PHP upscale an image?

Question

I am new to php and trying to learn about image upscaling. can you please show me how can I upscale an image to a certain size? For example, I would like to re-size the following image while keeping the aspect ratio. If this can be done, can you please show me with an example

Answer 1

$source_image = imagecreatefromjpeg("osaka.jpg");
$source_imagex = imagesx($source_image);
$source_imagey = imagesy($source_image);
$dest_imagex = 300;
$dest_imagey = 200;
$dest_image = imagecreatetruecolor($dest_imagex, $dest_imagey);

Poor quality, but fast:

imagecopyresized($dest_image, $source_image, 0, 0, 0, 0, 
            $dest_imagex, $dest_imagey, $source_imagex, $source_imagey);

Best quality, but slow:

imagecopyresampled($dest_image, $source_image, 0, 0, 0, 0, 
            $dest_imagex, $dest_imagey, $source_imagex, $source_imagey);