+ if (ignore ()) {
+ return;
+ }
+
+ auto const afr = _content->active_video_frame_rate(film);
+ auto const vft = _content->video->frame_type();
+
+ /* Do some heuristics to try and spot the case where the user sets content to 3D
+ * when it is not. We try to tell this by looking at the differences in time between
+ * the first few frames. Real 3D content should have two frames for each timestamp.
+ */
+ if (_frame_interval_checker) {
+ _frame_interval_checker->feed(time, afr);
+ if (_frame_interval_checker->guess() == FrameIntervalChecker::PROBABLY_NOT_3D && vft == VideoFrameType::THREE_D) {
+ boost::throw_exception (
+ DecodeError(
+ String::compose(
+ _("The content file %1 is set as 3D but does not appear to contain 3D images. Please set it to 2D. "
+ "You can still make a 3D DCP from this content by ticking the 3D option in the DCP video tab."),
+ _content->path(0)
+ )
+ )
+ );
+ }
+
+ if (_frame_interval_checker->guess() != FrameIntervalChecker::AGAIN) {
+ _frame_interval_checker.reset ();
+ }
+ }
+
+ switch (vft) {
+ case VideoFrameType::TWO_D:
+ Data(ContentVideo(image, time, Eyes::BOTH, Part::WHOLE));
+ break;
+ case VideoFrameType::THREE_D:
+ {
+ auto eyes = Eyes::LEFT;
+ auto j2k = dynamic_pointer_cast<const J2KImageProxy>(image);
+ if (j2k && j2k->eye()) {
+ eyes = *j2k->eye() == dcp::Eye::LEFT ? Eyes::LEFT : Eyes::RIGHT;
+ }
+
+ Data(ContentVideo(image, time, eyes, Part::WHOLE));
+ break;
+ }
+ case VideoFrameType::THREE_D_ALTERNATE:
+ {
+ Eyes eyes;
+ if (_last_emitted_eyes) {
+ eyes = _last_emitted_eyes.get() == Eyes::LEFT ? Eyes::RIGHT : Eyes::LEFT;
+ } else {
+ /* We don't know what eye this frame is, so just guess */
+ auto frame = time.frames_round(_content->video_frame_rate().get_value_or(24));
+ eyes = (frame % 2) ? Eyes::RIGHT : Eyes::LEFT;
+ }
+ Data(ContentVideo(image, time, eyes, Part::WHOLE));
+ _last_emitted_eyes = eyes;
+ break;
+ }
+ case VideoFrameType::THREE_D_LEFT_RIGHT:
+ Data(ContentVideo(image, time, Eyes::LEFT, Part::LEFT_HALF));
+ Data(ContentVideo(image, time, Eyes::RIGHT, Part::RIGHT_HALF));
+ break;
+ case VideoFrameType::THREE_D_TOP_BOTTOM:
+ Data(ContentVideo(image, time, Eyes::LEFT, Part::TOP_HALF));
+ Data(ContentVideo(image, time, Eyes::RIGHT, Part::BOTTOM_HALF));
+ break;
+ case VideoFrameType::THREE_D_LEFT:
+ Data(ContentVideo(image, time, Eyes::LEFT, Part::WHOLE));
+ break;
+ case VideoFrameType::THREE_D_RIGHT:
+ Data(ContentVideo(image, time, Eyes::RIGHT, Part::WHOLE));
+ break;
+ default:
+ DCPOMATIC_ASSERT (false);
+ }
+
+ _position = time;