Is there any id which links a saved image file to a video?

[xj25vm]

I've written a glue script in Python to add secondary object detection using Yolov8 to Motion. The script continuously loops over saved jpegs and processes them. I am struggling to find a way to link these jpegs against the saved movie file they would correspond to. I used to include the event_id (%v) in the jpeg name and use this, not realising that event_id's don't correspond to a single movie file, and can span several of them. One option which crossed my mind might be a separate movie_id, which could be exposed to on_picture_save and on_movie_end - but I don't know how doable this might be? Or any other way to make the logical link between a saved picture/jpeg and which saved movie this corresponds to?