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HD Player Chapter 6: Timecode
44 Rev. 6.4
Chapter 6: Timecode
Large control systems often require a number of different, and usually diverse, pieces of equipment to operate
within strict timing constraints. For example, an exhibit may use a video display with an associated multi-channel
audio playback system. A method is required to ensure that the audio playback matches the video display. This is
often referred to as “Lip Sync”.
This synchronization problem can be solved using a Timecode signal. Timecode, as the name suggests, is a stream
of coded time stamps encapsulated in an audio signal. The frequency of these time stamps is designed to match
video rates for the various video standards in use around the world. There are three common standards in use
today.
SMPTE - The SMPTE standard is used in the USA and matches the video rate of 29.97 frames per second.
EBU – This standard matches the PAL specification in use in the United Kingdom, i.e. 25 frames per second.
FILM – This standard matches the 24 frames per second used in the motion picture industry.
A typical timecode based system will incorporate a device that generates the timecode for the system, referred to
as the master timecode. This signal is distributed to each timecode aware device in the system. These are often
referred to as slaves. A slave will usually have the ability to generate its’ output based on the timecode it receives.
For example a lighting system could be programmed to generate a lighting scene or effect when a certain timecode
is received.
The MediaSonic HD Player can operate either as a slave or as a master. This allows for maximum flexibility
when integrating the Player in a system. It is even possible for some clips to operate in the master mode while
others operate in the slave mode.
Note: Drop Frame timecode is not supported.
Configuring as a Timecode Master
In the master mode the HD Player is programmed to generate timecode when an MPEG clip begins playing. This
allows any slave devices to be locked to the video output from the Player. Each clip can have it’s own unique
timecode and has the ability to generate a pre-roll and/or run-on option.
The Timecode configuration dialog
To access the timecode configuration dialog:
1. Right click over an entry in the clip list
2. Select “Clip Properties” from the drop down menu.
3. Select the Generate option in the properties to set the parameters.