dynamic image creation

[Anon]

I spoke with my administrator and he said the gif format is no longer supported because a company bought the format and they don't want to pay royalties. So they switched to the png format. So how do you tell the brower you are using the png format would it be like this?

<?php

Header( "Content-type: image/png");

?>

and then start creating the image. Is there anything else that is different for this standard? All the tutorials are for gif but gif is not supported by my host.

thanks