PHP实现图片不变型裁剪及图片按比例裁剪的方法

本文实例讲述了PHP实现图片不变型裁剪及图片按比例裁剪的方法。分享给大家供大家参考，具体如下：

图片不变型裁剪

<?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);?>

图片按比例裁剪

<?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);?>