transparency problem with gd

[bobinindia]

I have this script that merges two images.

The really.png was created using a transparent white background.

That  means that any pixel with 255,255,255 becomes transparent. I wanted to limit it to the edges of the image. I think i am hopeful.

When merging in the code below holes apppear where there is were white pixels in really.png.

Any way around this?

 

<?php
$image = imagecreatefromjpeg($coin_url['template_url']);
$insert = imagecreatefrompng("really.png");
$image = image_overlap($image, $insert);


function image_overlap($background, $foreground){
   $insertWidth = imagesx($foreground);
   $insertHeight = imagesy($foreground);
   $imageWidth = imagesx($background);
   $imageHeight = imagesy($background);
   $halfx = ($imageWidth-$insertWidth)/2;
    $halfy = ($imageHeight-$insertHeight)/2;

   $overlapX = $imageWidth-$insertWidth-$halfx;
   $overlapY = $imageHeight-$insertHeight-$halfy;
imagecolortransparent($foreground,imagecolorat($foreground,0,0));
imagecopymerge($background,$foreground,$overlapX,$overlapY,0,0,$insertWidth,$insertHeight,100);
return $background;
    }
    imagejpeg($image, 'output.jpg');
?>