Multi-channel Synchronization

The Makito X multi-channel synchronization feature is designed to work in the broadcast industry where remote producers typically capture multiple views of the same content and transport it over a network to a central production facility. All these channels need to be synchronized to within one frame period at the decoders, so that downstream equipment does not experience replay issues when switching between video and audio sources.

Following is a summary of the steps to configure multi-channel sync on the Makito X encoder and decoder to synchronize content across multiple channels. For additional information, please refer to the Multi-Channel Synchronization Technical Brief (available through the Download Center on the Haivision Support Portal.).

Step 1: NTP

Configure NTP Settings

The source of timecodes must be “NTP locked” on both the Makito X encoder and decoder. You can configure the encoder and the decoder to use NTP (Network Time Protocol) on the (Web interface) Administration> Date and Time page. For the decoder, see Configuring Date and Time.

Note

The Makito X encoder can also pass the timecode from the video signal, so the camera can also be the source. In this case, encoder does not need to be synced to an NTP server, but the cameras do (in order to generate the timecodes).

There are two possible options for multi-channel sync:
Option 1 - The encoder is configured to use “System” timecodes and must be “NTP locked”.
Option 2 - The encoder is configured to use “Video” timecodes; therefore, the video source must generate timecodes which are locked to the same master clock.

Tip

Make sure your devices are configured to use the same fast, precise NTP server. We recommend an offset (difference between local clock and remote clock) of around 5 ms.

Step 2: Encoder

Configure Encoders

On the Video Encoder settings page:

Set the Timecode Source to:
- "System" if the timecodes are to be generated by the encoder.
  -or-
- "Video" if the timecodes are pre-synchronized by the upstream equipment and embedded into the SDI signal.
Start the stream output on all encoders.

Step 3: Decoder Pass 1

Configure Decoders

For each decode channel to be synchronized, on the SDI 1 or SDI 2 Decoder page:

Enable buffering and select MultiSync for the buffering Mode. (See SDI Decoder Settings.)
Initially, enter a value such as the default (1000ms) for the MultiSync Delay (unless SRT is configured, then add the negotiated SRT latency value for the stream).
Start the stream reception on all decoders.

Step 4: Measure (Decoder Pass 2)

Observe Delay Ranges

On the SDI 1 or SDI 2 Decoder page:

Wait 10 to 20 seconds while the decoder starts receiving the stream and gathers statistics.
Either open the Statistics pane or check beside the MultiSync Delay field, and you will see a range of valid multisync values, such as "Min=1,317 ms, Max=3,112 ms".
Note down the min/max ranges for all channels to be synchronized.

Note

A yellow or red triangle is displayed next to the fixed delay box if it is currently outside the acceptable range with a hover tip explaining the problem if it Is out of range.

Tip

If you are synchronizing many decoder channels, complete Step 3 for all of them and then go back to record the range values.

Step 5: Finalize (Decoder Pass 3)

Configure MultiSync Delay

Based on the results of Decoder Pass 2:

Select a single delay value that is in the acceptable range for all of the decoders. Avoid using the minimum or maximum values.
On the SDI 1 or SDI 2 Decoder page, set the MultiSync Delay on all of the decoder channels to the same value.

After a few seconds of playback, all of the decoder channels will be playing in sync with each other.