Also don't forget about non-english encodings in which form data can be sent (english coders often forget about it :-) ). IMO, presence of 0x00..0x1F bytes in such data as HTTP response can mark it as binary (unless the form is sent in utf-8). So maybe you should take into consideration charset from Content-Type header and only then analyze byte/character stream.
in reply to Re: Distinguishing text from binary data
in thread Distinguishing text from binary data