ISP 3A algorithm behaviour clarification

matthias

Reading on the ColorCamera node API documentation that the ISP does auto-focus, auto-exposure and auto-white-balance and seeing a scene mode like "face priority", I wonder what the camera does exactly when I do not explicitly set auto ROIs for focus and exposure?
Being mainly interested in good stills getting generated for photobooth applications, I am currently having NN based face tracking in the pipeline just to get a ROI for focus+exposure to be applied before the snapshot but wonder if this is actually overkill?
What are the default ROIs/focusing/exposing rules when nothing particular is specified?
Are there any guarantees that possibly pending auto features have been completed at the time a still trigger request is executed?
When can we expect depthai-core to report the status of auto features and ideally focus success/failure?
Thank you!

erik

Hi matthias ,
Regarding first question - 3A is by default done on the whole frame. So ROI would be (0,0,1,1), and your approach seems correct to me for your use-case. There's no guarantee as focus process isn't instant, maybe after focus value doesn't move too much for eg. 10 frames in a row I would send still event, as in that time the lens would have moved to correct position. Thoughts?
Thanks, Erik

matthias

erik Thanks, but AFAIK there there is currently no way to obtain the current focus value via depthai-core?

erik

matthias It's currently in PR, so you could use that branch to obtain focus/iso/exposure time.
Thanks, Erik