On Thu, Mar 1, 2018 at 7:14 PM, Shunqian Zheng <zhengsq@xxxxxxxxxxxxxx> wrote: > Hi Tomasz, > > > On 2018年03月01日 16:53, Tomasz Figa wrote: >> >> Hi Shunqian, >> >> On Thu, Mar 1, 2018 at 5:44 PM, Shunqian Zheng <zhengsq@xxxxxxxxxxxxxx> >> wrote: >>> >>> Update the register 0x3503 to use 'no delay latch' for gain. >>> This makes sensor to output the first frame as normal rather >>> than a very dark one. >> >> I'm not 100% sure on how this setting works, but wouldn't it mean that >> setting the gain mid-frame would result in half of the frame having >> old gain and another half new? Depending how this works, perhaps we >> should set this during initial register settings, but reset after >> streaming starts? > > Thank you. > > I'm not quite sure too. Then I try to change gain during capture by: > capture_10_frames.sh & while sleep .01; do v4l2-ctl -d /dev/video4 > --set-ctrl=analogue_gain=54; sleep .01; v4l2-ctl -d /dev/video4 > --set-ctrl=analogue_gain=1024; done > > The gain setting takes effect for every single frame, not in mid-frame from > my test. Alright. I wasn't able to confirm the exact meaning of this bit myself unfortunately, but if that's the behavior you're seeing, we should be fine. Reviewed-by: Tomasz Figa <tfiga@xxxxxxxxxxxx> Best regards, Tomasz
