Question: Output where every other frame is the source frame

[OpenSourceAnarchist]

I'm trying to output a motion interpolated video where every other frame is the original frame.

My current method works fine, which is to return Interleave(C, SelectOdd(Flow)) where C is the input clip and Flow is the MFlowFps function. I simply use C.FrameRateNumerator * 2 for the numerator in MFlowFps and C.FrameRateDenominator (unchanged) for the denominator. Obviously, this mean 2x as many new frames than necessary are created since I am only using half the frames created by the MFlowFps function.

According to this post, mvtools2 automatically uses source frames in the Flow output "when you have integer framerate multiples," but I am not sure if this is true as I can't find this behavior in the documentation.

If anyone can help me achieve a more efficient method (creating only the necessary interpolated frames), I would really appreciate it!