What is PhpDig?
PhpDig is a PHP MySQL based
Web Spider & Search Engine.
imagecolorset — Replaces one color with another
bool imagecolorset(image, color, red,
int image: Image
int color: Color to
int red: Red component of
int green: Green component
of new color
int blue: Blue component of
TRUE on success; FALSE on error
Changes one color already in an image to a new specified
color. Useful for replacing a block of color in an image
without having to do any possibly complex redrawing
operations. In the following example, the closest blue is
found in the image using imagecolorclosest() and then
replaced with green. This demonstrates how a color
doesn't even need to be known exactly to be replaced.
Example 400. Replace blue
$im = imagecreate(200, 200);
$red = imagecolorallocate($im, 255, 0, 0);
$offblue = imagecolorallocate($im, 90, 90, 200);
imagefill($im, 0, 0, $red);
imagefilledrectangle($im, 10, 10, 40, 40, $offblue);
// above could come from an uploaded image
// find a blue in the image
$newblue = imagecolorclosest($im, 0, 0, 255);
// change it to green
imagecolorset($im, $newblue, 0, 255, 0);
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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