v7 %[distortion]

[snibgo]

On Windows, pre-built Q16 integer binaries.

v6.9.2-5 gives a correct result:

Code: Select all

%IM%convert rose: ( rose: -modulate 100,99,100 ) -metric RMSE -format "%[distortion]" -compare info:
0.00185604

v7.0.1-3 gives a wrong result:

Code: Select all

%IMG7%magick rose: ( rose: -modulate 100,99,100 ) -metric RMSE -format "%[distortion]" -compare info:
1.0003

(RMSE values should always be in the range 0.0 to 1.0, with 0.0 meaning perfect match and 1.0 meaning as far apart as they can get.)

v7 RMSE %[distortion] values are wrong. I haven't tested other metrics.

[magick]

We're using ImageMagick 7.0.1-4 (available tomorrow):

• -> convert rose: \( rose: -modulate 100,99,100 \) -metric RMSE -format "%[distortion]" -compare info:
  0.00185611

[snibgo]

Great, thanks.

[snibgo]

This is wrong in v7.0.2-5 on Windows 8.1. Below, correct results are from v6.9.5-3.


%IM%convert rose: rose: -metric RMSE -format "%%[distortion]" -compare info:
0 <-- correct

%IMG7%magick rose: rose: -metric RMSE -format "%%[distortion]" -compare info:
1 <-- wrong


%IM%convert rose: ( rose: -modulate 100,99,100 ) -metric RMSE -format "%%[distortion]" -compare info:
0.00185604 <-- correct

%IMG7%magick rose: ( rose: -modulate 100,99,100 ) -metric RMSE -format "%%[distortion]" -compare info:
0.999985 <-- wrong

[magick]

Thanks for the problem report. We can reproduce it and will have a patch to fix it in GIT master branch @ https://github.com/ImageMagick/ImageMagick later today. The patch will be available in the beta releases of ImageMagick @ http://www.imagemagick.org/download/beta/ by sometime tomorrow.