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      TrackTitles => $disc_info->{ttitles},   # array reference
      From        => 'login@host.domain.etc', # will try to determine
    );

# DESCRIPTION

CDDB protocol (cddbp) servers provide compact disc information for
programs that need it.  This allows such programs to display disc and
track titles automatically, and it provides extended information like
liner notes and lyrics.

This module provides a high-level Perl interface to cddbp servers.
With it, a Perl program can identify and possibly gather details about
a CD based on its "table of contents" (the disc's track times and
offsets).

Disc details have been useful for generating CD catalogs, naming mp3
files, printing CD liners, or even just playing discs in an automated
jukebox.

Despite the module's name, it connects to FreeDB servers by default.
This began at version 1.04, when cddb.com changed its licensing model
to support end-user applications, not third-party libraries.
Connections to cddb.com may still work, and patches are welcome to
maintain that functionality, but it's no longer officially supported.

# PUBLIC METHODS

- new PARAMETERS

    Creates a high-level interface to a cddbp server, returning a handle
    to it.  The handle is not a filehandle.  It is an object.  The new()
    constructor provides defaults for just about everything, but
    everything is overrideable if the defaults aren't appropriate.

    The interface will not actually connect to a cddbp server until it's
    used, and a single cddbp interface may actually make several
    connections (to possibly several servers) over the course of its use.

    The new() constructor accepts several parameters, all of which have
    reasonable defaults.

    __Host__ and __Port__ describe the cddbp server to connect to.  These
    default to 'freedb.freedb.org' and 8880, which is a multiplexor for
    all the other freedb servers.

    __Utf8__ is a boolean flag. If true, utf-8 will be used when submitting
    CD info, and for interpreting the data reveived. This requires the
    [Encode](http://search.cpan.org/perldoc?Encode) module (and probably perl version at least 5.8.0). The
    default is true if the [Encode](http://search.cpan.org/perldoc?Encode) module can be loaded. Otherwise, it
    will be false, meaning we fall back to ASCII.

    __Protocol\_Version__ sets the cddbp version to use.  CDDB.pm will not
    connect to servers that don't support the version specified here.  The
    requested protocol version defaults to 1 if __Utf8__ is off, and to 6
    if it is on.

    __Login__ is the login ID you want to advertise to the cddbp server.
    It defaults to the login ID your computer assigns you, if that can be
    determined.  The default login ID is determined by the presence of a
    LOGNAME or USER environment variable, or by the getpwuid() function.
    On Windows systems, it defaults to "win32usr" if no default method can
    be found and no Login parameter is set.

    __Submit\_Address__ is the e-mail address where new disc submissions go.
    This defaults to 'freedb-submit@freedb.org'. Note, that testing
    submissions should be done via `test-submit@freedb.org`.

    __Client\_Name__ and __Client\_Version__ describe the client software used
    to connect to the cddbp server.  They default to 'CDDB.pm' and
    CDDB.pm's version number.  If developers change this, please consult
    freedb's web site for a list of client names already in use.

    __Debug__ enables verbose operational information on STDERR when set to
    true.  It's normally not needed, but it can help explain why a program
    is failing.  If someone finds a reproduceable bug, the Debug output
    and a test program would be a big help towards having it fixed.  In
    case of submission, if this flag is on, a copy of the submission
    e-mail will be sent to the _From_ address.

- get\_genres

    Takes no parameters.  Returns a list of genres known by the cddbp
    server, or undef if there is a problem retrieving them.

- calculate\_id TOC

    The cddb protocol defines an ID as a hash of track lengths and the
    number of tracks, with an added checksum. The most basic information
    required to calculate this is the CD table of contents (the CD-i track
    offsets, in "MSF" \[Minutes, Seconds, Frames\] format).

    Note however that there is no standard way to acquire this information
    from a CD-ROM device.  Therefore this module does not try to read the
    TOC itself.  Instead, developers must combine CDDB.pm with a CD
    library which works with their system.  The AudioCD suite of modules
    is recommended: it has system specific code for MacOS, Linux and
    FreeBSD.  CDDB.pm's author has used external programs like dagrab to
    fetch the offsets.  Actual CDs aren't always necessary: the author has
    heard of people generating TOC information from mp3 file lengths.

    That said, see parse\_cdinfo() for a routine to parse "cdinfo" output
    into a table of contents list suitable for calculate\_id().

    calculate\_id() accepts TOC information as a list of strings.  Each
    string contains four fields, separated by whitespace:

    offset 0: the track number

    Track numbers start with 1 and run sequentially through the number of
    tracks on a disc.  Note: data tracks count on hybrid audio/data CDs.

    CDDB.pm understands two special track numbers.  Track 999 holds the
    lead-out information, which is required by the cddb protocol.  Track
    1000 holds information about errors which have occurred while
    physically reading the disc.

    offset 1: the track start time, minutes field

    Tracks are often addressed on audio CDs using "MSF" offsets.  This
    stands for Minutes, Seconds, and Frames (fractions of a second).  The