php 判断图片文件的真实类型

<?php

/**

* 检测文件的真实类型

* @param  string $srcPath 文件路径

* @return string $realType 文件真实类型

*/

$imgurl = \’http://png.hkiii.cn/blog.png\’;

echo file_type_detect($imgurl);

function file_type_detect($srcPath){

    $types = array(

        6677    => \’bmp\’,

        7173    => \’gif\’,

        7368    => \’mp3\’,

        13780   => \’png\’,

        255216  => \’jpg\’,

    );

    $binary = curl_get($srcPath);

    $bytes = substr($binary, 0, 2);

    $head = @unpack(\’C2char\’, $bytes);

    $typeCode = intval($head[\’char1\’].$head[\’char2\’]);

    $realType = isset($types[$typeCode]) ? $types[$typeCode] : $typeCode;

    return $realType;

}

function curl_get($url){

    $ch=curl_init($url);

    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);

    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    curl_setopt($ch, CURLOPT_USERAGENT, \’Mozilla/5.0 (Linux; U; Android 4.4.1; zh-cn; R815T Build/JOP40D) AppleWebKit/533.1 (KHTML, like Gecko)Version/4.0 MQQBrowser/4.5 Mobile Safari/533.1\’);

    curl_setopt($ch, CURLOPT_TIMEOUT, 10);

    $content=curl_exec($ch);

    curl_close($ch);

    return($content);

}