Remove Image background with php and save transparent png

Question

I want to remove the white background of any image uploaded on the site working on PHP platform. The uploading function is done but messed up with this functionality.

Answer 1

The function from @geoffs3310 should be the accepted answer here, but note, that the png saved does not contain an alpha channel.

To remove the background and save the new png as a transparent png with alpha the following code works

$_filename='/home/files/IMAGE.png';
$_backgroundColour='0,0,0';
$_img = imagecreatefrompng($_filename);
$_backgroundColours = explode(',', $_backgroundColour);
$_removeColour = imagecolorallocate($_img, (int)$_backgroundColours[0], (int)$_backgroundColours[1], (int)$_backgroundColours[2]);
imagecolortransparent($_img, $_removeColour);
imagesavealpha($_img, true);
$_transColor = imagecolorallocatealpha($_img, 0, 0, 0, 127);
imagefill($_img, 0, 0, $_transColor);
imagepng($_img, $_filename);