PHP で画像の不変トリミングと画像の比例トリミングを実装する方法

この記事の例では、PHP で画像の不変トリミングと画像の比例トリミングを実装する方法を説明します。参考のために皆さんと共有してください。詳細は次のとおりです:

画像の変更なしトリミング

<&#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;>

画像の比例トリミング

<&#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;>

この記事が、PHP プログラム設計に携わる皆様のお役に立てれば幸いです。

上記は、PHP で画像の不変トリミングと画像の比例トリミングを実装する方法を、関連する内容も含めて紹介しました。PHP チュートリアルに興味のある友人の役に立てば幸いです。