DDP Viewer

DDP Viewer turns your phone, tablet, or Android device into a live virtual LED
display. It listens for DDP (Distributed Display Protocol) pixel data on your
local network and renders it on screen in real time — no physical controllers,
no wiring, and no LEDs required.

Point any DDP sender — xLights, FPP (Falcon Player), pixel mapper tools, or your
own software — at the device running DDP Viewer and watch your layout light up
instantly.

WHY USE IT
• Preview your sequences and effects without setting up real hardware.
• Test a model or universe on the couch before deploying it to the yard.
• Debug your DDP output: confirm color order, channel mapping, and frame rate.
• Use a spare phone or tablet as a dedicated effects monitor.

LIVE DDP RECEIVER
Listens on UDP port 4048 and reassembles incoming packets into complete frames.
Rendering is decoupled from packet arrival, so the picture stays smooth and
flicker-free no matter how a sender chunks frames or uses the PUSH flag.

TWO LAYOUT MODES
• Matrix — define a simple width × height pixel grid right in the app.
• xModel — import an xLights .xmodel Custom model file to render its exact pixel
grid, including sparse and irregular layouts.

GET THE COLORS RIGHT
Configurable color order — RGB, GRB, BGR, RBG, GBR, or BRG — so WS2812 strips
(usually GRB) and every other device display with accurate colors.

FLEXIBLE CHANNEL MAPPING
Set a channel offset to start reading at any channel, perfect for viewing a
single model inside a larger universe.

LIVE STATS OVERLAY
See FPS, packets per second, the last sequence number, displayed pixel count,
and the source IP of the most recent datagram — everything you need to verify
your stream at a glance.

BUILT-IN TEST PATTERN
No sender on the network? Toggle the animated rainbow test pattern to drive the
canvas locally and confirm your layout renders correctly.

GETTING STARTED
1. Open DDP Viewer and configure your layout (Matrix or import an .xmodel).
2. Find the device's IP address (shown in the app / your network settings).
3. From your DDP sender, send pixel data to that IP on port 4048.
4. Watch it light up.

DDP Viewer is built for the holiday-lights, pixel-art, and LED hobbyist
community. It's a viewer and diagnostic tool — it does not control physical
hardware, so it's completely safe to experiment with.

Open source. No ads. No accounts. No tracking.