What to use instead of copy_opacity?

[druzhynin-oleksii]

There were copy_opacity as a composite operator in ImageMagic 6 https://github.com/emcconville/wand/blob/master/wand/image.py#L374

Is there a substitution in ImageMagic 7 among COMPOSITE_OPERATORS (https://github.com/emcconville/wand/blob/master/wand/image.py#L386C5-L386C24)?

[emcconville]

The opacity channel was replaced with alpha with ImageMagick 7. All the methods work the same as before -- however alpha is the inverse of opacity (e.g. 80% opacity == 20% alpha.)

From the Porting to ImageMagick Version 7 guide.

Alpha

We support alpha now, previously opacity. With alpha, a value of 0 means that the pixel does not have any coverage information and is transparent; i.e. there was no color contribution from any geometry because the geometry did not overlap this pixel. A value of QuantumRange means that the pixel is opaque because the geometry completely overlapped the pixel. As a consequence, in version 7, the PixelInfo structure member alpha has replaced the previous opacity member. Another consequence is the alpha part of an sRGB value in hexadecimal notation is now reversed (e.g. #0000 is fully transparent).

TL;DR

Use copy_alpha