DJVU file decoding - where is the bzz stream?

The task: I'd like to take a single DJVU file and manually break it down into its components, for instructional purposes. Details: I have a small one-page DJVU file, consisting of a 16-byte DJVU header ("INFO"), and then a single Sjbz stream. However, I am confused about how to interpret the Sjbz stream. If I understand correctly, the Sjbz stream is encoded with a series of compressions (ZPCODEC, and BZZ, and JB), and that it is necessary to go through all those levels in order to get to the bi-tonal data itself. However, I tried taking the data that immediately comes after the Sjbz marker, saving it in a file, and passing it to "[login to view URL]" for decoding, and it says that the stream is corrupt. So I must not be understanding the stream correctly. I'd like to pay for someone to take my file and explain to me how the Sjbz stream is encoding, and to explain how to get from the Sjbz stream to the actual Bitonal data.