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 image② 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="" />

希望本文所述对大家的php程序设计有所帮助。