name	rekordbox-midi-integration
description	Specialist in Rekordbox MIDI Learn integration, including MIDI mapping workflow, CSV file format, Rekordbox function reference, official documentation, and real-world DDJ controller examples. Use when working on Rekordbox MIDI controllers, CSV generation/import/export, function mapping, or debugging Rekordbox MIDI integration.

Rekordbox MIDI Integration Expert

Master Rekordbox MIDI Learn integration for creating compatible controller mappings. This skill provides comprehensive knowledge of Rekordbox's MIDI system, official documentation, CSV structure, complete function reference, MIDI code formats, and real-world examples from Pioneer DDJ controllers.

When to Use This Skill

Understanding Rekordbox MIDI Learn workflow and features
Generating Rekordbox-compatible CSV files
Mapping MIDI controllers to Rekordbox functions
Parsing or validating CSV structure
Looking up Rekordbox function names and categories
Debugging CSV import/export issues
Understanding MIDI code hex format
Implementing deck assignments
Working with control types and options
Referencing official Rekordbox documentation
Learning from real-world DDJ controller mappings
Reviewing MIDI-related code changes

Rekordbox MIDI Learn System Overview

What is MIDI Learn?

Rekordbox MIDI Learn (available in version 4.0.6+) enables free assignment of rekordbox dj (Performance mode) features to MIDI controllable equipment. You can assign functions like Play/Pause, Hot Cue, loops, effects, and browser controls to physical buttons, knobs, faders, and encoders on MIDI controllers.

Key features:

Assign any Rekordbox function to any MIDI control
Modify preset mappings for supported controllers
Create custom mappings for unsupported hardware
Export/import CSV mapping files
LED feedback support for compatible hardware

MIDI Learn Workflow

Connection: Connect MIDI controller via USB to computer
Launch: Open rekordbox in PERFORMANCE mode
MIDI Settings: Click MIDI button (upper right, next to Preferences)
Device Selection: Select connected device from dropdown
Function Assignment:
- Click [ADD] to add function from category tabs
- Click function row, then [LEARN] button
- Operate physical control (button/knob) on hardware
- MIDI code automatically captured in [MIDI IN] column
Testing: Test control sends correct MIDI and triggers function
Export: Click [EXPORT] to save CSV mapping file

MIDI Setting Window Components

Menu bar:

Device selector dropdown
[DEFAULT] - Reset to factory settings
[LEARN] - Enable MIDI learn mode
[ADD] - Add function from category
[DUPLICATE] - Copy function to other decks
[DELETE] - Remove function
[IMPORT] - Load CSV file
[EXPORT] - Save CSV file

Category tabs:

Deck (playback, tempo, loops)
Mixer (faders, EQ, filter)
Browser (track selection, load)
FX (effects units, parameters)
Sampler (sample pads, banks)

MIDI setting columns:

Function: Rekordbox function name
Deck: Deck assignment (1-4, or global)
MIDI IN: 4-digit hex code received from hardware
Type: Control type (Button, Knob, Rotary, etc.)
MIDI OUT: 4-digit hex code sent for LED feedback
Comment: User notes

CSV File Format Specification

File Structure

Rekordbox CSV files have a specific 15-column structure:

@file,1,ControllerName,,,,,,,,,,,,
#name,function,type,input,deck1,deck2,deck3,deck4,output,deck1,deck2,deck3,deck4,option,comment

Column Definitions

#	Column Name	Description	Example
0	#name	Internal identifier (purpose unclear)	`PlayPause`, `#CrossFader`
1	function	Rekordbox function to map (key column)	`PlayPause`, `Browse+Press`
2	type	Control type	`Button`, `Rotary`, `KnobSliderHiRes`
3	input	MIDI IN code (4-digit hex)	`900B`, `B640`
4-7	deck1-4	Input deck channel assignments	`0`, `1`, `2`, `3`
8	output	MIDI OUT code (4-digit hex)	`900B`, `B640`
9-12	deck1-4	Output deck channel assignments	`0`, `1`, `2`, `3`
13	option	Optional flags (semicolon-separated)	`Fast;Priority=50`, `RO`
14	comment	Human description	`Play/Pause`

Note: Column 1 (function) determines the actual mapping. If empty, the row has no functional mapping. See REKORDBOX-MIDI-CSV-SPEC.md for full specification.

