Module org.deepsymmetry.beatlink

Package org.deepsymmetry.beatlink

A library for synchronizing with beats from Pioneer DJ Link equipment, and finding out details about the tracks that are playing.

Overview and installation instructions are found on the Project page on GitHub.

This top level package provides classes for finding a DJ Link network, watching for devices to appear and disappear on it, and creating a VirtualCdj which can obtain more detailed information about what other players are doing, like their current tempo, pitch, playback state, which player is the current tempo master, and the source and database ID of the currently-loaded rekordbox track. See the CdjStatus class for more details.

The classes in the org.deepsymmetry.beatlink.data package can augment this low-level information with rich details about the track metadata, including album art, cue point locations, beat grid, and waveforms, both the whole-track preview, and full detailed waveform for scrolling through. The MetadataFinder is the main coordinator for obtaining and caching this information, and it keeps track of the track metadata for all tracks loaded on decks, either for current playback, or as hot cues.

The metadata queries are performed with the help of the org.deepsymmetry.beatlink.dbserver package, which knows how to locate and communicate with the database servers running on the players.

For shows in which four players are in use, the dbserver interface cannot be relied on, since we are not able to use a real player number ourselves. The CrateDigger class allows us to still obtain metadata in those situations, by downloading entire rekordbox database export files from the players using their NFSv2 servers, which do not care about player numbers. By parsing the database it can also find and download the files containing track analysis information like waveforms, beat grids, artwork, etc.

Background

This project is based on research performed with dysentery, and the protocol analysis resulting from that project.

Raw database access is provided by the Crate Digger project.

An good example of an application built using this library is Beat Link Trigger.

Author:

James Elliott

Interface Summary

Interface	Description
BeatListener	The listener interface for receiving beat announcements.
DeviceAnnouncementListener	The listener interface for receiving device announcements.
DeviceUpdateListener	The listener interface for receiving detailed updates from all devices.
FaderStartListener	The listener interface for receiving fader start commands.
LifecycleListener	The listener interface for receiving updates when a Beat Link component is started or stopped.
MasterHandoffListener	The listener interface for receiving tempo master handoff messages.
MasterListener	The listener interface for receiving updates about changes to tempo master state.
MediaDetailsListener	The listener interface for receiving media detail responses when the VirtualCdj has been told to ask for information about what is in a player’s media slot.
OnAirListener	The listener interface for receiving on-air status messages.
PrecisePositionListener	The listener interface for receiving precise position announcements.
SyncListener	The listener interface for receiving sync control messages.

Class Summary

Class	Description
Beat	A device update that announces the start of a new beat on a DJ Link network.
BeatFinder	Watches for devices to report new beats by broadcasting beat packets on port 50001, and passes them on to registered listeners.
CdjStatus	Represents a status update sent by a CDJ (or perhaps other player) on a DJ Link network.
DeviceAnnouncement	Represents a device announcement seen on a DJ Link network.
DeviceAnnouncementAdapter	An abstract adapter class for receiving device announcements.
DeviceFinder	Watches for devices to report their presence by broadcasting announcement packets on port 50000, and keeps a list of the devices that have been seen, and the network address on which they were seen.
DeviceReference	Uniquely identifies a device on the network.
DeviceUpdate	Represents a device status update seen on a DJ Link network.
LifecycleParticipant	Provides the abstract skeleton for all the classes that can be started and stopped in Beat Link, and for which other classes may have a need to know when they start or stop.
MasterAdapter	An abstract adapter class for receiving updates related to the tempo master.
MediaDetails	Represents information about the media mounted in a player's slot; returned in response to a media query packet.
MixerStatus	Represents a status update sent by a mixer on a DJ Link network.
PlayerSettings	Encapsulates the “My Settings” configuration parameters that can be applied to a player over the network.
PrecisePosition	A device update that reports the exact playback position of a CDJ-3000 (or newer?) player, even if it is not currently playing.
Util	Provides utility functions.
VirtualCdj	Provides the ability to create a virtual CDJ device that can lurk on a DJ Link network and receive packets sent to players, monitoring the detailed state of the other devices.
VirtualRekordbox	Provides the ability to emulate the Rekordbox lighting application which causes devices to share their player state and PSSI (track phrase data).

Enum Summary

Enum	Description
CdjStatus.PlayState1	The possible values of the first play state found in the packet, labeled P1 in the Packet Analysis document.
CdjStatus.PlayState2	The possible values of the second play state found in the packet, labeled P2 in the Packet Analysis document.
CdjStatus.PlayState3	The possible values of the third play state found in the packet, labeled P3 in the Packet Analysis document.
CdjStatus.TrackSourceSlot	The possible values describing from where the track was loaded, labeled Sr in the Packet Analysis document.
CdjStatus.TrackType	The possible values describing the track type, labeled tr in the Packet Analysis document.
PlayerSettings.AutoCueLevel	The options for establishing an automatic cue point when loading a track.
PlayerSettings.AutoLoadMode	The options for whether to autoload hot cues when loading a track.
PlayerSettings.Illumination	The brightness choices for optional illumination (for example of the jog ring or disc slot).
PlayerSettings.JogMode	The options for how the jog wheel affects playback.
PlayerSettings.JogWheelDisplay	The options for what to display in the jog wheel display screens.
PlayerSettings.Language	The options for the player user interface language.
PlayerSettings.LcdBrightness	The brightness options for the player's LCD screen.
PlayerSettings.PadButtonBrightness	The brightness options for the player's performance pads and buttons.
PlayerSettings.PhaseMeterType	The options for the phase meter type.
PlayerSettings.PlayMode	The options for whether to keep playing when a track ends.
PlayerSettings.QuantizeMode	The options the quantization size.
PlayerSettings.TempoRange	The options for tempo range limits.
PlayerSettings.TimeDisplayMode	The options for how time is displayed on the player.
PlayerSettings.Toggle	A standard on/off choice which is used in many settings.
PlayerSettings.VinylSpeedAdjust	The options for the vinyl speed adjust mode.
Util.PacketType	The known packet types used in the protocol, along with the byte values which identify them, and the names by which we describe them, and the port on which they are received.