旋转图像后，更改背景

Question

它只在php中完成，在旋转原始图像后，图像的背景为黑色。如何消除背景？

下面是我的代码..

      $imgNames  = "upload/".$_SESSION["img"];
      $sourcea=imagecreatefromjpeg($imgNames);
      $rotatea=imagerotate($sourcea, 0,0); 
      $uniqids = uniqid();
      $rotImages = "upload/".$uniqids.".jpg";
      $uni=uniqid();
      imagejpeg($rotatea,$rotImages,$q=25);
      echo "Rotated Image: <img src='$rotImages' >";

Answer 1

只需使用css。因为你也标记了它。

.rotated{
transform:rotate(45deg); 
-ms-transform:rotate(45deg); 
-webkit-transform:rotate(45deg);
/*Or whatever deg you want*/
}

将该类添加到图像标记。

Answer 2

首先：* .jpg不支持透明度。 使用* .png图片格式。

第二：检查一下： How do i get a transparent background after rotaing a png image with php?

Answer 3

Add following code 



    $imgNames  = "upload/".$_SESSION["img"];
      $sourcea=imagecreatefromjpeg($imgNames);
    $transColor = imagecolorallocatealpha($imgNames, 255, 255, 255, 127);
         $rotatea=imagerotate($sourcea, 0,$transColor); 
        imagesavealpha($rotateae, true);
     $uniqids = uniqid();
      $rotImages = "upload/".$uniqids.".png";
      $uni=uniqid();
      imagejpeg($rotatea,$rotImages,$q=25);
      echo "Rotated Image: <img src='$rotImages' >";