Fix bug that skips the first source frame when creating output frames

CrendKing · Dec 22, 2020 · c451fe3 · c451fe3
1 parent 7c5852a
commit c451fe3
Showing 1 changed file with 12 additions and 4 deletions.
diff --git a/avisynth_filter/src/frame_handler.cpp b/avisynth_filter/src/frame_handler.cpp
@@ -58,9 +58,15 @@ auto FrameHandler::AddInputSample(IMediaSample *inSample) -> HRESULT {
         return VFW_E_SAMPLE_REJECTED;
     }
 
-    if (_nextOutputFrameStartTime == 0) {
+    if (_nextOutputFrameStartTime == -1) {
         _nextOutputFrameStartTime = srcFrameInfo.startTime;
     }
+    if (_frameRateCheckpointInputSampleStartTime == -1) {
+        _frameRateCheckpointInputSampleStartTime = srcFrameInfo.startTime;
+    }
+    if (_frameRateCheckpointOutputFrameStartTime == -1) {
+        _frameRateCheckpointOutputFrameStartTime = srcFrameInfo.startTime;
+    }
 
     RefreshInputFrameRates(srcFrameInfo);
 
@@ -294,12 +300,12 @@ auto FrameHandler::Reset() -> void {
     _nextSourceFrameNb = 0;
     _nextOutputFrameNb = 0;
     _nextDeliverFrameNb = 0;
-    _nextOutputFrameStartTime = 0;
+    _nextOutputFrameStartTime = -1;
 
     _frameRateCheckpointInputSampleNb = 0;
-    _frameRateCheckpointInputSampleStartTime = 0;
+    _frameRateCheckpointInputSampleStartTime = -1;
     _frameRateCheckpointOutputFrameNb = 0;
-    _frameRateCheckpointOutputFrameStartTime = 0;
+    _frameRateCheckpointOutputFrameStartTime = -1;
     _currentInputFrameRate = 0;
     _currentOutputFrameRate = 0;
 }
@@ -414,6 +420,8 @@ auto FrameHandler::GarbageCollect(int srcFrameNb) -> void {
 
     const size_t dbgPreSize = _sourceFrames.size();
 
+    // search for all previous zero-ref frames in case of some source frames are never used
+    // this could happen by plugins that decrease frame rate
     auto iter = _sourceFrames.begin();
     do {
         if (iter->first == srcFrameNb) {