What is picture lock meaning?

Picture lock is a term used in the post-production phase of filmmaking which means that the edit of the film is considered final and all cuts have been approved by the director and producers. The term refers to the locking of the picture edit, meaning that no further changes to the footage or the editing can be made. This is done before the final color grading, sound mixing, and other post-production work is done. Once picture lock is achieved, the film is considered ready for distribution.