I am using a script that lets users upload images. The script resizes and converts the images to JPEG.
The problem I have is when a PNG with transparency is uploaded
After Image true colour add the lines:
$file = imagecreatetruecolor($width, $height);
$background = imagecolorallocate($file, 0, 0, 0);
imagecolortransparent($file, $background);
imagealphablending($file, false);
imagesavealpha($file, true);
This will help in mailtaining alpha for all formats. Ping if u dont get answer.