Fix seeking with 3D alternate-frame sources.

diff --git a/ChangeLog b/ChangeLog
index cd47c1656fb773bff7d2bb0766ca548cb701f120..eae22c2a3f6b0789804e15ac95beeb213b3db3d2 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-24  Carl Hetherington  <cth@carlh.net>
+
+       * Fix various problems with 3D alternate-frame
+       sources.
+
 2016-10-19  Carl Hetherington  <cth@carlh.net>
 
        * Version 2.9.37 released.

diff --git a/src/lib/video_decoder.cc b/src/lib/video_decoder.cc
index 8c1b27653199716288b69e506c8ce84a08204c67..0d7cbfe2e3c745cdfd45ebc1156f0bce924f8308 100644 (file)
--- a/src/lib/video_decoder.cc
+++ b/src/lib/video_decoder.cc
@@ -87,7 +87,15 @@ VideoDecoder::get (Frame frame, bool accurate)
        _log->log (String::compose ("VD has request for %1", frame), LogEntry::TYPE_DEBUG_DECODE);
 
        if (_decoded.empty() || frame < _decoded.front().frame.index() || frame > (_decoded.back().frame.index() + 1)) {
-               _parent->seek (ContentTime::from_frames (frame, _content->active_video_frame_rate()), accurate);
+               Frame seek_frame = frame;
+               if (_content->video->frame_type() == VIDEO_FRAME_TYPE_3D_ALTERNATE) {
+                       /* 3D alternate is a special case as the frame index in the content is not the same
+                          as the frame index we are talking about here.
+                       */
+                       seek_frame *= 2;
+               }
+               _log->log (String::compose ("VD seeks to %1", seek_frame), LogEntry::TYPE_DEBUG_DECODE);
+               _parent->seek (ContentTime::from_frames (seek_frame, _content->active_video_frame_rate()), accurate);
        }
 
        /* Work out the number of frames that we should return; we
@@ -250,7 +258,15 @@ VideoDecoder::fill_both_eyes (VideoFrame from, VideoFrame to)
        }
 }
 
-/** Called by decoder classes when they have a video frame ready */
+/** Called by decoder classes when they have a video frame ready.
+ *  @param frame Frame index within the content; this does not take into account 3D
+ *  so for 3D_ALTERNATE this value goes:
+ *     0: frame 0 left
+ *     1: frame 0 right
+ *     2: frame 1 left
+ *     3: frame 1 right
+ *  and so on.
+ */
 void
 VideoDecoder::give (shared_ptr<const ImageProxy> image, Frame frame)
 {