[magick-users] Luminance diff in magick tool

[Wei Guo]

Hi Fred,

Thanks a lot for help. I tried to convert both of them in Luminance space
and then do the compare. I got the result as below:

2909.9(0.0444022)

For square root RMSE .... (sq)root mean squared error -- IE:  sqrt(MSE), is
it too big? So I have to see those two images are different?

Best regards,

Wei

On 7/1/08, Fred Weinhaus <fmw at alink.net> wrote:
>
> see Rec709Luma in the table for colorspaces at
> http://www.imagemagick.org/script/command-line-options.php#colorspace
>
> also see the various compare metrics at
> http://www.imagemagick.org/Usage/compare/#statistics
>
> To compare just the luminance of two images you can do the following:
>
> convert image1.png -colorspace Rec709Luma image1_luma.png
> convert image2.png -colorspace Rec709Luma image2_luma.png
> compare -metric rmse  image1_luma.png  image2_luma.png null:
>
> You may be able to do it in one command line as:
>
> compare -metric rmse \( image1.png -colorspace Rec709Luma \) \(
> image2.png -colorspace Rec709Luma \) null:
>
>
>
>
>
>
>
>
>
> >Hi all,
> >
> >I am very new to this community. Now I am looking for a image comparison
> >tool which can provide threshold for luminance of images. I have some
> images
> >which are similar and only difference are luminance. Could compare handle
> >it? I played with several parameters but can not find the result.
> >
> >There are two images and I hope to tuning the parameter and compare can
> >ignore the difference of luminance.
> >
> >Best regards,
> >
> >Wei
> _______________________________________________
> Magick-users mailing list
> Magick-users at imagemagick.org
> http://studio.imagemagick.org/mailman/listinfo/magick-users
>