试图保持png copyimage的透明度

Question

我试图保持图像的透明度，如果有任何重新采样后但仍然会以黑色背景返回？ $ image_copy是新图像，之后会显示。

$new_width  = round($new_width, 0);
$new_height = round($new_height, 0);

$image_r = imagecreatetruecolor( $new_width, $new_height );
imagealphablending( $image_r, false );
imagesavealpha( $image_r, true );
imagecopyresampled( $image_r, $image, 0, 0, 0, 0, $new_width, $new_height, $image_width, $image_height);
imagedestroy($image);

if ($new_width > $width) $offset_width = ($new_width - $width) / 2;
if ($new_height > $height) $offset_height = ($new_height - $height) / 2;

$image_copy = imagecreatetruecolor($width, $height);
imagecopy($image_copy, $image_r, 0, 0, $offset_width, $offset_height, $width, $height);
imagedestroy($image_r);

imagepng($image_copy,"{$filename}.png", 9)

任何帮助都会很棒？

Answer 1

也许您想查看此链接，希望它会有所帮助

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