Well , when you encode any file you must make it logic. for example an encoded html text for example :
will be encoded as
so with a html decoder you get back the original value.
I have seen that some peoples are encoding entire pages with base64 but this method is easy to recognize and to decrypt using php's base64_decode function. Anyway , this function is php-made and is recognized by browsers. I have used that algorithm to to encode direct links to media files on my website and make sure nobody can get them. I haven't tryed to encode an entire page but i think will work with some encoding.
I should ask this before : do you want to hide source code in browser or in file?