php-gdHow to create transparent PNG

This code creates and saves PNG image with black circle on a transparent background:

<?php

$im = imagecreatetruecolor(400, 300);

imagealphablending($im, false);
$tr = imagecolorallocatealpha($im, 0, 0, 0, 255);
imagefill($im, 0, 0, $tr);
imagesavealpha($im, true);

$c_black = imageColorAllocate($im, 0,0,0);
imagefilledellipse($im, 200, 150, 100, 100, $c_black);

imagePng($im, '/tmp/image.png');ctrl + cgithub

`imagecreatetruecolor` creates true color GD image object with specified width & height	`imagealphablending` we're disabling alpha blending to prevent transparent background being converted to black color
`imagecolorallocatealpha` creates color with transparency (in our case, we just create fully transparent color)	`imagefill(` fills an entire image with a given color (green in our case)
`imagesavealpha` we're enabling alpha channel (controls transparency) for resulting image	`imageColorAllocate` creates color object to later use in image
`imagefilledellipse` creates ellipse with specified coordinates, radius and color	`imagePng` saves image in PNG format to the given path

More of Php Gd

See more codes...

php-gdHow to create transparent PNG

Related

More of Php Gd