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(python2.1-lib.info)Parser Objects

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Parser Objects
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Parser objects (returned by `createparser()') have the following
methods:

`addcallback(type, func, arg)'
     Adds a callback for the parser.  The parser has callbacks for eight
     different types of data in the digital audio data stream.
     Constants for these types are defined at the `cd' module level
     (see above).  The callback is called as follows: `FUNC(ARG, type,
     data)', where ARG is the user supplied argument, TYPE is the
     particular type of callback, and DATA is the data returned for
     this TYPE of callback.  The type of the data depends on the TYPE
     of callback as follows:

     Type                               Value
     ------                             -----
     audio                              String which can be passed
                                        unmodified to `al.writesamps()'.
     pnum                               Integer giving the program
                                        (track) number.
     index                              Integer giving the index number.
     ptime                              Tuple consisting of the program
                                        time in minutes, seconds, and
                                        frames.
     atime                              Tuple consisting of the absolute
                                        time in minutes, seconds, and
                                        frames.
     catalog                            String of 13 characters, giving
                                        the catalog number of the CD.
     ident                              String of 12 characters, giving
                                        the ISRC identification number of
                                        the recording.  The string
                                        consists of two characters
                                        country code, three characters
                                        owner code, two characters giving
                                        the year, and five characters
                                        giving a serial number.
     control                            Integer giving the control bits
                                        from the CD subcode data

`deleteparser()'
     Deletes the parser and frees the memory it was using.  The object
     should not be used after this call.  This call is done
     automatically when the last reference to the object is removed.

`parseframe(frame)'
     Parses one or more frames of digital audio data from a CD such as
     returned by `readda()'.  It determines which subcodes are present
     in the data.  If these subcodes have changed since the last frame,
     then `parseframe()' executes a callback of the appropriate type
     passing to it the subcode data found in the frame.  Unlike the C
     function, more than one frame of digital audio data can be passed
     to this method.

`removecallback(type)'
     Removes the callback for the given TYPE.

`resetparser()'
     Resets the fields of the parser used for tracking subcodes to an
     initial state.  `resetparser()' should be called after the disc
     has been changed.