What is creting the presentation on the wall, and what is showing it on to the wall? If it is some kind of projector, then that would likely be receiving its input from some other device, which could be split closer to the source as and used as a content input to the codec which would give your far end a better view of the content than that which you may achieve using a camera. However, if you need to get a person who may be presenting in front of something, then a camera may be a better choice (and, as @PJMack said, you can just feed the camera in as content input). A better choice if you are wanting to have presenter cameras would be a different codec (not the basic Room Kit) which supports the Presenter Track feature with an additonal Cisco Camera.
Wayne
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