How to replace black background with white when resizing/converting PNG images with transparent backgrounds to JPEG.

Question

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

Answer 1

Try like this (not tested):

case "png":
  $file = imagecreatetruecolor($width, $height);
  $new = imagecreatefrompng($this->file_tempname);
  imagefilledrectangle ($file, 0, 0, $width, $height, imagecolorallocate($file, 0,0,0))

(predraw a white background on $file image)

Also, the for($i=0; $i<256; $i++) { imagecolorallocate($file, $i, $i, $i); } part looks strange.