header('Content-type: image/jpeg');
// The file you are resizing
$file = './images/logo.jpg';

//This will set our output to 45% of the original size
$size = 0.45;

// This sets it to a .jpg, but you can change this to png or gif


// Setting the resize parameters
list($width, $height) = getimagesize($file);
$modwidth = $width * $size;
$modheight = $height * $size;

// Creating the Canvas
$tn= imagecreatetruecolor($modwidth, $modheight);
$source = imagecreatefromjpeg($file);

// Resizing our image to fit the canvas
imagecopyresized($tn, $source, 0, 0, 0, 0, $modwidth, $modheight, $width, $height);

// Outputs a jpg image, you could change this to gif or png if needed
imagejpeg($tn);
?>