帮我看看为什么没error但是图片显示不出来

Question

<?php

$url = 'img/sex.jpg';

$content = file_get_contents($url);

$filename = 'img/sex.jpg';

file_put_contents($filename,$contents);

$yrl = 'img/logo.jpg';

file_put_contents('img/logo.jpg',file_get_contents($url));

$img = imagecreatefromjpeg($filename);

$logo = imagecreatefromjpeg('img/logo.jpg');

$size = getimagesize('img/logo.jpg');

imagecopy($img,$logo,15,15,0,0,$size[0],$size[1]);

header("content-type: image/jpeg");

imagejpeg($img);

?>

Answer 1

要加一个头才会显示图片的

Answer 2

什么头？