Subtitle queue: Avoid blinking caused by small rounding error.

1 files changed, 7 insertions, 1 deletions

diff --git a/src/SubPic/SubPicQueueImpl.cpp b/src/SubPic/SubPicQueueImpl.cpp
index 0951988c9..75f1b5fac 100644
--- a/src/SubPic/SubPicQueueImpl.cpp
+++ b/src/SubPic/SubPicQueueImpl.cpp
@@ -579,8 +579,14 @@ DWORD CSubPicQueue::ThreadProc()
                         if (bIsAnimated) {

                             REFERENCE_TIME rtEndThis = std::min(rtCurrent + rtTimePerSubFrame, rtStopReal);

                             hr = RenderTo(pStatic, rtCurrent, rtEndThis, fps, bIsAnimated);

+                            // Set the segment start and stop timings

                             pStatic->SetSegmentStart(rtStart);

-                            pStatic->SetSegmentStop(rtStopReal);

+                            // The stop timing can be moved so that the duration from the current start time

+                            // of the subpic to the segment end is always at least one video frame long. This

+                            // avoids missing subtitle frame due to rounding errors in the timings.

+                            // At worst this can cause a segment to be displayed for one more frame than expected

+                            // but it's much less annoying than having the subtitle disappearing for one frame

+                            pStatic->SetSegmentStop(std::max(rtCurrent + rtTimePerFrame, rtStopReal));

                             rtCurrent = rtEndThis;

                         } else {

                             hr = RenderTo(pStatic, rtStart, rtStopReal, fps, bIsAnimated);