01// 剪切图片 02functioncut_img($src_image, $out_image = null, int $new_width = null, int $new_height = null, $img_quality = 90) 03{ 04// 输出地址 05if(! $out_image) 06$out_image = $src_image; 07 08// 读取配置文件设置 09if(! $new_width && ! $new_height) 10return; 11 12// 获取图片属性 13list ($width, $height, $type, $attr) = getimagesize($src_image); 14switch ($type) { 15case1: 16$img = imagecreatefromgif($src_image); 17break; 18case2: 19$img = imagecreatefromjpeg($src_image); 20break; 21case3: 22$img = imagecreatefrompng($src_image); 23break; 24} 25 26// 不限定是等比例缩放 27if(! $new_width) { 28$new_width = floor($width * ($new_height / $height)); 29} 30if(! $new_height) { 31$new_height = floor($height * ($new_width / $width)); 32} 33// 创建画布 34$new_img = imagecreatetruecolor($new_width, $new_height); 35 36// 创建透明画布,避免黑色 37if($type== 1 || $type== 3) { 38$color = imagecolorallocate($new_img, 255, 255, 255); 39imagefill($new_img, 0, 0, $color); 40imagecolortransparent($new_img, $color); 41} 42 43 44// 先缩放 45$scale = max($new_width / $width, $new_height / $height); 46$scale_width = floor($scale * $width); 47$scale_height = floor($scale * $height); 48$scale_img = imagecreatetruecolor($scale_width, $scale_height); // 创建画布 49if(function_exists("ImageCopyResampled")) { 50imagecopyresampled($scale_img, $img, 0, 0, 0, 0, $scale_width, $scale_height, $width, $height); 51} else{ 52imagecopyresized($scale_img, $img, 0, 0, 0, 0, $scale_width, $scale_height, $width, $height); 53} 54//再裁剪 55$start_x = ($scale_width - $new_width) / 2; 56$start_y = ($scale_height - $new_height) / 2; 57 58//拷贝剪切的图像数据到画板，生成剪切图像 59imagecopy($new_img, $scale_img, 0, 0, $start_x, $start_y, $scale_width, $scale_height); 60 61check_dir(dirname($out_image), true); // 检查输出目录 62 63switch ($type) { 64case1: 65imagegif($new_img, $out_image, $img_quality); 66break; 67case2: 68imagejpeg($new_img, $out_image, $img_quality); 69break; 70case3: 71imagepng($new_img, $out_image, $img_quality / 10); // $quality参数取值范围0-99 在php 5.1.2之后变更为0-9 72break; 73default: 74imagejpeg($new_img, $out_image, $img_quality); 75} 76imagedestroy($new_img); 77imagedestroy($img); 78returntrue; 79} | 
