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TransparencyThe Transparency field can be used to specify a transparent color in the input image. This field only applies to .BMP files, since .GIF, .JPG, and .PNG files encode transparency information internal to the input file. In all cases, the transparent color will be saved as index 255 in the output PegBitmap, since index 255 is always interpreted as transparent by the PegScreen bitmap functions. Transparency forces the output PegBitmap structure to use 8-bpp encoding, since the default transparent color value is 255. This is true even if the source image contains only 2, 4, or 16 colors. If the source image is encoded using less than 8 bits-per-pixel, Image Convert will expand the image to 8 bits-per-pixel format when transparency is enabled. .BMP files do not inherently support transparency. To use image transparency, the source image(s) must be created such that all areas that should be displayed transparently are painted with an otherwise unused color. You must then inform Image Convert which color should be interpreted as transparent. There are two methods of specifying the transparent color: Specify RGB Value: If the source images are 24-bpp (true-color) images, you must specify an actual RGB value to use as the transparent color. If you select the 'RGB' button, you should enter the Red, Green, and Blue values in the string fields which are displayed. You can determine the correct values through examination with a paint program. Use Upper-Left Color: When this method is selected, Image Convert will assume that the upper left corner pixel is in the transparent color. This method can only be used with 16 and 256 color input images.
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