The 'Copyright message' frame, in which the string must begin with a
year and a space character (making five characters), is intended for
the copyright holder of the original sound, not the audio file
itself. The absence of this frame means only that the copyright
information is unavailable or has been removed, and must not be
interpreted to mean that the audio is public domain. Every time this
field is displayed the field must be preceded with "Copyright " (C) "
", where (C) is one character showing a C in a circle.
@author Eric Farng
@version $Revision: 1.4 $