Increase the video picture queue size to 24

examples/alffplay.cpp

@@ -120,7 +120,7 @@ LPALEVENTCALLBACKSOFT alEventCallbackSOFT;
 const seconds AVNoSyncThreshold{10};
 
 const milliseconds VideoSyncThreshold{10};
-#define VIDEO_PICTURE_QUEUE_SIZE 16
+#define VIDEO_PICTURE_QUEUE_SIZE 24
 
 const seconds_d64 AudioSyncThreshold{0.03};
 const milliseconds AudioSampleCorrectionMax{50};