Qu'est ce qu'une séquence MIDI ?

MIDI Files: Structure and Information Flow Overview

The information contained in a MIDI file (or MIDI sequence) is transmitted:

FROM: A transmitter (software/sequencer/DAW, keyboard, pad controller, etc.)

TO: A sound generator (sound module, VST/AU plugin, expander, MIDI synthesizer) or any MIDI device that needs synchronization

Information Contained in MIDI Files

1. Who is Playing? (Channel Information)

MIDI supports 16 distinct channels (1-16)

Each channel can represent a different instrument or sound source

Channel assignments allow multiple instruments to be controlled simultaneously

2. At What Tempo? (Timing Information)

Tempo markers specify beats per minute (BPM)

Time signature information (4/4, 3/4, etc.)

MIDI clock signals for synchronization between devices

Timing resolution (ticks per quarter note)

3. With Which Sound? (Program/Patch Information)

Program Change messages to select specific sounds/patches

Bank Select messages to access extended sound libraries

General MIDI (GM) standardized program numbers for common instruments

Sound parameter controls via Control Change messages

4. When? (Event Timing)

Absolute time positions for each event

Quantization information (how strictly events align to the grid)

SMPTE time code for synchronization with video/external devices

Markers and cue points for navigation

5. With Which Notes and How? (Note Information)

Note number (pitch from 0-127, where 60 = middle C)

Velocity data (how hard a note is struck, from 1-127)

Articulation information via Control Change messages

Pitch bend data for expressive pitch variations

6. For How Long? (Duration Information)

Note-On and Note-Off events define duration

Sustain pedal information

Release velocity (how quickly a key is released)

Legato and staccato indications

7. Additional Control Options

Modulation wheel data

Expression controls

Effects parameters (reverb, chorus, etc.)

Aftertouch (pressure applied after striking a key)

System Exclusive (SysEx) messages for device-specific functions

Controller automation data

MIDI Machine Control (MMC) for transport functions

MIDI Show Control (MSC) for theatrical applications

Mixer automation data (volume, pan, etc.)

Loop points and repeat instructions

MIDI files serve as a compact and versatile format for storing musical performance data without the audio itself, making them ideal for editing, arranging, and transferring musical ideas between different systems and devices.