Question

I want to make transparent png image,and print string on it by imagefttext(by black color).
I read some example,I think I should use imagecolortransparent function,but it make image by black background.
how should I do it?

Answer 1

Try this

<?php
//Canvas size 100x50
$image = imagecreatetruecolor(100, 50);
imagealphablending($image, false);
//Create alpha channel for transparent layer
$col=imagecolorallocatealpha($image,255,255,255,127);
//Create overlapping 100x50 transparent layer
imagefilledrectangle($image,0,0,100, 50,$col);
//Continue to keep layers transparent
imagealphablending($image,true);
//Insert the text
imagefttext($image,10,0,10,20,0,'octin.ttf','test sting');
//Keep trnsparent when saving
imagesavealpha($image,true);

//Save & output
if(imagepng($image, "test.png", 1)){
   header("Content-Type: image/png");
   readfile('test.png');
}
imagedestroy($image);
?>

Output 100x50px [test.png]

whoops i forgot the r… my bad