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3. Split Essence Synchronisation

Aim: Synchronise TDS 3 with TDS 4

Split Essence Synchronisation

Scenario

In order to permit synchronisation of TDS 3 with TDS 4 in an automated fashion, it must be possible to relate them to each other.

Behaviour & Options

In (1), three options were presented for the production of Time Values for TDS 3.

  1. TDS 3's Time Values have no recorded relationship to TDS 1 and TDS 2.

  2. TDS 3's Time Values can be related to corresponding Data Objects in TDS 1 and TDS 2 via a fixed time offset advertised by the mixer (link scoped timing).

  3. TDS 3's Time Values exactly match the Time Values used in TDS 1 and TDS 2 where corresponding Data Objects occur (end to end timing).

Assuming TDS 4 is created in the same Time Context as TDS 1 and TDS 2, it should be clear that option 1 is inappropriate.

Both options 2 and 3 provide potential means of achieving synchronisation, with the following key differences:

  1. The time offsets introduced by each processing device in the chain must be identified. The sum of these offsets for a given chain (for example the audio chain) must then be used to delay the output in corresponding chains (for example the video chain) to ensure the same level of delay is applied prior to the output device.

  2. The offset between the incoming TDS Time Values and the current wall clock time must be identified at each output device (speaker and display). The largest of these values must then be set into all output devices to ensure they all delay the output of Data Objects by the appropriate time.