图片存储 - 使用PHP保存图片同时保持源来图片的md5值

<code class="lang-php">/**
* 加载图片
* 
*/
$save_dir = APP.'tmp'.DS;
$url = 'http://su.bdimg.com/static/superplus/img/logo_white_ee663702.png';
$img = http_client_request( $url );

echo 'Curl获取的二进制流文件MD5值:<br>'.md5($img); //图片md5

$fp2=@fopen($save_dir.'baidu-save.png','a');
fwrite($fp2,$img);
fclose($fp2);
unset($img,$url);

echo "\n";
$fmd5 = '通过fwrite保存图片MD5:<br>'.md5_file($save_dir.'baidu-save.png');
echo $fmd5;

echo '原图md5:<br>'.md5_file($save_dir.'baidu-org.png');
</code>

<code class="lang-php">/**
* 加载图片
* 
*/
$save_dir = APP.'tmp'.DS;
$url = 'http://su.bdimg.com/static/superplus/img/logo_white_ee663702.png';
$img = http_client_request( $url );

echo 'Curl获取的二进制流文件MD5值:<br>'.md5($img); //图片md5

$fp2=@fopen($save_dir.'baidu-save.png','a');
fwrite($fp2,$img);
fclose($fp2);
unset($img,$url);

echo "\n";
$fmd5 = '通过fwrite保存图片MD5:<br>'.md5_file($save_dir.'baidu-save.png');
echo $fmd5;

echo '原图md5:<br>'.md5_file($save_dir.'baidu-org.png');
</code>

<code>xxd logo_white_ee663702.png > logo_white_ee663702.hex
xxd baidu-save.png > baidu-save.hex
diff logo_white_ee663702.hex baidu-save.hex
</code>