I have a new SJ8Pro camera with firmware 1.2.9. Why are video files all the same size, despite the different recording length: 1-13 sec. size is 20480kb? From lenght 14-28 sec. size is 40960kb . The same with LRV files. I record with a resolution 1920 x 1080 30fps.
I'm not very familiar with the video encoding, so I'm just guessing: maybe because the video codec packs 13 sec long bunch of frames together? If each sec of a longer video was packed separadedly, then the file would be much large, maybe. And this method backfires in the case of a very short video.