Php GD Library PNG display issue - php

Question

I've got a GD Library upload script which processing and resizes images. After uploading PNGs are getting rendering as a different image, some stock-looking image, on the browser side, yet when opened on disk they are correct. I've re-saved the affected pngs via photoshop and uploaded directly, this fixes the display issue, but when i upload that image via the script the display issue returns, thus the script encoding seems to cause issue with the browser display, but why i know not.
Hosting environment is Hetzner Server.
Upload Sample:
//resize images
protected function resize($img, $w, $h, $newfilename) {
//Check if GD extension is loaded
if (!extension_loaded('gd') && !extension_loaded('gd2')) {
trigger_error("GD is not loaded", E_USER_WARNING);
return false;
}
//Get Image size info
$imgInfo = getimagesize($img);
switch ($imgInfo[2]) {
case 1: $im = imagecreatefromgif($img); break;
case 2: $im = imagecreatefromjpeg($img); break;
case 3: $im = imagecreatefrompng($img); break;
default: trigger_error('Unsupported filetype!', E_USER_WARNING); break;
}
//If image dimension is smaller, do not resize
if ($imgInfo[0] <= $w && $imgInfo[1] <= $h) {
$nHeight = $imgInfo[1];
$nWidth = $imgInfo[0];
}
else{
// yeah, resize it, but keep it proportional
if ($w/$imgInfo[0] > $h/$imgInfo[1]) {
$nWidth = $imgInfo[0]*($h/$imgInfo[1]);
$nHeight = $h;
}
else{
$nWidth = $w;
$nHeight = $imgInfo[1]*($w/$imgInfo[0]);
}
}
$nWidth = round($nWidth);
$nHeight = round($nHeight);
$newImg = imagecreatetruecolor($nWidth, $nHeight);
/* Check if this image is PNG or GIF, then set if Transparent*/
if(($imgInfo[2] == 1) OR ($imgInfo[2]==3)){
imagealphablending($newImg, false);
imagesavealpha($newImg,true);
$transparent = imagecolorallocatealpha($newImg, 255, 255, 255, 127);
imagefilledrectangle($newImg, 0, 0, $nWidth, $nHeight, $transparent);
}
imagecopyresampled($newImg, $im, 0, 0, 0, 0, $nWidth, $nHeight, $imgInfo[0], $imgInfo[1]);
//Generate the file, and rename it to $newfilename
switch ($imgInfo[2]) {
case 1: imagegif($newImg,$newfilename); break;
case 2: imagejpeg($newImg,$newfilename,100); break;
case 3: imagepng($newImg,$newfilename,0); break;
default: trigger_error('Failed resize image!', E_USER_WARNING); break;
}
return $newfilename;
}
Can anyone give me some insight into this. Will provide more info if necessary. Ty
EDIT:
Browser Display
Disk Display
I have no clue where that image is coming from, it's on multiple uploads, when browsing the full path to the image on the browser the same image comes up so it's not a pathing issue.