我需要将图片大小调整为固定大小。但它不起作用并且有错误,我该怎么办?
在线演示:http://codepad.org/3OrIHfoy
ERROR:
致命错误:在线调用未定义的函数imagecreatefromjpeg() 58
PHP:
<?php
function thumbnail_box($img, $box_w, $box_h) {
//create the image, of the required size
$new = imagecreatetruecolor($box_w, $box_h);
if($new === false) {
//creation failed -- probably not enough memory
return null;
}
//Fill the image with a light grey color
//(this will be visible in the padding around the image,
//if the aspect ratios of the image and the thumbnail do not match)
//Replace this with any color you want, or comment it out for black.
//I used grey for testing =)
$fill = imagecolorallocate($new, 200, 200, 205);
imagefill($new, 0, 0, $fill);
//compute resize ratio
$hratio = $box_h / imagesy($img);
$wratio = $box_w / imagesx($img);
$ratio = min($hratio, $wratio);
//if the source is smaller than the thumbnail size,
//don't resize -- add a margin instead
//(that is, dont magnify images)
if($ratio > 1.0)
$ratio = 1.0;
//compute sizes
$sy = floor(imagesy($img) * $ratio);
$sx = floor(imagesx($img) * $ratio);
//compute margins
//Using these margins centers the image in the thumbnail.
//If you always want the image to the top left,
//set both of these to 0
$m_y = floor(($box_h - $sy) / 2);
$m_x = floor(($box_w - $sx) / 2);
//Copy the image data, and resample
//
//If you want a fast and ugly thumbnail,
//replace imagecopyresampled with imagecopyresized
if(!imagecopyresampled($new, $img,
$m_x, $m_y, //dest x, y (margins)
0, 0, //src x, y (0,0 means top left)
$sx, $sy,//dest w, h (resample to this size (computed above)
imagesx($img), imagesy($img)) //src w, h (the full size of the original)
) {
//copy failed
imagedestroy($new);
return null;
}
//copy successful
return $new;
}
$i = imagecreatefromjpeg("http://techstroke.com/wp-content/uploads/2008/12/image2.png");
$thumb = thumbnail_box($i, 210, 150);
imagedestroy($i);
if(is_null($thumb)) {
/* image creation or copying failed */
header('HTTP/1.1 500 Internal Server Error');
exit();
}
header('Content-Type: image/jpeg');
imagejpeg($thumb);
答案 0 :(得分:0)
那个错误......
Fatal error: Call to undefined function imagecreatefromjpeg() on line 58
imagecreatefromjpeg()
不可调用,因为它不存在。这意味着尚未在您的系统上安装GD库。
here are the installation notes。你需要它们才能让一切顺利。因为你从互联网上获取了这个php功能,所以一旦你安装了GD库就可以正常工作。