Special Rows

@file,1,DDJ-FLX4,,,,,,,,,,,,           # Metadata header
#name,function,type,input,deck1,...   # Column header
,,,,,,,,,,,,,,                          # Empty separator rows
# Browser,,,,,,,,,,,,,,                 # Section comment

MIDI Code Format

4-Digit Hex Format

MIDI codes are represented as 4-digit hexadecimal strings:

[Status Byte][Data Byte]
    ↓           ↓
   90          3C

Status Byte Breakdown

Status Byte = Command Nibble + Channel Nibble

Example: 0x90 = Note On (0x9x) + Channel 1 (0x0)
Example: 0xB6 = Control Change (0xBx) + Channel 7 (0x6)

Common MIDI Commands

Hex	Command	Usage
`9x`	Note On	Buttons, Pads
`8x`	Note Off	Button release
`Bx`	Control Change (CC)	Knobs, Faders, Encoders

Channel Encoding (0-indexed)

Deck	CSV Value	MIDI Channel	Hex Nibble
Deck 1	`0`	Ch 1	`x0`
Deck 2	`1`	Ch 2	`x1`
Deck 3	`2`	Ch 3	`x2`
Deck 4	`3`	Ch 4	`x3`
Global	`6`	Ch 7	`x6`

Note: Rekordbox uses 0-indexed channels internally (0-15), but MIDI convention displays them as 1-16.

MIDI Code Examples

# Button (Note On, Ch 1, Note 0x0B)
900B    → Status: 0x90 (Note On, Ch 0), Data: 0x0B (note 11)

# Knob (CC, Ch 7, CC 0x40)
B640    → Status: 0xB6 (CC, Ch 6), Data: 0x40 (CC 64)

# Rotary (CC, Ch 1, CC 0x00)
B000    → Status: 0xB0 (CC, Ch 0), Data: 0x00 (CC 0)

Control Types

Button and Pad Types

Type	Description	MIDI Message	Use Case
`Button`	Standard button	Note On/Off	Play, Cue, Hot Cue
`Pad`	Velocity-sensitive pad	Note On (with velocity)	Performance pads

Knob and Slider Types

Type	Description	Resolution	Range
`Knob`	Standard knob	7-bit	0-127 (0x00-0x7F)
`KnobSlider`	Standard fader	7-bit	0-127 (0x00-0x7F)
`KnobSliderHiRes`	High-resolution fader	14-bit	0-16383 (0x0000-0x3FFF)

Encoder Types

Type	Description	Behavior
`Rotary`	Rotary encoder	Relative values (64=center, >64=CW, <64=CCW)
`JogRotate`	Jog wheel rotation	Continuous rotation
`JogTouch`	Jog wheel touch	Touch detection
`Difference`	Position difference	Search/seek

Special Types

Type	Description	Use Case
`Indicator`	Output only (no input)	LED feedback
`Value`	Special value input	Needle Search, Velocity Sampler

Rekordbox Function Reference

Deck Functions

Playback Control:

PlayPause - Play/Pause toggle
Cue - Cue point set/play
JumpToTrackStart - Return to start
Sync - Beat sync on/off
Master - Master tempo control

Loop Control:

LoopIn - Set loop in point
LoopOut - Set loop out point
ActiveLoop - Enable/disable active loop
4BeatLoop, 8BeatLoop, 16BeatLoop - Auto-loop sizes
LoopHalf - Halve loop size
LoopDouble - Double loop size

Hot Cues:

HotCue1 through HotCue8 - Hot cue points
PAD1_HotCue through PAD8_HotCue - Performance pad hot cues

Tempo Control:

TempoSlider - Tempo fader
TempoRange - Tempo range selector
BeatJump - Beat jump forward/backward

Jog/Scratch Functions

JogScratch - Scratch mode
JogPitchBend - Pitch bend mode
JogSearch - Track search
JogTouch - Touch detection
WheelPitchBend - Outer wheel pitch bend

Mixer Functions

CrossFader - Crossfader
ChannelFader - Channel volume fader
Gain - Channel gain
HighEQ, MidEQ, LowEQ - 3-band EQ
FilterKnob - Filter control

