Streamed properties

A client subscribed to the Components or AudioMixer WebSocket channel is sent a PropertyChanged message each time one of the properties below changes, whatever made the change: the property panel, a script, the HTTP API or another WebSocket client.

The message names the property by the name in the Property column. It is also the name /api/setproperty and SetPropertyValueByObjectId take; Label is what the property panel shows. Type is the type of the value: the message's PropertyType carries its full .NET name (System.Int32 for int, the enum's full name for an enum) and Value the value as text, with an enum by name and its number in ValueEnum. A Components subscriber is sent no values when it subscribes, only changes, so read the starting value with /api/getproperty and apply the stream on top.

What every input, operator or target inherits is listed once, under the Every sections; after them come each component's own. A component that is not listed streams only what every component of its kind does. /api/types/schema reports the same for each property of a type (webSocketChannel, webSocketThrottleFrames), so a client can also ask Composer.

Composer also streams a few properties for its own use, the audio level meters among them. They are internal and not listed here. The exception is an input's or target's running state, RunningIndicatorState, which belongs to its status indicator; it is described with the expected state under Component state. The Switcher channel carries a fixed set of switcher properties of its own, described under Subscription channels.

Notes

• Read-only — the property cannot be set over the API. The message carries CanWrite: false.
• Not in the property panel — the component's property panel does not show it. The audio ones are in the audio mixer.
• Throttled — sent only on some frames; see Throttling.

Throttling

A throttled property is one that can change on every frame, such as a playback position or a gain-reduction reading. Composer sends a change to it only when the change falls on every n-th frame of its output, n being the interval in the Notes column. A change on any other frame is dropped, not delayed.

For a value that changes every frame, that only lowers the rate. For one that changes now and then, the stream can miss a change and show the previous value until the next change that lands on a sent frame. When the exact current value matters, read it with /api/getproperty.

The WebSocketThrottledPropertiesFrequency setting replaces every throttled property's interval with its own when it is set to anything but Default.

Every input

Every input streams these, whatever its type. The AudioMixer ones are its channel strip in the audio mixer, so they change only on an input that carries audio.

Every target

Every target streams these, whatever its type.

Inputs

Audio file input

Cav file input

Replay Channel

SRT input

SRT input 16 channel audio

Seamless audio file input

Switcher

Video File Input

Operators

Compressor V2

Roulette Wheel Tracker V2

Wheel Tracker

Targets

Replay Recorder Target