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/*
* Copyright (C) 2012, BMW AG
*
* This file is part of GENIVI Project AudioManager.
*
* Contributions are licensed to the GENIVI Alliance under one or more
* Contribution License Agreements.
*
* \copyright
* This Source Code Form is subject to the terms of the
* Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with
* this file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* \\author Christian Linke (christian.linke@bmw.de)
*
*/
/*!
\page lip Lipsync
\section t The Task of the Audiomanager
It is the job of the AudioManager to retrieve all latency timing information from each connection, to aggregate this information and provide a latency #
information on a per MainConnection Basis. It is not the task of the AudioManager to actually delay or speed up video or audio signals to achieve a lipsync.
The actual correction shall be done in the with the information provided by the AudioManager.
The time information is always reported by the routingadapters for each connection. Delays that are introduced in a sink or a gateway are counting for the
connection that connects to this sink or gateway.
\section ex Example
\image html delay.jpg
This graph shows how the delay is calculated:
- Connection 1 has a delay 2ms + 60ms that is added due to the gateway
- Connection 2 has a delay 0ms + 10ms due to sink
So the routing adapters report 62ms and 10ms, the audiomanager will add this to 72ms and report this value for the main connection from sink to source.
The videoplayer getting this information can now delay his video against the audio for 72ms and be in perfect lipsync.\n
After the buildup of a connection the first timing information needs to be sent within 5 seconds, the timing information from the routing adapters need to
be sent via 4 seconds. If the latency for a connection is variable and changes over lifetime of the connection, the routing adapters shall resend the value
and the audiomanager will correct the over all latency.
*/
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