Outputs

Last updated 5 August 2026
Outputs represent sinks for media (audio and video).

Video outputs can be split — to feed an external quadrant splitter, or to address specific rectangles on an LED controller — and grouped, when several outputs together carry one large image.

Audio outputs always have an internal output mixer, created automatically with the same name as the output. For custom mixes or mixdowns, create a matrix or ambisonic mixer.

Creating an output here does not put anything on it. The connection between displays, projectors and mixers and their outputs is made in the Routing Windows. Outputs created here appear there — and all available GPU outputs always appear in video routing, whether or not anything is routed to them.

Output types

Type

Sends to

GPU

A physical display port on the server. Detected automatically at startup — these are not created by hand

Audio Output

An audio device and channel set, with its own output mixer

Audio Mixer

A matrix or ambisonic mixer, for custom mixes and mixdowns

NDI

The network, as an NDI stream other machines can receive

DeckLink

SDI or HDMI out through a Blackmagic Design card

Shared Memory

Another application on the same machine, through shared memory

Shared Texture

Another application on the same machine, as a shared GPU texture

Recording

A file on disk

Artnet

Lighting fixtures over Art-Net, with output pixels mapped to DMX channels

Dummy

Nothing — a placeholder output for building or testing a scene without the hardware present

Settings for the selected output

Selecting an output shows its settings in the Inspector. Which sections appear depends on the output type.

Section

Covers

Properties

Resolution, bit depth, refresh rate and the other basics of this output

Split

Divides the output into regions — Matrix Split for a regular grid, or Custom for named rectangles

Group

Combines this output with others into one larger image

Mesh Warping

Geometric warping of the output image

Blend Mask

The blend applied where this output overlaps another

Mechanical Blending

Compensation for mechanical trim gates in the projector beam

Stereo Output

Stereoscopic output — number of channels and stereo mode

DMX Mapping

For an Art-Net output: which output pixels map to which DMX channels

Monitoring

Watches the output and reports when it stops behaving

Mirror Output Image

Mirrors the image, for rear projection and mirror-mounted projectors

Screenshot

Captures a still of what this output is showing

Test & Debug

Test patterns and diagnostics for this output

Common Mistakes

  • A GPU output is missing — outputs are enumerated at startup. After changing the display layout or emulating an EDID, restart Backstage.

  • An output exists but the screen stays black — creating an output routes nothing to it. Make the connection in Video Routing.

  • The split does not match the hardware — the split here and the configuration in the external splitter or LED controller have to describe the same geometry.

  • Audio plays through the wrong device — each audio output names its own device and channels; the mixer that shares its name is not the same thing as the device.

Routing Windows — connecting displays, projectors and mixers to these outputs

Inspector — where the selected output's settings appear

Use a videosplitter with Backstage (f.e. FX4) — splitting one output across several projectors

Output type reference

Visual Output Default Properties

GPU Output

Audio Output

Audio Mixer

NDI Output

Shared Memory Output

Shared Texture Output

Recording Output

Dummy Output

Screenshot