[libcamera-devel] AE -- what is the goal was Re: Software gathering of image statistics for libcamera on Librem 5

[Pavel Machek]

Hi!

> > > If we only need 200 pixels to process, I'd be very happy to see a CPU
> > > based implementation that could be used on 'any' platform without an
> > > ISP.
> >
> > For millipixels, I was using:
> >
> > bright pixel is at least 200/255.
> >
> > too bright pixel is 240/255.
> >
> > I want not more than 8% too bright pixels, and as long as I have that,
> > I'd like at least 1% bright pixels.
> >
> > Is there consensus what the goal of AE should be?
> 
> There are a number of common techniques and features of such
> algorithms. though many vendors do their own thing and may even have
> "secret sauce" so I wouldn't go so far as to say there's any
> consensus. Increasingly sophisticated image analysis techniques like
> face detectors and machine learning are involved, and there is the
> whole question as to how to meter best for HDR too.

Well.. I'd like to play with face detection, but I don't think I have
enough CPU power available for that.

> Raspberry Pi's implementation, for example, I would describe as
> straightforward and not worrying about any of these complications.
> It's documented here:
> https://datasheets.raspberrypi.com/camera/raspberry-pi-camera-guide.pdf
> (section 5.8). If you want something really simple you can do worse
> than use a trivial centre-weighted scheme.

Thanks for the pointer!

Best regards,
								Pavel
-- 
People of Russia, stop Putin before his war on Ukraine escalates.
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