求救：老师遇到问题：Warning: imagecreatefromjpeg(): gd-jpeg: JPEG library reports unrecoverable error:
Warning: imagecreatefromjpeg(): gd-jpeg: JPEG library reports unrecoverable error:
Warning: imagecreatefromjpeg(): '1.jpg' is not a valid JPEG file in
( ! ) Warning: imagejpeg() expects parameter 1 to be resource, boolean given in
运行第一个测试时遇到这几个提示，是因为php版本太高的原因吗？
代码如下，我检查过一遍并没有检查出来问题：
<?php
$filename="1.jpg";
$src_image=imagecreatefromjpeg($filename);
list($src_w,$src_h)=getimagesize($filename);
$scale=0.5;
$dst_w=ceil($src_w*$scale);
$dst_h=ceil($src_h*$scale);
$dst_image=imagecreatetruecolor($dst_w, $dst_h);
imagecopyresampled($dst_image, $src_image, 0, 0, 0, 0, $dst_w, $dst_h, $src_w, $src_h);
header("content-type:image/jpeg");
imagejpeg($dst_image);
imagedestroy($src_image);
imagedestroy($dst_image);
