by
DEANNA ROSE
This is the 'contrast' or 'complementary' graphic
This is the image you want to display
mask BLACK and white
mask WHITE and black
I have used the same mask for both examples...I negated the original for the difference
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First part of lesson- using a WHITE and black mask
Enter IM with display graphic
composite copyOpacity with WHITE and black mask/grav=center
You now have a png with transparent areas....output as png to show you what happens. Not necessary to output at this point but I wanted you to see what happened after the copyOpacity
See how the white part of the mask picked up the image of the girls face? The 'black' part is actually transparent
composite dstOver with contrast graphic/grav=center
The dstOver composite filled in all the transparent areas
finished
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Now, let's do it with the BLACK and white mask.
enter IM with contrast graphic
composite/copyOpacity with BLACK/white mask
output as png to show results only...this step is not necessary...for showing results only
See how the white part of the mask picked up the image of the contrast graphic with the copyOpacity composite, leaving the rest transparent, making a 'frame' to proceed
composite dstOver with display graphic
The dstOver composite filled in all the transparent areas
finished
The end result is the same.
The order of use of graphics is different, depending on whether your mask is primarily black or primarily white.