response headers too large for /index.php

Question

I cannot base64decode large files in php.

Here is my code;

Flight::route('/Upgrades/MainUpload', function() {

    $rawBody = Configuration::GetRawBody();

    $base64Part = explode('=', $rawBody, 2)[1];

    $choppedBase64 = substr($base64Part, 31);

    $bytestring = base64_decode(html_entity_decode($choppedBase64), true);

    $b = array();
    foreach(str_split($bytestring) as $c)
        $b[] = sprintf("%08b", ord($c));

    echo var_dump($b);


});

If i try a small file it works, however a big file, does not work and i just get for byte array $b - > one record with 0000000 in it.

I am sure there is a idiotic configuration somewhere but for the life of me i cannot find it.

Here is the link to the php.ini file:

http://s000.tinyupload.com/index.php?file_id=39557226798953894915