Browser Functions

Browse - Track/folder selection
Load - Load track to deck
Forward - Open folder
Back - Close folder
RelatedTracks - Related tracks view
SwitchActiveWindow - Toggle browse view

FX Functions

FX1, FX2, FX3 - FX units
FXSelect - FX type selector
FXKnob1, FXKnob2, FXKnob3 - FX parameters
BeatFX - Beat FX toggle

CSV Options Field

Option Flags

Options are semicolon-separated flags in column 13:

# Examples
Fast;Priority=50
Blink=600
RO
Fast;Blink

Common Options

Option	Description	Use Case
`Fast`	High-priority processing	Time-critical controls (tempo, play)
`Priority=N`	Priority level (0-100)	Control processing order
`Blink=N`	Blink rate in milliseconds	LED feedback blink speed
`RO`	Read-Only (output only)	Indicator LEDs, feedback

Deck Assignment Patterns

Per-Deck Assignment

Each function can be assigned to specific decks:

# Deck 1 and 2 only
PlayPause,PlayPause,Button,900B,0,1,,,900B,0,1,,,Fast,Play/Pause
                           ↑   ↑ ↑
                           |   | Deck 2: Ch 2 (0x1)
                           |   Deck 1: Ch 1 (0x0)
                           Input MIDI code

Global Functions

Global functions use channel 6 (Ch 7):

# Browser (not deck-specific)
Browse,Browse,Rotary,B640,,,,,,,,,,,Browse Track Select
                      ↑
                      Ch 7 (global)

Empty Deck Slots

Empty slots indicate the function doesn't apply to that deck:

Load,Load,Button,,9646,9647,,,,,,,,,Load to Deck
              ↑
              Empty = no deck 1 assignment

Parsing Strategy

Header Detection

# Skip metadata
if row[0].startswith('@'):
    continue

# Skip column headers
if row[0].lower() == '#name':
    continue

# Skip empty rows
if not row or not row[0].strip():
    continue

# Skip comment rows
if row[0].startswith('#'):
    continue

MIDI Code Parsing

def parse_midi_code(code: str) -> tuple:
    """
    Parse 4-digit hex MIDI code

    Args:
        code: 4-digit hex string (e.g., '900B')

    Returns:
        (status_byte, data_byte, message_type, channel, note_or_cc)
    """
    if not code or len(code) != 4:
        return None

    status = int(code[:2], 16)  # First 2 digits
    data = int(code[2:], 16)    # Last 2 digits

    command = (status & 0xF0) >> 4  # Upper nibble
    channel = status & 0x0F          # Lower nibble

    # Determine message type
    if command == 0x9:
        msg_type = 'note_on'
    elif command == 0x8:
        msg_type = 'note_off'
    elif command == 0xB:
        msg_type = 'control_change'
    else:
        msg_type = 'unknown'

    return (status, data, msg_type, channel, data)

Deck Channel Extraction

def extract_deck_channels(row) -> list:
    """Extract input deck channel assignments from CSV row"""
    channels = []
    for i in range(4, 8):  # Columns 4-7
        if i < len(row) and row[i].strip():
            try:
                channels.append(int(row[i]))
            except ValueError:
                channels.append(None)
        else:
            channels.append(None)
    return channels

Common Patterns

Standard Button Mapping

PlayPause,PlayPause,Button,900B,0,1,,,900B,0,1,,,Fast;Priority=50,Play/Pause

Function: PlayPause
Type: Button
Input: 900B (Note On, Ch 1, Note 11)
Decks: 1 (Ch 0) and 2 (Ch 1)
Output: Same as input (LED feedback)
Options: Fast processing, Priority 50

Rotary Encoder Mapping

Browse,Browse,Rotary,B640,,,,,,,,,,,Browse Track/Folder

Function: Browse
Type: Rotary
Input: B640 (CC, Ch 7, CC 64)
Decks: Global (no specific deck)
Output: None (no LED feedback)

High-Resolution Fader

TempoSlider,TempoSlider,KnobSliderHiRes,B000,0,1,,,,,,,,Fast,Tempo Control

Function: TempoSlider
Type: KnobSliderHiRes (14-bit resolution)
Input: B000 (CC, Ch 1, CC 0)
Decks: 1 and 2
Options: Fast processing

