GD! Converting a png image to jpeg and making the alpha by default white and not black

Question

I tried something like this but it just makes the background of the image white, not necessarily the alpha of the image. I wanted to just upload everything as jpg's so if i could somehow "flatten" a png image with some transparently to default it to just be white so i can use it as a jpg instead. Appreciate any help. Thanks.

$old = imagecreatefrompng($upload); $background = imagecolorallocate($old,255,255,255); imagefill($old, 0, 0, $background); imagealphablending($old, false); imagesavealpha($old, true);

Answer 1

<?php $input_file = "test.png"; $output_file = "test.jpg";  $input = imagecreatefrompng($input_file); $width = imagesx($input); $height = imagesy($input); $output = imagecreatetruecolor($width, $height); $white = imagecolorallocate($output,  255, 255, 255); imagefilledrectangle($output, 0, 0, $width, $height, $white); imagecopy($output, $input, 0, 0, 0, 0, $width, $height); imagejpeg($output, $output_file);