Sharing code for scaling images and cutting images in PHP,

Sharing code for scaling images and cutting images in PHP, _PHP tutorial

WBOY

Release： 2016-07-12 08:59:16

Original

1140 people have browsed it

Sharing of PHP code for scaling images and cutting images at equal proportions,

Sharing PHP code for scaling images and cutting images at equal proportions

/**
 * 图片缩放函数（可设置高度固定，宽度固定或者最大宽高，支持gif/jpg/png三种类型）
 * Author : Specs
 *
 * @param string $source_path 源图片
 * @param int $target_width 目标宽度
 * @param int $target_height 目标高度
 * @param string $fixed_orig 锁定宽高（可选参数 width、height或者空值）
 * @return string
 */
function myImageResize($source_path, $target_width = 200, $target_height = 200, $fixed_orig = ''){
  $source_info = getimagesize($source_path);
  $source_width = $source_info[0];
  $source_height = $source_info[1];
  $source_mime = $source_info['mime'];
  $ratio_orig = $source_width / $source_height;
  if ($fixed_orig == 'width'){
    //宽度固定
    $target_height = $target_width / $ratio_orig;
  }elseif ($fixed_orig == 'height'){
    //高度固定
    $target_width = $target_height * $ratio_orig;
  }else{
    //最大宽或最大高
    if ($target_width / $target_height > $ratio_orig){
      $target_width = $target_height * $ratio_orig;
    }else{
      $target_height = $target_width / $ratio_orig;
    }
  }
  switch ($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 false;
      break;
  }
  $target_image = imagecreatetruecolor($target_width, $target_height);
  imagecopyresampled($target_image, $source_image, 0, 0, 0, 0, $target_width, $target_height, $source_width, $source_height);
  //header('Content-type: image/jpeg');
  $imgArr = explode('.', $source_path);
  $target_path = $imgArr[0] . '_new.' . $imgArr[1];
  imagejpeg($target_image, $target_path, 100);
}

Copy after login

Usage:

myImageResize($filename, 200, 200); //Maximum width and height
myImageResize($filename, 200, 200, 'width'); //Fixed width
myImageResize($filename, 200, 200, 'height'); //Fixed height

Cut the image to a fixed size:

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;
  
  // 源图过高
  if ($source_ratio > $target_ratio){
    $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){ // 源图过宽
    $cropped_width = $source_height / $target_ratio;
    $cropped_height = $source_height;
    $source_x = ($source_width - $cropped_width) / 2;
    $source_y = 0;
  }else{ // 源图适中
    $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 false;
      break;
  }
  
  $target_image = imagecreatetruecolor($target_width, $target_height);
  $cropped_image = imagecreatetruecolor($cropped_width, $cropped_height);
  
  // 裁剪
  imagecopy($cropped_image, $source_image, 0, 0, $source_x, $source_y, $cropped_width, $cropped_height);
  // 缩放
  imagecopyresampled($target_image, $cropped_image, 0, 0, 0, 0, $target_width, $target_height, $cropped_width, $cropped_height);
  $dotpos = strrpos($source_path, '.');
  $imgName = substr($source_path, 0, $dotpos);
  $suffix = substr($source_path, $dotpos);
  $imgNew = $imgName . '_small' . $suffix;
  imagejpeg($target_image, $imgNew, 100);
  imagedestroy($source_image);
  imagedestroy($target_image);
  imagedestroy($cropped_image);
}

Copy after login

Articles you may be interested in:

Examples of image scaling in PHP
Introduction to examples of php scaling images (according to the proportion of width and height)
PHP uploads images with equal proportions to add watermark function
Sharing the PHP image proportional scaling to generate thumbnail function
PHP realizes equal proportional scaling to generate uploaded image thumbnails according to the specified size Method
php code to achieve equal scaling of images
How to achieve equal scaling of images in php