DDEX messages allow categorising Resources in several ways:
- Firstly by separating sound recordings from videos, MIDI resources(*), images, text resources, pieces of software and sheet music. Each of these resource types have different attributes (e.g. a video might have a screen resolution whereas a MIDI resource may have an indication of the sound processor used to turn the MIDI instructions into sound waves.)
- Secondly by classifying each of the main types. A list of the types of sound recordings is shown on the right.
Some companies use the information to automatically process data received. A Works licensor may, for instance automatically levy a royalty on all sound recordings being classified as being based on a MusicalWork. It is therefore essential for all message senders to ensure that correct resource types are provided.
(*) MIDIs are no longer available in ERN-4. Please use sound recordings instead.