16.9. Adding TransparencySpecifying the part of an image that should be transparent is as simple as picking the color to use as transparent and passing it into the imagecolortransparent( ) function. As the support for transparency in some browsers (notably with Internet Explorer and PNG transparency) is limited, this function is most useful when the transparent image is used as part of a larger image so that the transparency can be seen. $image = imagecreatetruecolor(400,400); $black = imagecolorallocate($image, 0, 0, 0); imagecolortransparent($image, $black); /// rest of picture here
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