php生成图片缩略图的方法

 function make_thumb($src,$dest,$desired_width) { /* read the source image */ $source_image = imagecreatefromjpeg($src); $width = imagesx($source_image); $height = imagesy($source_image); /* find the "desired height" of this thumbnail, relative to the desired width */ $desired_height = floor($height*($desired_width/$width)); /* create a new, "virtual" image */ $virtual_image = imagecreatetruecolor($desired_width,$desired_height); /* copy source image at a resized size */ imagecopyresized($virtual_image,$source_image,0,0,0,0,$desired_width,$desired_height,$width,$height); /* create the physical thumbnail image to its destination */ imagejpeg($virtual_image,$dest, 83); }