PHP achieves constant image cropping and proportional Image cropping

This article mainly introduces PHP's methods for cropping images without changing the image size and proportional image size, and involves common PHP techniques for cropping thumbnails, for more information, see the example in this article, which describes how PHP can crop images without changing the image type and how to crop images proportionally. We will share this with you for your reference. The details are as follows:

Crop images unchanged

<?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);?>

Crop images proportionally

<?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);?>

I hope this article will help you with PHP programming.