Validation Rules

Required Fields

FunctionName (column 0): Must not be empty
Type (column 2): Must be valid control type
InputMIDI (column 3): Must be 4-digit hex or empty for indicators
At least one deck assignment OR global assignment

MIDI Code Validation

def validate_midi_code(code: str) -> bool:
    """Validate 4-digit hex MIDI code"""
    if not code:
        return False
    if len(code) != 4:
        return False
    try:
        int(code, 16)  # Must be valid hex
        return True
    except ValueError:
        return False

Control Type Validation

VALID_TYPES = {
    'Button', 'Pad',
    'Knob', 'KnobSlider', 'KnobSliderHiRes',
    'Rotary', 'JogRotate', 'JogTouch', 'Difference',
    'Indicator', 'Value'
}

def validate_control_type(control_type: str) -> bool:
    return control_type in VALID_TYPES

Generation Example

Creating a New Mapping

def generate_csv_row(
    function: str,
    display_name: str,
    control_type: str,
    input_midi: str,
    decks: list,
    output_midi: str = '',
    out_decks: list = None,
    options: str = '',
    comment: str = ''
) -> list:
    """Generate a CSV row for Rekordbox"""

    # Default output to input
    if not output_midi:
        output_midi = input_midi
    if out_decks is None:
        out_decks = decks

    # Pad deck lists to 4 elements
    while len(decks) < 4:
        decks.append('')
    while len(out_decks) < 4:
        out_decks.append('')

    row = [
        function,
        display_name,
        control_type,
        input_midi,
        *[str(d) if d != '' else '' for d in decks[:4]],
        output_midi,
        *[str(d) if d != '' else '' for d in out_decks[:4]],
        options,
        comment
    ]

    return row

# Example usage
row = generate_csv_row(
    function='PlayPause',
    display_name='Play/Pause',
    control_type='Button',
    input_midi='900B',
    decks=[0, 1],  # Deck 1 and 2
    options='Fast;Priority=50',
    comment='Play/Pause toggle'
)

Testing CSV Files

Import Test Procedure

Generate CSV file
Launch Rekordbox (Performance mode)
Click MIDI button (upper right)
Select controller from dropdown
Click IMPORT button
Select generated CSV file
Verify functions appear in MIDI setting list
Test physical controls send correct MIDI

Common Import Errors

"Invalid file format"

Missing @file header
Missing #name header row
Incorrect column count

"MIDI code conflict"

Duplicate MIDI codes for different functions
Same MIDI code assigned multiple times

"Function not recognized"

Invalid function name
Typo in function identifier

Performance Considerations

Fast Processing

Functions marked Fast are prioritized:

Playback controls (Play, Cue)
Tempo controls
Time-critical operations

Priority Levels

Priority=N (0-100) controls processing order:

Higher priority = processed first
Default priority = 50
Use for conflict resolution

Real-World DDJ Controller Examples

DDJ-FLX4 Controller Mapping

The DDJ-FLX4 is an entry-level 2-deck controller with 259 MIDI mappings. Key examples from its CSV:

Browser controls (global, Ch 7):

Browse,Browse,Rotary,B640,,,,,,,,,,,Browse(Track/Folder Select)
Forward,Browse+Press,Button,9641,,,,,,,,,,,Library Forward (Folder Open)
Back,Browse+Press+Shift,Button,9642,,,,,,,,,,,Library Back (Folder Close)
Load,Load,Button,,9646,9647,,,,,,,,,Load to Deck / Instant Double (double click)

Playback controls (Deck 1 & 2):

PlayPause,PlayPause,Button,900B,0,1,,,900B,0,1,,,Fast;Priority=50,Play/Pause
Cue,Cue,Button,900C,0,1,,,900C,0,1,,,Fast;Priority=50,Cue Set/Play Cue Back
JumpToTrackStart,Cue+Shift,Button,9048,0,1,,,9048,0,1,,,Fast;Priority=50,Jump to track start

Jog wheel (complex control types):

