First things first – What is a Mezzanine format? A mezzanine format is a mid-rez working copy of your video asset which is of sufficient quality to generate your highest output, but small enough to move around, archive, and work with. The goal is to free up resources once all major edits and processing are completed. The source of your mezzanine format can come from many places. When encoding from a tape with a fully completed asset, the encode can be the mezzanine file. When exporting from a non-linear editor such as Final Cut or Avid, the format chosen as the output can be a mezzanine. The point is, all major editing and processing is completed in the highest format available and this smaller asset can take it from here.
Via Nicolas Weil, Olivier NOEL