Code help please

I have tried changing the RGB colour solution shown in other posts.............

$background = imagecolorallocate($this->image, 255, 255, 255);
}

I changed this in system/library and cleared the image/cache/ data, but my images still have the white background. Is there something I have missed?

Thanks

what color you want for images background ?

Colour is 244,255,255. But as I say changing the code to that doesn't do anything!