Re-fix the VFR fix in r3084 by restoring the old behavior (which was correct for the only existing providers at the time it was implemented, I think) under a special condition that only triggers for the AVS provider. This does not really actually fix any bugs; the new behavior wasn't any better (in fact it was probably incorrect in some cases) but at least this way doesn't have any of the regressions the new way might have introduced.

Originally committed to SVN as r3211.

aegisub/src/include/aegisub/video_provider.h

@@ -74,8 +74,9 @@ public:
 	// How many frames does this provider want Aegisub to cache? Set to 0 if it doesn't require caching.
 	virtual int GetDesiredCacheSize() { return 0; }
 
-	// For providers that are natively time-based (e.g. DirectShow)
-	virtual bool IsNativelyByFrames() { return true; }
+	// For "special" providers that don't deal well with VFR (i.e. Avisynth)
+	virtual bool NeedsVFRHack() { return false; };					// Returns true if provider needs special VFR treatment
+	virtual bool IsNativelyByFrames() { return true; };
 	virtual void OverrideFrameTimeList(Aegisub::IntArray list) {}	// Override the list with the provided one, for VFR handling
 };
 

aegisub/src/video_context.cpp

@@ -272,20 +272,22 @@ void VideoContext::SetVideo(const wxString &filename) {
 				keyFramesLoaded = false;
 			}
 			
-			bool isVfr = provider->IsVFR();
-			
 			// Set frame rate
 			fps = provider->GetFPS();
-			// if the source is vfr and the provider isn't frame-based (i.e. is dshow),
-			// we need to jump through some hoops to make VFR work properly.
-			if (!provider->IsNativelyByFrames() && isVfr) {
+			// does this provider need special vfr treatment?
+			if (provider->NeedsVFRHack()) {
+				// FIXME:
+				// Unfortunately, this hack does not actually work for the one
+				// provider that needs it (Avisynth). Go figure.
+				bool isVfr = provider->IsVFR();
+				if (!isVfr || provider->IsNativelyByFrames()) {
+					VFR_Input.SetCFR(fps);
+					if (VFR_Output.GetFrameRateType() != VFR) VFR_Output.SetCFR(fps);
+				}
+				else {
 					FrameRate temp = provider->GetTrueFrameRate();
 					provider->OverrideFrameTimeList(temp.GetFrameTimeList());
 				}
-			// source not VFR? set as CFR
-			else if (!isVfr) {
-				VFR_Input.SetCFR(fps);
-				if (VFR_Output.GetFrameRateType() != VFR) VFR_Output.SetCFR(fps);
 			}
 
 			// Gather video parameters

aegisub/src/video_provider_avs.h

@@ -89,6 +89,7 @@ public:
 
 	void OverrideFrameTimeList(wxArrayInt list);
 	bool IsNativelyByFrames() { return byFrame; }
+	bool NeedsVFRHack() { return true; }
 	Aegisub::String GetWarning();
 	Aegisub::String GetDecoderName() { return Aegisub::String(L"Avisynth/") + decoderName; }
 };

aegisub/src/video_provider_cache.cpp

@@ -167,6 +167,9 @@ void VideoProviderCache::OverrideFrameTimeList(Aegisub::IntArray list) {
 bool VideoProviderCache::IsNativelyByFrames() {
 	return master->IsNativelyByFrames();
 }
+bool VideoProviderCache::NeedsVFRHack() {
+	return master->NeedsVFRHack();
+}
 Aegisub::String VideoProviderCache::GetWarning() {
 	return master->GetWarning();
 }

aegisub/src/video_provider_cache.h

@@ -89,6 +89,7 @@ public:
 	virtual FrameRate GetTrueFrameRate();
 	virtual void OverrideFrameTimeList(Aegisub::IntArray list);	// Override the list with the provided one, for VFR handling
 	virtual bool IsNativelyByFrames();
+	virtual bool NeedsVFRHack();
 	virtual Aegisub::String GetWarning();
 	virtual Aegisub::String GetDecoderName();
 };

aegisub/src/video_provider_ffmpegsource.h

@@ -85,7 +85,6 @@ public:
 	bool IsVFR() { return true; };
 	FrameRate GetTrueFrameRate() { return Timecodes; };
 	Aegisub::String GetDecoderName() { return L"FFmpegSource"; }
-	bool IsNativelyByFrames() { return true; }
 	int GetDesiredCacheSize() { return 8; }
 };
 

aegisub/src/video_provider_yuv4mpeg.h

@@ -129,11 +129,10 @@ public:
 	int GetHeight();
 	double GetFPS();
 	bool AreKeyFramesLoaded() { return false; }
-	wxArrayInt GetKeyFrames() { return wxArrayInt(); };
+	wxArrayInt GetKeyFrames() { return wxArrayInt(); }
 	bool IsVFR() { return false; };
-	FrameRate GetTrueFrameRate() { return FrameRate(); };
+	FrameRate GetTrueFrameRate() { return FrameRate(); }
 	Aegisub::String GetDecoderName() { return L"YUV4MPEG"; }
-	bool IsNativelyByFrames() { return true; }
 	int GetDesiredCacheSize() { return 8; }
 };