Um, not at all ... According to the RFC for PNG images, the alpha channel is defined for image transparency where values within this channel define the level of transparency - An alpha value of zero represents full transparency whereas a value of (2^bitdepth)-1 represents a fully opaque pixel. Intermediatary values indicate partial transparency such that composite images can be defined. Alternatively, PNG images can also have transparency defined via tRNS where the image can make use of a single palette colour as the transparency for the image in place of the use of the full alpha channel.

 

perl -e 's&&rob@cowsnet.com.au&&&split/[@.]/&&s&.com.&_&&&print'

In reply to Re: Re: Tk::Photo and GIFs - is a pixel transparent or black? by rob_au
in thread Tk::Photo and GIFs - is a pixel transparent or black? by crazyinsomniac

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