The MIDI Data Chunk can be used to store MIDI data (please refer to Musical Instrument Digital Interface Specification 1.0, available from the International MIDI Association, for more details on MIDI).
The primary purpose of this chunk is to store MIDI System Exclusive messages, although other types of MIDI data can be stored in this block as well. As more instruments come on the market, they will likely have parameters that have not been included in the Audio IFF specification. The MIDI System Exclusive messages for these instruments may contain many parameters that are not included in the Instrument Chunk. For example, a new sampling instrument may have more than the two loops defined in the Instrument Chunk. These loops will likely be represented in the MIDI System Exclusive message for the new machine. This MIDI System Exclusive message can be stored in the MIDI Data Chunk.
typedef struct {
#define MIDIDataID 'MIDI' /* ckID for MIDI Data Chunk */
} MIDIDataChunk;
ckID is always ' MIDI'. ckSize is the size of the data portion of the chunk, in bytes. It does not include the 8 bytes used by ckID and ckSize.
MIDIData contains a stream of MIDI data.
The MIDI Data Chunk is optional. Any number of MIDI Data Chunks may exist in a FORM AIFF. If MIDI System Exclusive messages for several instruments are to be stored in a FORM AIFF, it is better to use one MIDI Data Chunk per instrument than one big MIDI Data Chunk for all of the instruments.
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