[Image-SIG] RMS difference patch

[Fredrik Lundh]

Noah.org wrote:

> I have a patch that adds an RMS Difference method to the PIL.
> Let me know if there is any interest in this. I originally wrote this to
> help implement a video stabilization filter. You could also use
> this to quantify how much a lossy compression algorithm distorts
> an image relative to some other compression algorithm. I thought
> others might find RMS Difference useful.
> 
>     http://www.noah.org/wiki/PIL_patches
> 
> This is a patch against the Python Imaging Library Imaging-1.1.6.
> This adds the method ImageChops.difference_rms(im1, im2) which
> returns a float of the RMS difference between the two given
> images, im1 and im2.

isn't this equivalent to

     ImageStat.Stat(ImageChops.difference(i, im)).rms

?

(I'm busy with other stuff, so I might be missing something here).

</F>