PHP
(quick guide & example)
SOURCE & DESTINATION $src = "ORIGINAL.JPG"; $dest = "RESIZED.JPG";
ORIGINAL IMAGE DIMENSIONS $dim = getimagesize($src); $ow = $dim[0]; $oh = $dim[1];
RESIZE DIMENSIONS $resize = 0.8; $rw = ceil($ow * $resize); $rh = ceil($oh * $resize);
ORIGINAL IMAGE $o = imagecreatefromjpeg($src);
COPY & RESIZE $r = imagecreatefromjpeg($rw, $rh); imagecopyresampled( $r, $o, 0, 0, 0, 0, $rw, $rh, $ow, $oh );
RESIZE IMAGE $tx = 0; $ty = 0; $sx = 0; $sy = 0; imagecopyresampled($resized, $original, $tx, $ty, $sx, $sy, $rw, $rh, $ow, $oh);
SAVE RESIZED IMAGE imagejpeg($resized, "resized.jpg");