Reversible YV12->YUY2->YV12

[vampiredom]

Hi all --

I know it's probably old-hat to most, but I am a big fan of the GrapeSmoother plugin: It's very fast, minimally destructive and seems to be ideal for already "mostly clean" material, like HDV or AVCHD footage.

Unfortunately, it only works in YUY2. I think I've found a way to convert YV12->YUY2->YV12 without the goofy sort of resampling that takes place with the conventional method, which seems to be especially troublesome for interlaced sources:

function GrapeSmootherYV12(clip c, int "strength") {
	strength=Default(Strength, 0)
	c

	wasYV12 = isYV12(c)

	SeparateFields()
	y  = ConvertToYUY2()
	uv = PointResize(width, height*2)
	u  = uv.UtoY().ConvertToYUY2()
	v  = uv.VtoY().ConvertToYUY2()

	(wasYV12)      ? YToUV(u,v,y).Weave().ConvertToYUY2(interlaced=true) : c
	(strength > 0) ? GrapeSmoother(strength)                             : last
	(wasYV12)      ? ConvertToYV12(interlaced=true)                      : last

}

Is there a better or faster way to do this? It is a bit slower than simply ConvertToYUY2().GrapeSmoother().ConvertToYV12() ... but the chroma integrity seems much better when done my way.

Or perhaps I'm totally wrong about my enitre approach? Advice would be appreciated