"FancyResize" PHP script - destroys images - php

Question

I have a script from an old website called FancyResize, that resizes images to a new requested width and height. For some reason it now "destroys" images when used - not every time, but in many circumstances it makes a weird color overlay, changes pixels etc., so it is impossible to see what image it actually should have been. I guess it could have something to do with new PHP version etc., but I don't know, but I guess it have worked before.
So, my question is: can anybody see a mistake in this?
<?
$new_width = $_REQUEST[w];
$new_height = $_REQUEST[h];
$file = $_REQUEST[i];
$localpath = "WEBSITENAME";
$query = $_SERVER[QUERY_STRING];
$datafile = $_SERVER[DOCUMENT_ROOT].'/img/fronttemp/'.md5($query);
if (file_exists($datafile))
{
header("Content-type: image/jpeg");
die(file_get_contents($datafile));
}
if (substr($file, 0, strlen($localpath)) == $localpath)
{
$file = substr($file, strlen($localpath));
$file = $_SERVER[DOCUMENT_ROOT].$file;
}
else
{
$file = substr($query, strpos($query, "&i=")+3);
}
$image = imagecreatefromjpeg($file);
if (!$image)
{
$image =imagecreatefromgif($file);
$is_gif = true;
}
else $is_gif = false;
if (!$image) die("error reading gif/jpg $file");
$info = getimagesize($file) or die("error getting info");
$width = $info[0];
$height = $info[1];
$input_landscape = ($width/$height)>1;
$output_landscape = ($new_width/$new_height)>1;
function imageScaleToWidth($image, $new_height, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
$scale_height = ceil(($new_width/$width)*$height);
$scaledimage = imagecreatetruecolor($new_width, $scale_height);
$white = imagecolorallocate($scaledimage, 255, 255, 255);
imagecolortransparent($dest, $scaledimage);
imagecopyresampled($scaledimage, $image, 0,0,0,0, $new_width, $scale_height, $width, $height);
return $scaledimage;
}
function imageScaleToHeight($image, $new_height, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
$scale_width = ceil(($new_height/$height)*$width);
$scaledimage = imagecreatetruecolor($scale_width, $new_height);
$white = imagecolorallocate($scaledimage, 255, 255, 255);
imagecolortransparent($dest, $scaledimage);
imagecopyresampled($scaledimage, $image, 0,0,0,0, $scale_width, $new_height, $width, $height);
return $scaledimage;
}
function makeImageWideEnough($image, $new_height, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
if ($width < $new_width)
{
$scale_height = ceil(($new_width/$width)*$height);
$scaledimage = imagecreatetruecolor($new_width, $scale_height);
imagecopyresampled($scaledimage, $image, 0,0,0,0, $new_width, $scale_height, $width, $height);
return $scaledimage;
}
return $image;
}
function makeImageHighEnough($image, $new_height, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
if ($height < $new_height)
{
$scale_width = ceil(($new_height/$height)*$width);
$scaledimage = imagecreatetruecolor($scale_width, $new_height);
imagecopyresampled($scaledimage, $image, 0,0,0,0, $scale_width, $new_height, $width, $height);
return $scaledimage;
}
return $image;
}
function imageCrop($image, $new_height, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
$croppedimage = imagecreatetruecolor($new_width, $new_height);
$sx = ($width-$new_width)/4;
$sy = ($height-$new_height)/4;
imagecopy($croppedimage, $image, 0, 0, $sx, $sy, $new_width, $new_height);
return $croppedimage;
}
function scaleWidth($image, $new_width)
{
$width = imagesx($image);
$height = imagesy($image);
$ratio = $new_width / $width;
$sx = ceil($width*$ratio);
$sy = ceil($height*$ratio);
$scaledimage = imagecreatetruecolor($sx, $sy);
$white = imagecolorallocate($scaledimage, 255, 255, 255);
imagecolortransparent($dest, $scaledimage);
imagecopyresampled($scaledimage, $image, 0,0,0,0, $sx, $sy, $width, $height);
return $scaledimage;
}
$croppedimage = scaleWidth($image, $new_width);
if ($new_height < imagesy($croppedimage))
{
$croppedimage = imageCrop($croppedimage,$new_height,$new_width);
}
header("Content-type: image/jpeg");
imagejpeg($croppedimage, $datafile);
echo file_get_contents($datafile);
?>