PHP按比例调整图像大小宽度或重量[关闭]

2 回答

• 12

  您只需要宽高比 . 这些方面的东西：

  $fn = $_FILES['image']['tmp_name'];
  $size = getimagesize($fn);
  $ratio = $size[0]/$size[1]; // width/height
  if( $ratio > 1) {
      $width = 500;
      $height = 500/$ratio;
  }
  else {
      $width = 500*$ratio;
      $height = 500;
  }
  $src = imagecreatefromstring(file_get_contents($fn));
  $dst = imagecreatetruecolor($width,$height);
  imagecopyresampled($dst,$src,0,0,0,0,$width,$height,$size[0],$size[1]);
  imagedestroy($src);
  imagepng($dst,$target_filename_here); // adjust format as needed
  imagedestroy($dst);
  

  您需要添加一些错误检查，但这应该让您开始 .

  回复于 2024-04-30T13:27:02+08:00
• 32

  使用Colin Verot编写的上传类 . 它有各种选项可用于调整大小，编辑，水印等......真棒！

  该课程由互联网上的网站维护和使用，因此您可以信赖它是可靠的！

  见here

  Even though this is called the Upload Class, you can apply the same methods to files already on your server

  如何使用

  按照网站上的安装说明，简单地下载课程并将其放在您的网站上 .

  您的脚本将如下所示：

  // Include the upload class
  include('class.upload.php');
  
  // Initiate the upload object based on the uploaded file field
  $handle = new upload($_FILES['image_field']);
  
  // Only proceed if the file has been uploaded
  if($handle->uploaded) {
      // Set the new filename of the uploaded image
      $handle->file_new_name_body   = 'image_resized';
      // Make sure the image is resized
      $handle->image_resize         = true;
      // Set the width of the image
      $handle->image_x              = 100;
      // Ensure the height of the image is calculated based on ratio
      $handle->image_ratio_y        = true;
      // Process the image resize and save the uploaded file to the directory
      $handle->process('/home/user/files/');
      // Proceed if image processing completed sucessfully
      if($handle->processed) {
          // Your image has been resized and saved
          echo 'image resized';
          // Reset the properties of the upload object
          $handle->clean();
      }else{
          // Write the error to the screen
          echo 'error : ' . $handle->error;
      }
  }
  

  回复于 2024-04-30T13:27:02+08:00