這篇文章主要介紹了PHP圖片等比縮放類SimpleImage使用方法和使用實例分享,需要的朋友可以參考下
使用方法示例： 設定寬度，等比例縮放 代碼如下: <?php include('SimpleImage.php'); $image = new SimpleImage(); $image->load('picture.jpg'); $image->resizeToWidth(250); $image->save('picture2.jpg');?> 設定高度，等比例縮放 代碼如下: <?php include('SimpleImage.php'); $image = new SimpleImage(); $image->load('picture.jpg'); $image->resizeToHeight(500); $image->save('picture2.jpg'); $image->resizeToHeight(200); $image->save('picture3.jpg');?> 按比例，縮放至50% 代碼如下: <?php include('SimpleImage.php'); $image = new SimpleImage(); $image->load('picture.jpg'); $image->scale(50); $image->save('picture2.jpg');?> 縮放後直接輸出到屏幕 代碼如下: <?php header('Content-Type: image/jpeg'); include('SimpleImage.php'); $image = new SimpleImage(); $image->load('picture.jpg'); $image->resizeToWidth(150); $image->output();?> 使用例子： 代碼如下: <?php include("SimpleImage.php");//圖片處理類在下面 $url="http://f3.v.veimg.cn/meadincms/1/2013/0703/20130703100937552.jpg"; $picfile = down($url);//下載圖片（下載圖片的路徑可以處理完成後清空，這裡未進行處理） $res = new SimpleImage();//圖片處理實例 $res = $res->load($picfile); $tmpfile = tempfile().'.jpg';//創建一個路徑文件用來保存圖片 $width = '30';//設定圖片的寬度 $res->resizeToWidth($width); $res->save($tmpfile);//把處理後的圖片保存（無.jpg後綴） //這裡總共產生了3個文件，一個是下載的圖片文件，一個是臨時文件，最後一個是處理的圖片文件。需要優化清理掉前兩個文件。 function down($url) { $http = array(); $header = "http://f3.v.veimg.cn"; if ($header) { $http['header'] = $header; } $http['timeout'] = 50; $ctx = stream_context_create(array( 'http' => $http, )); $content = @file_get_contents($url, 0, $ctx); sleep(1); if (!$content) { return false; } $tmpfile = tempfile(); file_put_contents($tmpfile, $content); return $tmpfile; } function tempfile() { $path = dirname(__FILE__); $path .= '/spider/' . date('Ymd') . '/'.date('His').'-' . (int)(time() / 300); if (!file_exists($path)) { mkdir($path, 0777, true); } do { $file = $path . '/' . dechex(mt_rand()); } while (file_exists($file)); touch($file); return $file; } 圖片處理類源碼（官網地址：http://www.white-hat-web-design.co.uk/blog/resizing-images-with-php/）： 代碼如下: <?php /* * File: SimpleImage.php * Author: Simon Jarvis * Copyright: 2006 Simon Jarvis * Date: 08/11/06 * Link: http://www.white-hat-web-design.co.uk/articles/php-image-resizing.php * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details: * http://www.gnu.org/licenses/gpl.html * */ class SimpleImage { var $image; var $image_type; function load($filename) { $image_info = getimagesize($filename); $this->image_type = $image_info[2]; if( $this->image_type == IMAGETYPE_JPEG ) { $this->image = @imagecreatefromjpeg($filename); } elseif( $this->image_type == IMAGETYPE_GIF ) { $this->image = @imagecreatefromgif($filename); } elseif( $this->image_type == IMAGETYPE_PNG ) { $this->image = @imagecreatefrompng($filename); } if (!$this->image) { return false; } return $this; } function save($filename, $image_type=IMAGETYPE_JPEG, $compression=75, $permissions=null) { if( $image_type == IMAGETYPE_JPEG ) { imagejpeg($this->image,$filename,$compression); } elseif( $image_type == IMAGETYPE_GIF ) { imagegif($this->image,$filename); } elseif( $image_type == IMAGETYPE_PNG ) { imagepng($this->image,$filename); } if( $permissions != null) { chmod($filename,$permissions); } } function output($image_type=IMAGETYPE_JPEG) { if( $image_type == IMAGETYPE_JPEG ) { imagejpeg($this->image); } elseif( $image_type == IMAGETYPE_GIF ) { imagegif($this->image); } elseif( $image_type == IMAGETYPE_PNG ) { imagepng($this->image); } } function getWidth() { return imagesx($this->image); } function getHeight() { return imagesy($this->image); } function resizeToHeight($height) { $ratio = $height / $this->getHeight(); $width = $this->getWidth() * $ratio; $this->resize($width,$height); } function resizeToWidth($width) { if ($this->getWidth() < $width) { $width = $this->getWidth(); } $ratio = $width / $this->getWidth(); $height = $this->getheight() * $ratio; $this->resize($width,$height); } function scale($scale) { $width = $this->getWidth() * $scale/100; $height = $this->getheight() * $scale/100; $this->resize($width,$height); } function resize($width,$height) { $new_image = imagecreatetruecolor($width, $height); imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight()); $this->image = $new_image; } function resize2($width,$height) { $new_image = imagecreatetruecolor($width, $height); if( $this->image_type == IMAGETYPE_GIF || $this->image_type == IMAGETYPE_PNG ) { $current_transparent = imagecolortransparent($this->image); if($current_transparent != -1) { $transparent_color = imagecolorsforindex($this->image, $current_transparent); $current_transparent = imagecolorallocate($new_image, $transparent_color['red'], $transparent_color['green'], $transparent_color['blue']); imagefill($new_image, 0, 0, $current_transparent); imagecolortransparent($new_image, $current_transparent); } elseif( $this->image_type == IMAGETYPE_PNG) { imagealphablending($new_image, false); $color = imagecolorallocatealpha($new_image, 0, 0, 0, 127); imagefill($new_image, 0, 0, $color); imagesavealpha($new_image, true); } } imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight()); $this->image = $new_image; } }
