SMF
Provides additional information like grouping events in tracks, and meta events like lyrics, track names, markers, tempo setting, time and key signatures, etc.
Spec
Track chunk
Offset Length Type Description Value
0x00 4 char[4] chunk ID "MTrk" (0x4D54726B)
0x04 4 dword chunk size
0x08
track event data
Track event data
Then event type
MIDI events
Note Off 0x8 note number velocity
Note On 0x9 note number velocity
Note Aftertouch 0xA note number aftertouch value
Controller 0xB controller number controller value
Program Change 0xC program number not used
Channel Aftertouch 0xD aftertouch value not used
Pitch Bend 0xE pitch value (LSB) pitch value (MSB)