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Re: Supported File Formats to RubThrough

From: Tony Cook (
Date: Mon 04 Feb 2008 - 05:22:21 GMT

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    On Sun, Feb 03, 2008 at 08:32:26PM -0800, Greg Krieser wrote:

    > What file formats are supported for the RubThrough feature in
    > Imager? If used .tga in the past with success. However, I am
    > attempting to create another .tga but the Rubthrough is not working.
    > What "tricks" are needed to save .tga properly (from PhotoShop)? What
    > other formats are supported? Attempted .png and .gif with no success.

    Hi Greg,

    The problem you're seeing isn't the file format so much as the type of

    Imager will only rubthrough from a source image with an alpha channel,
    so if you TGA image is a straight RGB image with no transparency
    channel then rubthrough() won't work with it.

    Imager also won't accept using rubthrough from a RGBA image into a
    greyscale image.

    If you think your image does have an alpha channel, please send me a
    sample that isn't working as you expect.

    To work around these you need to either use the paste() method
    instead, or convert the target or source image to match the
    RGB/greyscale model of the other image.

    If your target image also has an alpha channel you should use add an
    alpha channel to the source before calling paste() since current
    releases of Imager won't synthesize one.

    The next release of Imager will fix a few problems with paste() and