PHP DECODE http raw POST data contain BINARY- application/octet-stream

i have a device that send POST data to my server. so print_r($_POST) is empty, i can see the data only when i run this $content = file_get_contents('php://input'); var_dump($content); //or i can use print_r($content); i save those to a file and result are some json and BINARY DATA (CHECK IMAGE in atachment) if i add code like this json_decode($content,true); i dont see anything so how can i decode that binary or what can i do to decode the json and also see what data is send in binary? p.s HTTP request Content-type is: [Content-Type] => application/octet-stream, application/octet-stream Please bid just if u can do this, if u are starter dont bid, coz this require more knowledge (dont waste my and your time)