well, just as usual, I didn't make my idea clear. I know very well, what an avisynth script does, that's why I'm asking for a (scriptable) filter to do the output. i am trying to do image quality measure just like you did, warpenterprises with your compare()-script. i don't want to do that with PSNR (well, I consider using that too, as you get a big bunch of values with your script), but with a program called DCTune, as described in the following threads :
http://forum.doom9.org/showthread.php?threadid=34034
http://forum.doom9.org/showthread.ph...0&pagenumber=4
DCTune computes a perceptual error, which is supposedly better to evaluate picture (video) quality than PSNR (I'm no expert there...)
Therefore you need 2 pictures, the original and the decoded picture to compare, both needed as ppm file. Until now, Im doing this by jumping with VD to the frame number of interest, copying it to clipboard, pasting it in GIMP, saving it as BMP and converting it to PPM with Slowview. Doing that on a lot of pictures (to get a better statistic) is really painful... thus my question.
But I'll definetly try your script as well, warp !
cheers