How Does Vision Mixing Work?
Vision mixers are conceptually similar to audio mixers. They take multiple input sources, apply any desired effects or processing, and provide one or more outputs.
Most vision mixers are based around the preview bus and the program bus, each of which has it’s own monitor.
- The program bus is the main output feed, i.e. the vision which is being recorded or broadcast. Whichever source is on the program bus is said to be online.
- The preview bus is used to select and preview the source which is about to be put online.
Note: The preview bus does not have to be used — sources can be cut online without being previewing if desired. However the preview is normally necessary for any visual effects such as transitions, as the effect is constructed from the preview and program sources.