imagepng 生成黑色图片背景

Question

Below is my image generate code:

$thumb = imagecreatetruecolor($newwidth, $newheight) or die('Cannot Initialize new GD image stream'); 
    print_r($thumb);
    $source = imagecreatefrompng($filename) or die('Cannot Initialize new GD image stream'); 
    print_r($source);
    imagecopyresampled($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
    @imagepng(  $thumb, $original_img_dir_absolute_path.$original_img_name, 0 );

it will generate first png but with black background only. anybody have idea about it.

Answer 1

Your code seems to be OK. You may check if the fragment does not take a black part of the original image. You can also try to remove your "quality" parameter of imagepng() :

imagepng($thumb, $original_img_dir_absolute_path . $original_img_name);

Maybe your original image have a low contrast, and the low quality shows you a black image.