How to implement invariant cropping of images and proportional cropping of images in PHP

The example in this article describes the method of implementing invariant cropping of images and proportional cropping of images in PHP. Share it with everyone for your reference, the details are as follows:

Picture unchanged cropping

<&#63;php
/**
 * imageCropper
 * @param string $source_path
 * @param string $target_width
 * @param string $target_height
 */
function imageCropper($source_path, $target_width, $target_height){
  $source_info  = getimagesize($source_path);
  $source_width = $source_info[0];
  $source_height = $source_info[1];
  $source_mime  = $source_info['mime'];
  $source_ratio = $source_height / $source_width;
  $target_ratio = $target_height / $target_width;
  if ($source_ratio > $target_ratio){
    // image-to-height
    $cropped_width = $source_width;
    $cropped_height = $source_width * $target_ratio;
    $source_x = 0;
    $source_y = ($source_height - $cropped_height) / 2;
  }elseif ($source_ratio < $target_ratio){
    //image-to-widht
    $cropped_width = $source_height / $target_ratio;
    $cropped_height = $source_height;
    $source_x = ($source_width - $cropped_width) / 2;
    $source_y = 0;
  }else{
    //image-size-ok
    $cropped_width = $source_width;
    $cropped_height = $source_height;
    $source_x = 0;
    $source_y = 0;
  }
  switch ($source_mime){
    case 'image/gif':
      $source_image = imagecreatefromgif($source_path);
      break;
    case 'image/jpeg':
      $source_image = imagecreatefromjpeg($source_path);
      break;
    case 'image/png':
      $source_image = imagecreatefrompng($source_path);
      break;
    default:
      return ;
      break;
  }
  $target_image = imagecreatetruecolor($target_width, $target_height);
  $cropped_image = imagecreatetruecolor($cropped_width, $cropped_height);
  // copy
  imagecopy($cropped_image, $source_image, 0, 0, $source_x, $source_y, $cropped_width, $cropped_height);
  // zoom
  imagecopyresampled($target_image, $cropped_image, 0, 0, 0, 0, $target_width, $target_height, $cropped_width, $cropped_height);
  header('Content-Type: image/jpeg');
  imagejpeg($target_image);
  imagedestroy($source_image);
  imagedestroy($target_image);
  imagedestroy($cropped_image);
}
$filename = "8fcb7a0831b79c61.jpg";
imageCropper($filename,200,200);
&#63;>

Picture proportional cropping

<&#63;php
/**
 * imageZoom
 * @param string $file
 * @param double $zoom
 */
function imageZoom($filename,$zoom=0.6){
  //baseinfo
  $sourceImageInfo = getimagesize($filename);
  $sourceWidth = $sourceImageInfo[0];
  $sourceHeight = $sourceImageInfo[1];
  $sourceMine = $sourceImageInfo['mime'];
  $sourceRatio = $sourceWidth/$sourceHeight;
  $sourceX = 0;
  $sourceY = 0;
  //zoom
  $targetRatio = $zoom;
  //target-widht-height
  $targetWidth = $sourceWidth*$targetRatio;
  $targetHeight = $sourceHeight*$targetRatio;
  //init-params
  $sourceImage = null;
  switch($sourceMine){
    case 'image/gif':
      $sourceImage = imagecreatefromgif($filename);
      break;
    case 'image/jpeg':
      $sourceImage = imagecreatefromjpeg($filename);
      break;
    case 'image/png':
      $sourceImage = imagecreatefrompng($filename);
      break;
    default:
      return ;
      break;
  }
  //temp-target-image
  $tempSourceImage = imagecreatetruecolor($sourceWidth, $sourceHeight);
  $targetImage = imagecreatetruecolor($targetWidth,$targetHeight);
  //copy
  imagecopy($tempSourceImage, $sourceImage, 0, 0, $sourceX, $sourceY, $sourceWidth, $sourceHeight);
  //zoom
  imagecopyresampled($targetImage, $tempSourceImage, 0, 0, 0, 0, $targetWidth, $targetHeight, $sourceWidth, $sourceHeight);
  //header
  header('Content-Type: image/jpeg');
  //image-loading
  imagejpeg($targetImage);
  //destroy
  imagedestroy($tempSourceImage);
  imagedestroy($sourceImage);
  imagedestroy($targetImage);
}
$filename = "8fcb7a0831b79c61.jpg";
imageZoom($filename);
&#63;>

I hope this article will be helpful to everyone in PHP program design.

The above introduces the method of implementing image invariant cropping and proportional cropping of images in PHP, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.