JogScratch,JogScratch,JogRotate,B022,0,1,,,,,,,,RO,Scratch
JogPitchBend,JogPitchBend,JogRotate,B023,0,1,,,,,,,,RO,Pitch Bend
JogTouch,JogTouch,JogTouch,9036,0,1,,,,,,,,RO,Touch

High-resolution fader (14-bit):

TempoSlider,TempoSlider,KnobSliderHiRes,B000,0,1,,,,,,,,Fast,Tempo Control
CrossFader,CrossFader,KnobSliderHiRes,B61F,,,,,,,,,,Fast,Crossfader
ChannelFader,ChannelFader,KnobSliderHiRes,B013,0,1,,,,,,,,,CH Fader

Mixer controls:

Gain,Gain,KnobSliderHiRes,B004,0,1,,,,,,,,Fast,Gain
HighEQ,HighEQ,KnobSliderHiRes,B007,0,1,,,,,,,,Fast,High EQ
MidEQ,MidEQ,KnobSliderHiRes,B00B,0,1,,,,,,,,Fast,Mid EQ
LowEQ,LowEQ,KnobSliderHiRes,B00F,0,1,,,,,,,,Fast,Low EQ

DDJ-FLX10 Controller Mapping

The DDJ-FLX10 is a professional 4-deck controller with 567 MIDI mappings. Notable features:

4-deck support:

PlayPause,PlayPause,Button,900B,0,1,2,3,900B,0,1,2,3,Fast;Priority=50;Dual,Play/Pause
Cue,Cue,Button,900C,0,1,2,3,900C,0,1,2,3,Fast;Priority=50;Dual,Cue Set/Play Cue Back
Sync,Sync,Button,9058,0,1,2,3,9058,0,1,2,3,Blink=600;Dual,Sync On/Off

Advanced loop controls:

LoopIn,LoopIn,Button,9010,0,1,2,3,9010,0,1,2,3,Dual;Fast,Loop in/Loop in adjust
LoopOut,LoopOut,Button,9011,0,1,2,3,9011,0,1,2,3,Dual;Fast,Loop out/Loop out adjust
LoopHalf,LoopIn,Button,9012,0,1,2,3,9012,0,1,2,3,Dual;Fast,Loop Size Select (Half)
LoopDouble,LoopOut,Button,9013,0,1,2,3,9013,0,1,2,3,Dual;Fast,Loop Size Select (Double)
4BeatLoop,4BeatLoop,Button,9014,0,1,2,3,9014,0,1,2,3,Dual;Fast,Auto Loop On/Off

Key Sync features:

KeySync,KeySync,Button,9065,0,1,2,3,9065,0,1,2,3,Dual,Key Sync On/Off
MasterTempo,KeySync+LongPress,Button,901A,0,1,2,3,901A,0,1,2,3,Dual,MasterTempo On/Off
KeyReset,KeySync+Shift,Button,9064,0,1,2,3,9064,0,1,2,3,Dual,Key Reset

Special options:

Dual - Dual deck mode for 4-deck controllers
Fast;Priority=50 - High-priority time-critical controls
Blink=600 - LED blink rate in milliseconds
RO - Read-Only (output/indicator only)

Common DDJ Mapping Patterns

Pattern 1: Shift button modifiers

# Primary function
PlayPause,PlayPause,Button,900B,0,1,,,900B,0,1,,,Fast;Priority=50,Play/Pause
# Shift+function variant
PlayPause,PlayPause+Shift,Button,900E,0,1,,,900E,0,1,,,Fast;Priority=50,Play/Pause

Pattern 2: Load with multi-deck support

# Empty first deck column means no deck 1 assignment
Load,Load,Button,,9646,9647,,,,,,,,,Load to Deck

Pattern 3: Global browser controls

# Empty deck columns, global channel (6 = Ch 7)
Browse,Browse,Rotary,B640,,,,,,,,,,,Browse Track Select

Pattern 4: Jog wheel with RO (output only)

# No MIDI OUT, RO option
JogScratch,JogScratch,JogRotate,B022,0,1,,,,,,,,RO,Scratch

Complete Rekordbox Function Reference

Official Function List (from RB_CSV_6.7.4.xml)

Playback Functions:

