumulated errors caused by rounding.
+               */
                _audio_position += _film->audio_frames_to_time (tb.audio->frames ());
        }
 
@@ -141,16 +144,26 @@ Player::pass ()
        shared_ptr<DecodedAudio> da = dynamic_pointer_cast<DecodedAudio> (earliest_decoded);
        shared_ptr<DecodedSubtitle> ds = dynamic_pointer_cast<DecodedSubtitle> (earliest_decoded);
 
+       /* Will be set to false if we shouldn't consume the peeked DecodedThing */
+       bool consume = true;
+
+       /* This is the margin either side of _{video,audio}_position that we will accept
+          as a starting point for a frame consecutive to the previous.
+       */
+       DCPTime const margin = TIME_HZ / (2 * _film->video_frame_rate ());
+       
        if (dv && _video) {
-               DCPTime const half_frame = TIME_HZ / (2 * _film->video_frame_rate ());
 
                if (_just_did_inaccurate_seek) {
+
                        /* Just emit; no subtlety */
                        emit_video (earliest_piece, dv);
-                       earliest_piece->decoder->get ();
-               } else if (earliest_time > (_video_position + half_frame)) {
+                       step_video_position (dv);
+                       
+               } else if (dv->dcp_time - _video_position > margin) {
+
+                       /* Too far ahead */
 
-                       /* See if we're inside some video content */
                        list<shared_ptr<Piece> >::iterator i = _pieces.begin();
                        while (i != _pieces.end() && ((*i)->content->position() >= _video_position || _video_position >= (*i)->content->end())) {
                                ++i;
@@ -160,39 +173,47 @@ Player::pass ()
                                /* We're outside all video content */
                                emit_black ();
                        } else {
+                               /* We're inside some video; repeat the frame */
                                _last_incoming_video.video->dcp_time = _video_position;
                                emit_video (_last_incoming_video.weak_piece, _last_incoming_video.video);
+                               step_video_position (_last_incoming_video.video);
                        }
 
-               } else {
-
-                       if (
-                               dv->dcp_time >= _video_position &&
-                               !earliest_piece->content->trimmed (dv->dcp_time - earliest_piece->content->position ())
-                               ) {
+                       consume = false;
 
-                               emit_video (earliest_piece, dv);
-                       }
-               
-                       earliest_piece->decoder->get ();
+               } else if (abs (dv->dcp_time - _video_position) < margin) {
+                       /* We're ok */
+                       emit_video (earliest_piece, dv);
+                       step_video_position (dv);
+               } else {
+                       /* Too far behind: skip */
                }
 
+               _just_did_inaccurate_seek = false;
+
        } else if (da && _audio) {
-               if (!_just_did_inaccurate_seek && earliest_time > _audio_position) {
-                       emit_silence (earliest_time - _audio_position);
-               } else {
+
+               if (da->dcp_time - _audio_position > margin) {
+                       /* Too far ahead */
+                       emit_silence (da->dcp_time - _audio_position);
+                       consume = false;
+               } else if (abs (da->dcp_time - _audio_position) < margin) {
+                       /* We're ok */
                        emit_audio (earliest_piece, da);
-                       earliest_piece->decoder->get ();
+               } else {
+                       /* Too far behind: skip */
                }
+               
        } else if (ds && _video) {
                _in_subtitle.piece = earliest_piece;
                _in_subtitle.subtitle = ds;
                update_subtitle ();
-               earliest_piece->decoder->get ();
        }
 
-       _just_did_inaccurate_seek = false;
-
+       if (consume) {
+               earliest_piece->decoder->consume ();
+       }                       
+       
        return false;
 }
 
@@ -238,7 +259,7 @@ Player::emit_video (weak_ptr<Piece> weak_piece, shared_ptr<DecodedVideo> video)
 
                Position<int> const container_offset (
                        (_video_container_size.width - image_size.width) / 2,
-                       (_video_container_size.height - image_size.width) / 2
+                       (_video_container_size.height - image_size.height) / 2
                        );
 
                pi->set_subtitle (_out_subtitle.image, _out_subtitle.position + container_offset);
@@ -251,10 +272,17 @@ Player::emit_video (weak_ptr<Piece> weak_piece, shared_ptr<DecodedVideo> video)
        Video (pi, video->eyes, content->colour_conversion(), video->same, video->dcp_time);
        
        _last_emit_was_black = false;
+}
 
+void
+Player::step_video_position (shared_ptr<DecodedVideo> video)
+{
        /* This is a bit of a hack; don't update _video_position if EYES_RIGHT is on its way */
        if (video->eyes != EYES_LEFT) {
-               _video_position = rint (video->dcp_time + TIME_HZ / _film->video_frame_rate());
+               /* This assumes that the video_frames_to_time conversion is exact
+                  so that there are no accumulated errors caused by rounding.
+               */
+               _video_position += _film->video_frames_to_time (1);
        }
 }