possible bug compare -metric ncc IM 6.8.9.0 Q16 Mac OSX
Posted: 2014-05-05T12:08:31-07:00
The NCC metric should report 1 for a perfect match. If the images have an alpha channel, even if fully opaque in both, it fails.
This works fine
But this fails
But if the alpha channel is disabled, then it works again
This works fine
Code: Select all
compare -metric ncc rose: rose: null:
1.00031Code: Select all
convert rose: -alpha set rose1.png
compare -metric ncc rose1.png rose1.png null:
0.866294Code: Select all
compare -metric ncc -alpha off rose1.png rose1.png null:
1.00002