Sensor Design and Video Codec Design

The “Open Isn’t Enough” conference (= “No Time to Wait 5”) was scheduled at Nederlands Instituut voor Beeld en Geluid in Hilversum, Netherlands, on 8–10 December 2021. Because of the SARS-CoV-2 pandemic, the conference was transitioned into an online one.


The presentation delves into a few aspects of the physics and mathematics of colour filter mosaic and raw data, which have a huge importance in sensor design and – in the presenter’s opinion – should be considered in video codec design as well.

The presenter thinks that giving the choice between regular binary code and Gray code for audio-visual content encoding would be a useful addition to EBML for the FFV1 video codec and the Matroska container. Based on the experiences gathered with the experimental MovIm video codec, he also made suggestions for possible improvements of FFV1 version 4:

  • support of any type of channel, including the colour model Y′COCG and the raw data generated by Bayer-type sensors;
  • support of 1D and 3D LUTs allowing to document in a transparent manner non-standard digitisations, which are often necessary for colour-degraded film reels;
  • revision of the bit stream in order to correct a few incoherencies and to tune the compression algorithm for both compression speed and compression ratio.


  • The presentation’s slides (PDF, 3.0 MB, MD5 = bd86afb2a3de32edfe11c247ec5da099).


Having graduated in both mathematics and computer science, Reto Kromer became involved in audio-visual conservation and restoration thirty-five years ago. He has been running his own preservation company, AV Preservation by, and lecturing at the Bern University of Applied Sciences and the Elías Querejeta Zine Eskola in Donostia (San Sebastián). His current research includes colour spaces, look-up tables and codec programming and emulation. Previously he was head of preservation at the Cinémathèque suisse (the Swiss National Film Archive) as well as a lecturer at the University of Lausanne and the Academy of Fine Arts Vienna. He served as an AMIA board member during four years. His work has seen him honoured with an inaugural Joint Technical Symposium Award.