My wish is just to add a value between 1 and 100 to the compare function parameters. It represents the percentage of similitude of the images : in many cases images are not exactly the same but are ...
Are you using the compare pictures operation? This is already a supported paramter.
PixelTolerance
Lets you ignore a slight difference between the images. If the number of different pixels is less than or equal to PixelTolerance, then TestComplete considers the images to be identical. 0 is the default value. It means that no difference between the bitmaps, except for that set by the Transparent parameter, is ignored.