Cisco TelePresence MCU 4200 Series

Video cropped around edges on Cisco acquired Codian products

Why is my video cropped around the edges on my Cisco acquired Codian product?

Whenever transmitted video changes aspect ratio some information is lost. In order to fit into a different aspect ratio, for example sending 4:3 video down a 16:9 channel, either the video must be shrunk and have black bars added, or the video must be cropped at the edges.

When Cisco TelePresence MCUs translate between different aspect ratios they choose to crop the image instead of adding black bars. This prevents video images being shrunk, and stops black bars appearing in the middle of the screen in continuous presence (Hollywood squares style) layouts.

In order to reduce cropping, minimize translations between different aspect ratios. For example, if an endpoint is sending a 4:3 video stream to the MCU, then set the MCU to send a 4:3 video stream to other participants of the conference. This can be set globally: go to Settings > Conferences and for Transmitted video resolutions select the appropriate setting. The Transmitted video resolutions can also be set for individual calls when calling out from the MCU in the Add participants page, or for incoming calls by configuring the same field for a configured endpoint.

When cascading between MCUs, check that the link between the MCUs is set to the same aspect ratio as is used by the participants. This can be chosen using the Transmitted video resolutions as described above.

Note that streaming windows are always 4:3 and therefore will always crop 16:9 video streams.

This article applies to the following products:

  • Cisco TelePresence MCU 4200 / MSE 8420
  • Cisco TelePresence MCU 4500

May 3rd, 2011 TAA_KB_193