Another question from a beginner

[JBR]

I'm very impressed with the quality of these recordings (though I've only done it in daylight so far), but I notice that for every minute of recording it seems to provide four files: FH, FL, RH and RL, which I assume are front and rear in both 'high quality' and 'low quality' (though both are very good).
Not quibbling, but why record in both high and low quality? Is there some advantage in having the low quality versions as well?
I'll just add that the pictures are excellent for number-plate details.

 

[JBR]

Please ignore. Problem solved.