Switching images on screen – Vision Mixing

A vision mixer or switcher is a device used to select between several different video sources and in some cases compositing (mix) video sources together to create special effects. This is similar to what a mixing console does for audio.

When presenting on stage, a speaker generally runs the presentation of a laptop either from stage or operations in the back of the room.  More often than not the speaker may have a video to show and wants it to run seamlessly, following on from the previous slide and without the need to open a file live in front of an audience.  In order to do this vision mixing is required from the ops booth using a vision mixer, enabling a smooth transition between the laptop on stage and the laptop in the ops booth that has already loaded up the video. This is the same process if a holding slide is to be used on the screens while the presenter takes a break.

Vision Mixing is commonly used where a camera films a live event and the presenter switches between the presentation and a live demonstration on stage, whether it be a panel discussion, or flip chart drawing. Ensuring the smooth transition from the speakers laptop to a live demonstration is not only professional but enhances audience participation as it is constantly engaging.