PlayPause - Play/Pause toggle (type: Button)
Cue - Cue point set/play (type: Button)
JumpToTrackStart - Return to track start (type: Button)
TrackNext - Next track (type: Button)
TrackPrev - Previous track (type: Button)
SearchFwd - Search forward (type: Button)
SearchRev - Search reverse (type: Button)
NeedleSearch - Position search (type: Value)
Slip - Slip mode (type: Button)
Quantize - Quantize on/off (type: Button)
Reverse - Reverse playback (type: Button)
SlipReverse - Slip reverse (type: Button)
Vinyl - Vinyl mode (type: Button)
AutoCue - Auto cue (type: Button)

Tempo Functions:

TempoSlider - Tempo fader (type: Knob/Fader)
TempoRange - Tempo range selector (type: Button)
TempoReset - Reset tempo to 0% (type: Button)
Sync - Beat sync on/off (type: Button)
SyncRate - Sync rate (type: Button)
Master - Master tempo control (type: Button)
TapBpm - Tap tempo (type: Button)
MasterTempo - Master tempo on/off (type: Button)
PitchBendUp - Pitch bend up (type: Button)
PitchBendDown - Pitch bend down (type: Button)

Loop Functions:

LoopIn - Set loop in point (type: Button)
LoopOut - Set loop out point (type: Button)
ActiveLoop - Enable/disable active loop (type: Button)
LoopHalf - Halve loop size (type: Button)
LoopDouble - Double loop size (type: Button)
LoopHalfDouble - Loop size adjust (type: Rotary)
LoopMove - Move loop (type: Rotary)
LoopMoveRight - Move loop right (type: Button)
LoopMoveLeft - Move loop left (type: Button)
ReloopExit - Reloop/exit (type: Button)
ReTrigger - Loop retrigger (type: Button)
4BeatLoop - 4-beat auto loop (type: Button)
AutoLoop - Auto loop on/off (type: Button)
Beat loop sizes: BeatLoop1_64, BeatLoop1_32, BeatLoop1_16, BeatLoop1_8, BeatLoop1_4, BeatLoop1_2, BeatLoop1, BeatLoop2, BeatLoop4, BeatLoop8, BeatLoop16, BeatLoop32, BeatLoop64, BeatLoop128, BeatLoop256, BeatLoop512

Key Shift Functions:

SemitoneUp - Semitone up (type: Button)
SemitoneDown - Semitone down (type: Button)
KeySync - Key sync (type: Button)
KeyReset - Reset key (type: Button)

Grid Functions:

GridAdjust - Grid adjust (type: Button)
GridSlide - Grid slide (type: Button)
GridAdjustHalf - Grid adjust half (type: Button)
GridAdjustDouble - Grid adjust double (type: Button)

DVS Functions:

DvsAbsolute - DVS absolute mode (type: Button)
DvsRelative - DVS relative mode (type: Button)
DvsInternal - DVS internal mode (type: Button)
DvsThrough - DVS through mode (type: Button)
DvsAbsRelInt - DVS mode toggle (type: Button)

Track Separation Functions:

ActivePartInst - Instrumental stem (type: Button)
ActivePartVocal - Vocal stem (type: Button)
ActivePartDrums - Drums stem (type: Button)

Capture:

SlicerCapture - Slicer capture (type: Button)

Function Type Reference

Type codes from RB_CSV_6.7.4.xml:

type="1" - Button/Pad
type="2" - Rotary encoder (relative values)
type="3" - Knob/Fader (absolute values)
type="5" - Indicator (output only)
type="7" - Value (special input like NeedleSearch)

References

Project Documentation:

REKORDBOX-MIDI-CSV-SPEC.md - Community specification (reverse-engineered)
references/Rekordbox_MIDI_Learn_Guide_v5.3.0.pdf - Official MIDI Learn operation guide

Controller CSV Examples:

references/DDJ-FLX10.midi.csv - Professional 4-deck controller (567 mappings)
references/DDJ-GRV6.midi.csv - 2-channel controller (339 mappings)

Implementation:

sniffer.py - MIDI sniffer with CSV parser (class RekordboxCSVParser)

External Sources:

Rekordbox installation: /Applications/rekordbox 7/rekordbox.app/Contents/Resources/MidiMappings/

Install Skill

SKILL.md