Source capture¶

Source capture settings in Agora are configured in the stream card on the Inputs tab. There the operator defines where the stream is ingested from, how inputs are ordered, and which clustering strategy applies to ingest.

What you configure on the capture page¶

On the capture page the operator can:

• choose the input clustering strategy;
• add a new source;
• edit an existing source;
• remove a source;
• reorder inputs;
• view a short summary for each input.

When multiple inputs are configured, order matters, so the UI lets you move inputs up and down.

Clustering strategy¶

When configuring capture, the operator chooses a clustering strategy:

• cluster ingest;
• double publish;
• twincast.

That choice defines how the platform ingests the signal and behaves when one ingest path fails.

The default is cluster ingest. This is the standard mechanism that ensures an external stream is taken on one of the origin nodes or related capture paths.

In corporate TV, however, cluster ingest is less common than in classic broadcasting or video surveillance, because it assumes a source the system can pull from. Corporate TV more often relies on publish into Agora rather than autonomous pull.

These modes are described in detail on dedicated architecture pages:

• Cluster Ingest;
• Double Publish;
• Twincast.

Supported input types¶

The current Agora UI supports the following input types for a stream:

• publish;
• multicast;
• SRT;
• RTSP;
• HDMI.

Each input type has its own parameter set.

Multicast¶

For multicast you specify:

• IP address;
• port;
• program number, if used.

This input suits receiving a stream over the enterprise IP network.

SRT¶

For SRT in caller mode (Agora initiates the connection) you configure:

• host;
• port;
• passphrase, if the link is protected.

This mode is used for reliable ingest over IP.

SRT in Agora is commonly used in two scenarios:

• pulling a stream from the internet or a remote device when Agora connects to the source;
• receiving a publication when an external encoder publishes into Agora.

If the source publishes over SRT, use publish mode and configure the listening port for SRT.

RTSP¶

For RTSP you set the source URL.

This input is used for cameras, audio encoders, and other IP sources that speak RTSP.

HDMI¶

For HDMI the operator picks a device from the list of available IO devices.

The list shows:

• streamer hostname;
• device name.

If no free HDMI devices are available, the UI reports that separately.

Choosing such a device binds the stream to a specific streamer. For reliability, configure more than one device.

Working with the input list¶

For each input the list shows:

• input type;
• short parameter summary;
• edit actions;
• delete actions;
• reorder controls.

This lets the operator quickly verify ingest configuration and change input priority without editing internal data by hand.

Automatic failover between sources¶

Automatic failover between sources is one of the most important input mechanisms in Agora.

A stream may have several sources sorted by priority. Higher entries are preferred; lower ones act as backup or alternates.

If no frames arrive on the active source within source_timeout, the system switches to the next available source by priority.

That lets you prepare backup playout scenarios without manual operator action.

Example source priorities¶

A typical corporate TV setup:

• first priority: stream publication;
• second priority: external source capture.

Then:

• while publication is present, viewers see the studio feed;
• if studio publication drops and no frames arrive within source_timeout, the system switches to the second source;
• the second source may be a slate, a backup channel, or another prepared feed.

You can run studio live in normal conditions and fall back automatically without operator intervention.

Publish-wait mode¶

In some corporate TV scenarios the source is not fixed up front. The stream is created in publish-wait mode.

In that mode:

• the stream may have no predefined source;
• Agora does not start pull ingest on its own;
• the system waits for an external encoder or app to publish into Agora.

This is typical for studio workflows, software encoders, and one-off events: the operator prepares the stream in the system while actual signal delivery starts only at publish time.