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help > Issue with backcolor command.
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Dec 10, 2021 10:12 AM | Matt Wall - Imanova Ltd.
Issue with backcolor command.
Hi everyone,
I'm having an issue with setting the background color. No matter what I set it to, when I save out bitmaps (either manually, or in a script) I get a dark-grey/black background. Have tried setting the background color through the GUI and using the gl.backcolor(x,y,z) command in a script. Am I doing something wrong?
Example image attached.
Many thanks,
Matt.
I'm having an issue with setting the background color. No matter what I set it to, when I save out bitmaps (either manually, or in a script) I get a dark-grey/black background. Have tried setting the background color through the GUI and using the gl.backcolor(x,y,z) command in a script. Am I doing something wrong?
Example image attached.
Many thanks,
Matt.
Dec 10, 2021 12:12 PM | Chris Rorden
RE: Issue with backcolor command.
Matt,
This is a feature, not a limitation of Surfice (and MRIcroGL). You can save bitmaps as either 32-bit RGBA where the background is transparent or as opaque 24-bit RGB with a fixed background color. The behavior is influenced by the Preference "Background transparent in bitmaps".
Due to partial-volume effects, the pixels at the edge of the brain will be a mixture of background and surface colors. This means that for opaque bitmaps the edge pixel color is a mixture of background color and surface color. This will be an issue if you use a tool like photoshop to superimpose images or change their background color. On the other hand, while transparent images require more disk space, they will nicely feather the edge color with any other colors.
This is a feature, not a limitation of Surfice (and MRIcroGL). You can save bitmaps as either 32-bit RGBA where the background is transparent or as opaque 24-bit RGB with a fixed background color. The behavior is influenced by the Preference "Background transparent in bitmaps".
Due to partial-volume effects, the pixels at the edge of the brain will be a mixture of background and surface colors. This means that for opaque bitmaps the edge pixel color is a mixture of background color and surface color. This will be an issue if you use a tool like photoshop to superimpose images or change their background color. On the other hand, while transparent images require more disk space, they will nicely feather the edge color with any other colors.