picture lock

picture lock (uncountable)

1. (film) The point at which a film has gone through final editing and will no longer undergo any visual changes.
   • 2017, Patrick Winters, Sound Design for Low & No Budget Films (page 23)

     You should have “picture lock” before the sound work begins. It is possible to begin sound work before picture lock, but additional expense and time may be incurred in re-conforming your audio edits to the newly re-edited picture.