function negate($image)

if(function_exists('imagefilter'))

return imagefilter($image, IMG_FILTER_NEGATE);

for($x = 0; $x < imagesx($image); ++$x)

for($y = 0; $y < imagesy($image); ++$y)

$index = imagecolorat($image, $x, $y);

$rgb = imagecolorsforindex($index);

$color = imagecolorallocate($image, 255 - $rgb['red'], 255 - $rgb['green'], 255 - $rgb['blue']);

imagesetpixel($im, $x, $y, $color);

return(true);

$image = imagecreatefromjpeg('image1.jpg');

if($image && negate($image))

echo 'Image successfully converted to negative colors.';

imagejpeg($image, 'image1.jpg', 100);

imagedestroy($image);

echo 'Negative color conversion failed.';

After running the program you will get the following output

Related Tags for PHP GD image negative Color: