FileBitstreamReaderAgent Class
This class reads the bit stream (with the help of HeaderDecoder for tile headers and PktDecoder for packets header and body) and retrives location of all code-block's codewords.
Note: All tile-parts headers are read by the constructor whereas packets are processed when decoding related tile (when setTile method is called).
In parsing mode, the reader simulates a virtual layer-resolution progressive bit stream with the same truncation points in each code-block, whereas in truncation mode, only the first bytes are taken into account (it behaves like if it is a real truncated codestream).