User`s guide

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3: System Configuration
Configuring Device Interfaces
A device file contains variables called controls that map device register settings or
establish settings for SGI Media Server interaction with peripheral control systems, such
as the Harris Automation ADC100. The controls consist of name-value pairs. The device
register settings establish specific behaviors, such as the compression format for video
ingestion. Exactly one device file exists for each active media processing device in the
SGI Media Server infrastructure.
Configuring Audio and Video Devices in Your System
The directory /usr/vtr/config/device-defaults contains the device files
corresponding to the media devices. Each device or device type has one file; the directory
device-defaults can contain the following files:
MFCODEC For behavior common to all connected multiformat codec (MFCODEC)
media devices
MFCODEC_n For PCI-VIDAUD-MSB-B boards and MSB-REARPANEL-B panels
dq or dq_n For Diaquest software to control external VTRs
Setting Device Parameters
The Video Server Technology (VST) controls are detailed in the vst-controls(5) man
page. There are numerous controls for establishing device behavior. For example, for the
first MFCODEC device, create a file under /usr/vtr/config/device-defaults
called MFCODEC_0. The following shows an example of the file’s contents:
vtr.media.video.input.compression.type mpeg2
vtr.media.mpeg.bit_rate 50000000
vtr.media.video.input.vitc.line_offset 14
vtr.media.clip.start.mode vitc
vtr.media.audio.input.channels 1
vtr.media.audio.input.channel_map.source “A”
vtr.media.audio.input.channel_map.channel_pair “1”
This example device-defaults file sets the default control values for any units
created using the MFCODEC_0 port. The example specifies the following:
• Clip recording with MPEG-2 compression at 50 megabits/second