Configuring a Link device - MediaLive

Configuring a Link device

The Link device has properties that control how it behaves when it is streaming. You can set these properties.

Guidelines for changing configuration fields

You can change most fields at any time, including when the device is attached to an active flow or a running channel.

Changing the Availability Zone

You can change the Availability Zone only when the device is attached to a MediaLive input. Typically you change the Availability Zone only when you're deploying it to use it with a new channel. Even if you stop the channel (which automatically stops the device), you can't simply change the Availability Zone. Doing so would probably make the channel inoperable.

Changing the codec for an input

There is no point changing the codec when a device is attached to a MediaLive input. Only one codec (HEVC) is supported.

Changing the codec for a flow

You might want to change the codec when a UHD device is attached to a MediaConnect flow. (Only UHD devices offer a choice of codecs.) To do this, you must first stop the device. Stopping the device has no impact on the flow. The flow remains active, even though it isn't receiving content. Make then change, then restart the device. The flow starts to receive content again.

Managing the codec in multi-use scenarios

You might switch between using a UHD device for a MediaLive input and a MediaConnect flow. But these two usages support different codecs with that device.

  • A MediaLive input only supports AVC with a UHD device.

  • A MediaConnect flow only supports HEVC with a UHD device.

Consider this scenario: you use a UHD device with a MediaConnect flow and set the codec to AVC. You later attach the device to a MediaLive input. When the device starts (and it's connected to an input), MediaLive will automatically change the codec to HEVC in the configuration, and will encode using HEVC.

When you switch back to using the device with a flow, you should check the codec, because it might not be what you expect.

To configure a device

  1. Open the MediaLive console at

  2. In the navigation pane, choose Link input devices. Find the Link that you want. If there are many devices listed, enter part of the name to filter the list.

  3. Choose the hyperlink for the device. The Device details page for this device appears.

  4. Choose Modify then Configure device. Change fields. For details about each field, see the sections after this procedure. Then choose Update.

    MediaLive sends the new values (except for the name) to the devices, so that the device can update itself.

  5. Display the Device details page and take the appropriate action:

    • If the device is not attached to a MediaLive input or a MediaConnect flow, watch for the state of the device to return to Idle. You can now start the channel (which automatically starts the device), or you can start the device and the flow.

    • If the device is currently attached to a MediaLive input or a MediaConnect flow that is active, watch for the state of the device to return to In use. Note that there is no need for you to restart the input or flow.

Configuration fields

Field Description
Name Enter a descriptive nickname for the device, for use only in MediaLive. We recommend that you give the name a prefix (such as hd-) to indicate that this is a Link HD.
Input source Configures the source that Link sends to MediaLive: SDI or HDMI.

If the device usually has only one source, choose Auto. Link will send the only source, or will send the first source that it encounters.

If the device frequently has sources active on both SDI and HDMI, you must specify which source you want the device to send. You must change this value whenever you want to use the other source.

Maximum bitrate

Set a value if you want to throttle the delivery bitrate to MediaLive.

Leave this field blank to let the device determine the bitrate that is best for the network conditions between the device and MediaLive.

Latency Set the device buffer size (latency).

A higher latency value means a longer delay in transmitting from the device to MediaLive, but improved resiliency.

A lower latency value means a shorter delay, but less resiliency.

If you leave this field blank, the service uses the default value.

Default: 1000 ms (HD devices) or 2000 ms (UHD devices).

Minimum: 0 ms. Maximum: 6000 ms.

Availability Zone The Availability Zone (AZ) for the device. This field has an effect only when the device is attached to a MediaLive input. It is ignored when the device is attached to a flow.

You should change the Availability Zone for the device whenever the device needs to belong to a different Availability Zone. Key use cases for changing the Availability Zone are the following:

  • If you want to use the device in a single-pipeline channel with multiple inputs, where several inputs are Availability Zone aware. All the inputs must use the same Availability Zone (or the two Availability Zones, for a standard-class input).

  • If you want to use the device in a standard channel (two pipelines) in order to implement pipeline redundancy.

Codec This field appears only if the device is a UHD device. Choose the codec for the device to use to encode the video that it outputs. The default is HEVC.

If you set this field with a codec that the device usage doesn't support, MediaLive will reset the value to the default codec. Typically, this behavior occurs when you deploy the device in a compliant way and then switch to a deployment where the specified codec isn't supported.