How to read N bytes instead of N characters?

[Peng Yu]

Hi,

help read says this.
...
      -n nchars    return after reading NCHARS characters rather than waiting
            for a newline, but honor a delimiter if fewer than
            NCHARS characters are read before the delimiter
      -N nchars    return only after reading exactly NCHARS characters, unless
            EOF is encountered or read times out, ignoring any
            delimiter

Is there a way to read N bytes instead of N chars in bash? Thanks.

-- 
Regards,
Peng