There are several occasions where quantization can lead to visible
effects.
In WDR mode it can happen that exposure times get set to very low values
(Sometimes 2-3 lines). This intentionally introduced underexposure is
corrected by the GWDR module. As exposure time is quantized by lines,
the smallest possible change in exposure time now results in a quite
visible change in perceived brightness.
On some sensors the possible gain steps are also quite large leading to
visible jumps if e.g. if the exposure time is fixed.
Mitigate that by applying a global gain to account for the error
introduced by the exposure quantization.
ToDo: This needs perfect frame synchronous control of the sensor to work
properly which is not guaranteed in all cases. It still improves the
behavior with the current regulation and can easily be skipped, be
removing the compress algorithm from the tuning file.
Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
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