Would like to turn this into black and white.. can't figure out what to use from imagick..
$handle_data = file_get_contents('http://www.bungie.net/Stats/Reach/Nightmap.ashx'); //http://www.bungie.net/Stats/Halo3/Nightmap.ashx $img = new Imagick(); $img->readImageBlob($handle_data); $img->writeImage('nightmap/'.$time.'.gif');
Using Imagick::modulateImage could be a quick&dirty solution. Dirty because color theory is a rather complex field, and there can be done more to create grayscale images than just desaturating the image (like applying different weights to the single color channels).
bool Imagick::modulateImage (float $brightness , float $saturation , float $hue)
Given an image, keep
hue at 100%, while setting
saturation to 0%. There is an example at the bottom of the documentation page that does exactly that.
There's a much better (and just as simple) solution:
$im = $im->fxImage('intensity');
That applies a function to the image, where intensity is equal to
That formula is based on how our eyes are more sensitive to different colours, and as such the difference between that and a "flat" grayscale image really is night and day.
More details here: