Image.Channel method

[LiloLilo]

Hi, I found out that Image.channel(...) (Magick++) can be used to extract a single image channel. The class description I found is: "Extract channel from image. Use this option to extract a particular channel from the image"

What does it mean as channel function returns void? I'd like to pass a single channel to a function, it can be done?

Thank you all.

[anthony]

That probably means the channel did not exist. This can only happen for black and matte/alpha channels.