Adding an audio sequence

To add an new type of audio sequence, you derive a new type of sequence from TAudioSequence and provide a TMediaSequenceCreator for the new sequence. The media sequence creator is used by the Media Registry to automatically associate a data file with the correct type of media sequence.

Providing an installation tool to register the sequence

To be recognized by the time-media frameworks, new sequence types must be registered with the Media Registry. The installation tool makes explicit calls to the Media Registry to install the new sequence class in the system. For example, if you have a TMediaSequence subclass that supports a new data type, you provide an installation tool that makes the class available to users. The installation tool:

  1. Creates an instance of your sequence class.
  2. Instantiates TMediaRegistryCaller.
  3. Calls TMediaRegistryCaller::AddSequenceCreator.
  4. Optionally sets the new sequence to be the default for that media type.
    The tool might also support the deregistration of sequence types.
Once your new sequence type is registered, the Media Registry can automatically associate that type of media data file with your new media sequence. All registered sequence types can be played by the convenience player classes.

When a user specifies a media data file to be played by a convenience player, the player uses the registry to associate the data file with the appropriate type of media sequence. To do this, the player instantiates a TMediaRegistryCaller and calls TMediaRegistryCaller::CreateSequence. The registry iterates through its collection of TMediaSequenceCreators until it finds the sequence type that matches the data file.

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