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NTCT · 21st February 2012, 07:12

I'm also a fan of averaging multiple captures. And yes, there is no realistic way to avoid manual alignment of the captures as of right now. What I want to point out is that VirtualDub actually does everything properly on its side. And VirtualDub is not the only source of frame drops/duplicates in the entire setup. VirtualDub does exactly what you tell it to do: capture frames at a certain rate, which is based on the clock rate of your PC. The trouble is that your VCR, TBC and PC all have slightly different clock rates. If the TBC doesn't get a new frame in time from your VCR, it will duplicate the frame. Or it will drop one if the frames come too close to each other. The main trouble is not VirtualDub itself. The main trouble is that you're trying to capture the data stream at a fixed frame rate. And your data stream, unfortunately, doesn't really come at a fixed frame rate. So, yes, it is best to use the average framerate of the actual video stream in the capture settings of VirtualDub. And still, this doesn't guarantee perfect frame accuracy, unfortunately.

21st February 2012, 07:12	#8 \| Link
NTCT Registered User Join Date: Jun 2011 Posts: 3	I'm also a fan of averaging multiple captures. And yes, there is no realistic way to avoid manual alignment of the captures as of right now. What I want to point out is that VirtualDub actually does everything properly on its side. And VirtualDub is not the only source of frame drops/duplicates in the entire setup. VirtualDub does exactly what you tell it to do: capture frames at a certain rate, which is based on the clock rate of your PC. The trouble is that your VCR, TBC and PC all have slightly different clock rates. If the TBC doesn't get a new frame in time from your VCR, it will duplicate the frame. Or it will drop one if the frames come too close to each other. The main trouble is not VirtualDub itself. The main trouble is that you're trying to capture the data stream at a fixed frame rate. And your data stream, unfortunately, doesn't really come at a fixed frame rate. So, yes, it is best to use the average framerate of the actual video stream in the capture settings of VirtualDub. And still, this doesn't guarantee perfect frame accuracy, unfortunately.