php – 使用透明度调整图像PNG

内容导读

互联网集市收集整理的这篇技术教程文章主要介绍了php – 使用透明度调整图像PNG，小编现在分享给大家，供广大互联网技能从业者学习和参考。文章包含2192字，纯文字阅读大概需要4分钟。

内容图文

我想用透明plz帮助调整图像PNG的大小.
这是代码：

function resize($width,$height) {

  $new_image = imagecreatetruecolor($width, $height);

  imagealphablending($new_image, false);
  imagesavealpha($new_image,true);
  $transparent = imagecolorallocatealpha($new_image, 255, 255, 255, 127);
  imagefilledrectangle($new_image, 0, 0, $width, $height, $transparent);

  imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight());
  $this->image = $new_image;
}

解决方法:

试试这个

更新

function createThumb($upfile, $dstfile, $max_width, $max_height){
       $size = getimagesize($upfile);
       $width = $size[0];
       $height = $size[1];
       $x_ratio = $max_width / $width;
       $y_ratio = $max_height / $height;
       if( ($width <= $max_width) && ($height <= $max_height)) {
               $tn_width = $width;
               $tn_height = $height;
       } elseif (($x_ratio * $height) < $max_height) {
               $tn_height = ceil($x_ratio * $height);
               $tn_width = $max_width;
       } else {
               $tn_width = ceil($y_ratio * $width);
               $tn_height = $max_height;
       }
       if($size['mime'] == "image/jpeg"){
               $src = ImageCreateFromJpeg($upfile);
               $dst = ImageCreateTrueColor($tn_width, $tn_height);
               imagecopyresampled($dst, $src, 0, 0, 0, 0, $tn_width, $tn_height,$width, $height);
               imageinterlace( $dst, true);
               ImageJpeg($dst, $dstfile, 100);
       } else if ($size['mime'] == "image/png"){
               $src = ImageCreateFrompng($upfile);

    // integer representation of the color black (rgb: 0,0,0)
    $background = imagecolorallocate($src, 0, 0, 0);
    // removing the black from the placeholder
    imagecolortransparent($src, $background);

    // turning off alpha blending (to ensure alpha channel information 
    // is preserved, rather than removed (blending with the rest of the 
    // image in the form of black))
    imagealphablending($src, false);

    // turning on alpha channel information saving (to ensure the full range 
    // of transparency is preserved)
    imagesavealpha($src, true);
               $dst = ImageCreateTrueColor($tn_width, $tn_height);
               imagecopyresampled($dst, $src, 0, 0, 0, 0, $tn_width, $tn_height,$width, $height);
               Imagepng($dst, $dstfile);

       } else {

               $src = ImageCreateFromGif($upfile);
               $dst = ImageCreateTrueColor($tn_width, $tn_height);
               imagecopyresampled($dst, $src, 0, 0, 0, 0, $tn_width, $tn_height,$width, $height);
               imagegif($dst, $dstfile);
       }
    }

内容总结

以上是互联网集市为您收集整理的php – 使用透明度调整图像PNG全部内容，希望文章能够帮你解决php – 使用透明度调整图像PNG所遇到的程序开发问题。 如果觉得互联网集市技术教程内容还不错，欢迎将互联网集市网站推荐给程序员好友。

内容备注

版权声明：本文内容由互联网用户自发贡献，该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容， 请发送邮件至 gblab@vip.qq.com 举报，一经查实，本站将立刻删除。

内容手机端