[magick-users] problem with compose=>'CopyOpacity'

[Günter Bachelier]

Hello,

why remains $mask after compose=>'CopyOpacity' unchanged?

$extraction_mask->Set(matte=>'false'); # $extraction_mask = white 
hexagon on black background
$mask->Composite(image=>$extraction_mask, compose=>'CopyOpacity');
$mask->Set(page=>'0x0+0+0');

I tried also
$extraction_mask->Quantize(colors=>2, colorspace=>'Gray')
without success.


Guenter




Günter Bachelier schrieb:
> Hello,
>
> I want to extract specific hexagonal regions with freestanding
> structures from images (p3m1 tiles and patterns) like
>
> http://www.vi-anec.de/Trance-Art/IM-examples/p3m1_extraction/extraction_type_1.jpg 
>
> http://www.vi-anec.de/Trance-Art/IM-examples/p3m1_extraction/extraction_type_2.jpg 
>
>
> I have tried to make this by drawing an extraction mask
> (with matte=>'false') and use compose=>'CopyOpacity' but the image 
> remains unchanged after the operation.
> See PerlMagick code in
>
> http://www.vi-anec.de/Trance-Art/IM-examples/p3m1_extraction/Test_p3m1_extraction.PLX 
>
>
> I would appreciate any help because I need such an extraction
> method also for some other symmetry group tiles and patterns.
> Thank you very much!
>
>
> Guenter