Create transparent png with text from scratch in php
Here's the solution based on your original code.
<?php
$width = 640;
$height = 480;
$text = "My Text";
$fontsize = 5;
$img = imagecreate($width, $height);
// Transparent background
$black = imagecolorallocate($img, 0, 0, 0);
imagecolortransparent($img, $black);
// Red text
$red = imagecolorallocate($img, 255, 0, 0);
imagestring($img, $fontsize, 0, 0, $text, $red);
header('Content-type: image/png');
imagepng($img);
imagedestroy($img);
?>
<?php
$font = 25;
$string = 'My Text';
$im = @imagecreatetruecolor(strlen($string) * $font / 1.5, $font);
imagesavealpha($im, true);
imagealphablending($im, false);
$white = imagecolorallocatealpha($im, 255, 255, 255, 127);
imagefill($im, 0, 0, $white);
$lime = imagecolorallocate($im, 204, 255, 51);
imagettftext($im, $font, 0, 0, $font - 3, $lime, "droid_mono.ttf", $string);
header("Content-type: image/png");
imagepng($im);
imagedestroy($im);
?>
Use imagestring
instead of imagettftext
if you don't want custom font.