問題:
The following PHP code snippet uses GD to resize a browser-uploaded PNG to 128x128. 以下PHP代碼段使用GD將瀏覽器上傳的PNG調整爲128x128。 It works great, except that the transparent areas in the original image are being replaced with a solid color- black in my case. 效果很好,只是在我的情況下,原始圖像中的透明區域已被替換爲純黑色。
Even though imagesavealpha
is set, something isn't quite right. 即使設置了imagesavealpha
,也不是很正確。
What's the best way to preserve the transparency in the resampled image? 在重新採樣的圖像中保留透明度的最佳方法是什麼?
$uploadTempFile = $myField[ 'tmp_name' ]
list( $uploadWidth, $uploadHeight, $uploadType )
= getimagesize( $uploadTempFile );
$srcImage = imagecreatefrompng( $uploadTempFile );
imagesavealpha( $targetImage, true );
$targetImage = imagecreatetruecolor( 128, 128 );
imagecopyresampled( $targetImage, $srcImage,
0, 0,
0, 0,
128, 128,
$uploadWidth, $uploadHeight );
imagepng( $targetImage, 'out.png', 9 );