1 files changed, 132 insertions, 14 deletions

diff --git a/src/lib/video_decoder.cc b/src/lib/video_decoder.cc
index 5867ac925..64c66ea55 100644
--- a/src/lib/video_decoder.cc
+++ b/src/lib/video_decoder.cc
@@ -19,46 +19,164 @@
 
 #include "video_decoder.h"
 #include "image.h"
+#include "image_proxy.h"
+#include "content_video.h"
 
 #include "i18n.h"
 
 using std::cout;
+using std::list;
+using std::max;
 using boost::shared_ptr;
+using boost::optional;
 
-VideoDecoder::VideoDecoder (shared_ptr<const Film> f, shared_ptr<const VideoContent> c)
-	: Decoder (f)
+VideoDecoder::VideoDecoder (shared_ptr<const VideoContent> c)
+#ifdef DCPOMATIC_DEBUG
+	: test_gaps (0)
 	, _video_content (c)
-	, _video_position (0)
+#else
+	: _video_content (c)
+#endif
+	, _same (false)
 {
 
 }
 
+list<ContentVideo>
+VideoDecoder::decoded_video (VideoFrame frame)
+{
+	list<ContentVideo> output;
+	
+	for (list<ContentVideo>::const_iterator i = _decoded_video.begin(); i != _decoded_video.end(); ++i) {
+		if (i->frame == frame) {
+			output.push_back (*i);
+		}
+	}
+
+	return output;
+}
+
+/** Get all frames which exist in the content at a given frame index.
+ *  @param frame Frame index.
+ *  @param accurate true to try hard to return frames at the precise time that was requested, otherwise frames nearby may be returned.
+ *  @return Frames; there may be none (if there is no video there), 1 for 2D or 2 for 3D.
+ */
+list<ContentVideo>
+VideoDecoder::get_video (VideoFrame frame, bool accurate)
+{
+	/* At this stage, if we have get_video()ed before, _decoded_video will contain the last frame that this
+	   method returned (and possibly a few more).  If the requested frame is not in _decoded_video and it is not the next
+	   one after the end of _decoded_video we need to seek.
+	*/
+	   
+	if (_decoded_video.empty() || frame < _decoded_video.front().frame || frame > (_decoded_video.back().frame + 1)) {
+		seek (ContentTime::from_frames (frame, _video_content->video_frame_rate()), accurate);
+	}
+
+	list<ContentVideo> dec;
+
+	/* Now enough pass() calls should either:
+	 *  (a) give us what we want, or
+	 *  (b) give us something after what we want, indicating that we will never get what we want, or
+	 *  (c) hit the end of the decoder.
+	 */
+	if (accurate) {
+		/* We are being accurate, so we want the right frame.
+		 * This could all be one statement but it's split up for clarity.
+		 */
+		while (true) {
+			if (!decoded_video(frame).empty ()) {
+				/* We got what we want */
+				break;
+			}
+
+			if (pass ()) {
+				/* The decoder has nothing more for us */
+				break;
+			}
+
+			if (!_decoded_video.empty() && _decoded_video.front().frame > frame) {
+				/* We're never going to get the frame we want.  Perhaps the caller is asking
+				 * for a video frame before the content's video starts (if its audio
+				 * begins before its video, for example).
+				 */
+				break;
+			}
+		}
+
+		dec = decoded_video (frame);
+	} else {
+		/* Any frame will do: use the first one that comes out of pass() */
+		while (_decoded_video.empty() && !pass ()) {}
+		if (!_decoded_video.empty ()) {
+			dec.push_back (_decoded_video.front ());
+		}
+	}
+
+	/* Clean up _decoded_video; keep the frame we are returning, but nothing before that */
+	while (!_decoded_video.empty() && _decoded_video.front().frame < dec.front().frame) {
+		_decoded_video.pop_front ();
+	}
+
+	return dec;
+}
+
+
+/** Called by subclasses when they have a video frame ready */
 void
-VideoDecoder::video (shared_ptr<const ImageProxy> image, bool same, VideoContent::Frame frame)
+VideoDecoder::video (shared_ptr<const ImageProxy> image, VideoFrame frame)
 {
+	/* We may receive the same frame index twice for 3D, and we need to know
+	   when that happens.
+	*/
+	_same = (!_decoded_video.empty() && frame == _decoded_video.back().frame);
+
+	/* Fill in gaps */
+	/* XXX: 3D */
+
+	while (!_decoded_video.empty () && (_decoded_video.back().frame + 1) < frame) {
+#ifdef DCPOMATIC_DEBUG
+		test_gaps++;
+#endif
+		_decoded_video.push_back (
+			ContentVideo (
+				_decoded_video.back().image,
+				_decoded_video.back().eyes,
+				_decoded_video.back().part,
+				_decoded_video.back().frame + 1
+				)
+			);
+	}
+	
 	switch (_video_content->video_frame_type ()) {
 	case VIDEO_FRAME_TYPE_2D:
-		Video (image, EYES_BOTH, PART_WHOLE, same, frame);
+		_decoded_video.push_back (ContentVideo (image, EYES_BOTH, PART_WHOLE, frame));
 		break;
 	case VIDEO_FRAME_TYPE_3D_ALTERNATE:
-		Video (image, (frame % 2) ? EYES_RIGHT : EYES_LEFT, PART_WHOLE, same, frame / 2);
+		_decoded_video.push_back (ContentVideo (image, _same ? EYES_RIGHT : EYES_LEFT, PART_WHOLE, frame));
 		break;
 	case VIDEO_FRAME_TYPE_3D_LEFT_RIGHT:
-		Video (image, EYES_LEFT, PART_LEFT_HALF, same, frame);
-		Video (image, EYES_RIGHT, PART_RIGHT_HALF, same, frame);
+		_decoded_video.push_back (ContentVideo (image, EYES_LEFT, PART_LEFT_HALF, frame));
+		_decoded_video.push_back (ContentVideo (image, EYES_RIGHT, PART_RIGHT_HALF, frame));
 		break;
 	case VIDEO_FRAME_TYPE_3D_TOP_BOTTOM:
-		Video (image, EYES_LEFT, PART_TOP_HALF, same, frame);
-		Video (image, EYES_RIGHT, PART_BOTTOM_HALF, same, frame);
+		_decoded_video.push_back (ContentVideo (image, EYES_LEFT, PART_TOP_HALF, frame));
+		_decoded_video.push_back (ContentVideo (image, EYES_RIGHT, PART_BOTTOM_HALF, frame));
 		break;
 	case VIDEO_FRAME_TYPE_3D_LEFT:
-		Video (image, EYES_LEFT, PART_WHOLE, same, frame);
+		_decoded_video.push_back (ContentVideo (image, EYES_LEFT, PART_WHOLE, frame));
 		break;
 	case VIDEO_FRAME_TYPE_3D_RIGHT:
-		Video (image, EYES_RIGHT, PART_WHOLE, same, frame);
+		_decoded_video.push_back (ContentVideo (image, EYES_RIGHT, PART_WHOLE, frame));
 		break;
+	default:
+		assert (false);
 	}
-	
-	_video_position = frame + 1;
+}
+
+void
+VideoDecoder::seek (ContentTime, bool)
+{
+	_decoded_video.clear ();
 }