Here is a description of these options:

Capture Device: Choose which installed camera or video capture device to use. You can also change settings (brightness, color, that are device driver dependent under Device Settings. Compression: You may choose between H.261 and H.264 software encoders. H.264 provides superior video quality when compared to H.261. But H.264 requires a modern processor. Pentium 4 3GHz or Dual PowerPC G5 are recommended. Sending H.264 video in a meeting is more demanding than receiving from other participants so users running on slower computers can choose to send H.261 video instead. The higher compression rate of H.264 makes it more sensitive to packet loss than H.261.

Requested Bandwidth: This slider lets you adjust the amount of bandwidth to use within the limits permitted by the e-meeting room.

Reducing this value may help if the participants have trouble hearing you because of network overload.

Quality: A lower image quality indicates more compression (more blockiness and lower quality image). A lower image quality will also give higher frame rate. A higher image quality will give a less blocky picture but will result in lower frame rates.

Use Scaling is a Mac only feature. Many Mac cameras only grab in 320 x 240 pixels, instead of the standard CIF (352 x 288), causing a gray frame around the video image. Clicking this feature will scale the image to remove the frame. The feature is only recommended for high-speed dual processor Macs.

Limit Capture Frame Rate: Limits the amount of images captured. This gives a lower frame rate but is recommended for slower computers as it saves processor resources.

Video Follows Audio: Makes the Video window follow the person currently speaking. This can be temporarily overridden by holding down the mouse button while pointing it at a user in the Participants module. (Read more about this feature here)

For this feature to work, Silence Suppression should be used by all participants and only participants that are talking should be using the microphone button.

Lip-Synch. Lip-synch is used to synchronize the video images to the voice of the speaker. If you have a slow computer, un-clicking this option may save resources.

For full lip-synch to be achieved, 300 kilobits of video bandwidth per sender is required.