[magick-users] How to specify transparent color in palletized PNG image?

[Jonnie Walker]

Hi ImageMagick users,

I was wondering on how to specify a transparent color for a PNG image that uses a palette. The options "transparent" and "transparent-color" do not work. They either create an alpha mask or nothing happens at all.

In the basic usage description the following is documented: 
"Transparency in such images are usually handled either by specifying a specific color as representing transparency (set using the "-transparent-color" meta-data setting) as in GIF format, or using a special profile for a specific number of colors in the color table in a PNG8 image. However only a single color transparency is implemented in IM bit image formats at this time."
So I assume that it is possible to specify at least one transparency color.

Thank you in advance for your help.

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