php实现在服务器端调整图片大小的方法
这篇文章主要介绍了php实现在服务器端调整图片大小的方法,实例分析了imageResizer与loadimage操作图片的相关技巧,需要的朋友可以参考下
本文实例讲述了php实现在服务器端调整图片大小的方法。分享给大家供大家参考。具体分析如下:
在服务器端完成图片大小的调整,会比在浏览器的处理有很多的好处。
本文介绍了PHP如何在服务器端调整图片大小。
代码包括两部分:
① imageResizer() is used to process the image
② loadimage() inserts the image url in a simpler format
- <?php
- function imageResizer($url, $width, $height) {
- header('Content-type: image/jpeg');
- list($width_orig, $height_orig) = getimagesize($url);
- $ratio_orig = $width_orig/$height_orig;
- if ($width/$height > $ratio_orig) {
- $width = $height*$ratio_orig;
- } else {
- $height = $width/$ratio_orig;
- }
- // This resamples the image
- $image_p = imagecreatetruecolor($width, $height);
- $image = imagecreatefromjpeg($url);
- imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);
- // Output the image
- imagejpeg($image_p, null, 100);
- }
- //works with both POST and GET
- $method = $_SERVER['REQUEST_METHOD'];
- if ($method == 'GET') {
- imageResize($_GET['url'], $_GET['w'], $_GET['h']);
- } elseif ($method == 'POST') {
- imageResize($_POST['url'], $_POST['w'], $_POST['h']);
- }
- // makes the process simpler
- function loadImage($url, $width, $height){
- echo 'image.php?url=', urlencode($url) ,
- '&w=',$width,
- '&h=',$height;
- }
- ?>
用法:
- //Above code would be in a file called image.php.
- //Images would be displayed like this:
- <img src="<?php loadImage('image.jpg', 50, 50) ?>" alt="" />