Polycom PVX User Manual

Configuring Video and Audio
Devices for Use with Polycom PVX

You can select from a number of different audio and video input devices to use
with your Polycom® PVX™ application, version 8.0.1 or later.

This document lists the advantages and disadvantages of various devices so you
can choose the correct one for your environment. It also describes the factors you
should consider when selecting a video input device.

Once you have selected your audio and video devices, you need to configure
them for optimum performance. This document describes how to use the PVX
user interface to specify the audio and video device settings. If you plan on using
PVX with the Computer Calling Kit for SoundStation2™ and
SoundStation2W™, this document also describes how to configure the PVX
settings for use with this kit.

The final section of this document provides information on how to resolve audio
and video issues.

Choosing and Configuring Video Input Devices

Polycom PVX supports a wide variety of video input devices. The quality of your
PVX video largely depends on the quality and design of your video input device.
These common devices have been tested with Polycom PVX version 8.0.1 or later:

• AVerMedia AVerTV GO 007 FM Plus PCI

• Creative WebCam Live! Motion

• Creative WebCam Live! Pro

• GlobalMedia iREZ KD 1394

• GlobalMedia iREZ K2 USB 2.0

• Logitech QuickCam Pro 4000

• LogiTech QuickCam for Notebooks Pro

• Logitech QuickCam Pro 5000

• Logitech QuickCam Fusion

• Logitech QuickCam Orbit MP

• Veo Velocity Connect

• V-Stream TV2800 (V-Stream Xpert DVD Maker USB 2.0)

July 2006
3725-22724-003/A

Selecting Audio and Video Devices for Use with Polycom PVX

Determining the CPU Load for Your System

Polycom PVX is a CPU-intensive application. It was originally designed to
accommodate the CPU requirements of third-party video capture devices, so
that the total CPU load results in acceptable performance. As modern devices
have become more capable in resolution and supported features, they have
sometimes also become more CPU intensive. Using some of these devices can
cause the total CPU load to surpass optimal levels. For these CPU-intensive
devices, you can adjust the PVX CPU requirements to accommodate the
device’s requirements.

The following table lists the CPU load levels for some of the video input
devices supported by PVX. You will need this information to configure your
device. If your input device is not listed here, refer to the information which
follows this table.

This device...

AVerMedia AVerTV GO 007 FM Plus PCI Low
Creative WebCam Live! Motion High

Uses this CPU load
level...

Creative WebCam Live! Pro Medium
GlobalMedia iREZ KD 1394 Low
GlobalMedia iREZ K2 USB 2.0

Note that the GlobalMedia iREZ K2 USB 2.0 camera was
tested using quality setting B (the default setting). Higher
quality settings offer additional image processing capability,
but the increased load on the CPU may adversely affect
system performance.

Logitech QuickCam for Notebooks
Pro

Logitech QuickCam Pro 4000 Driver version 7.3.0 Low

Logitech QuickCam Pro 5000 Driver version 9.0.2 Low
Logitech QuickCam Fusion

Note that, as of driver version

9.0.2, the Logitech QuickCam
Fusion audio echo canceller
appears to add delay and
introduce audible artifacts into the
audio.

P/N 961398-04030
Driver version 9.5.0

P/N 961240-04030
Driver version 8.4.1

Driver version 8.4.8 Low
Driver version 9.0.2 Medium

Driver version 9.0.2 Medium

Medium

High

Medium

Note: If the Logitech
Audio Echo
Canceller (AEC) is
enabled, select
High.

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Selecting Audio and Video Devices for Use with Polycom PVX

This device...

Logitech QuickCam Orbit MP Driver version 9.0.2 Medium
Veo Velocity Connect Medium
V-Stream TV2800 (V-Stream Xpert DVD Maker USB 2.0) Low

If your device is not listed, you can calculate the CPU load level yourself.

To determine your video input device’s CPU load:

1. With no other applications running, start Polycom PVX. Make sure that

there is no call in progress and that you can see video.

2. Right-click an empty area in the Windows Task Bar, and choose Task

Manager.

3. Click the Performance tab, and make a note of the CPU Usage, expressed

as a percentage of the total CPU.

4. To determine the CPU usage in MHz, multiply the system’s CPU speed

by the CPU Usage.

Uses this CPU load
level...

5. Use this table to determine the level of CPU usage:

CPU Load

CPU Usage

< 200 MHz Low The device’s driver load is equivalent to the load

200 - 600 MHz Medium Newer devices that support VGA resolutions and

> 600 MHz High The device is using CPU-intensive features, such

Level Description

for devices supported in earlier versions of PVX.
For example: A webcam that captures 320 x 240

video or a PCI video capture card.

higher usually compress the video. The device
drivers must then decode the video before
sending it to PVX, which increases the CPU load.

For example: A webcam that captures 640 x 480
at 30 fps or a DV input device, such as a digital
camcorder or webcam that supports Firewire
IEEE-1394.

as face tracking, video special effects, wide-angle
lens distortion correction, or audio echo
cancellation.

/

For example, suppose your 2.8 GHz computer is running at just over 25% of
the CPU with no call in progress. Determine the CPU load level as follows:

2.8 GHz x 25% = 700 MHz of CPU resources in use

Referring to the table, you see that the camera driver’s load is High.

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Selecting Audio and Video Devices for Use with Polycom PVX

Specifying Advanced Video Properties

To optimize the video from your PVX, you need to correctly specify the PVX
video settings. Before you start, you need to know the CPU load level of your
video input device. Refer to Determining the CPU Load for Your System for
more information.

To specify the advanced video properties:

1. From the PVX Main page, select Setup > Video > Advanced.

2. Configure these settings:

Setting Description
Enable VGA People

Encoding

Video Quality Select Smoother Motion to make video motion

Enable VGA 30 frames
per second

Select if your computer uses less than 15% of the
CPU when PVX is running and no call is in progress.

Clear if your computer uses more than 15% of the
CPU while not in a call.

appear smooth, even though the picture may lose
detail. Select this option when the call includes
participants moving around the room and no shared
documents.

Select Sharper Image for a sharp, clear picture, even
though the motion may not be as smooth. Select this
option when all participants are seated and you need
to show slides or another type of document during the
call.

Clear this setting in most cases.
Select if your device can support VGA at 30 frames

per second while maintaining a low CPU load. Most
cameras are not capable of doing this. Supported
video input devices with this capability include:

• PCI video capture cards

• AVerMedia AVerTV GO 007 FM Plus PCI

• GlobalMedia iREZ K2 USB 2.0

• V-Stream TV2800 (V-Stream Xpert DVD Maker

USB 2.0)

For the camera you
have selected, specify
the camera driver’s
load on the system

Select Low if the device’s driver has little impact on
the total CPU load.

Select Medium if the device’s driver moderately
increases the CPU load.

Select High if the device’s driver significantly
increases the CPU load.

Refer to Determining the CPU Load for Your System
for more information.

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