Hi Kim, On Wed, 2009-03-18 at 13:32 +0900, Dongsoo, Nathaniel Kim wrote: > Hello, > > I accidently realized today that I was using white balance control in wrong way. > > As far as I understand we've got > > V4L2_CID_AUTO_WHITE_BALANCE which activate auto white balance > adjustment in runtime, > V4L2_CID_DO_WHITE_BALANCE_TEMPERATURE specifying absolute kelvin value > > but can't get what V4L2_CID_DO_WHITE_BALANCE is for. My understanding is that V4L2_CID_DO_WHITE_BALANCE enable/disable white balance processing, while with V4L2_CID_DO_WHITE_BALANCE_TEMPERATURE you can specify explicitly ambient temperature. > > I think after issuing V4L2_CID_AUTO_WHITE_BALANCE and > V4L2_CID_WHITE_BALANCE_TEMPERATURE, > the white balance functionality works immediately. Isn't it right? > > What exactly is the button type V4L2_CID_DO_WHITE_BALANCE for? Because > the V4L2 API document says that "(the value is ignored)". Does that > mean that even we have issued V4L2_CID_AUTO_WHITE_BALANCE and > V4L2_CID_WHITE_BALANCE_TEMPERATURE, we can't see the white balance > working at that moment? > > And one more thing. If I want to serve several white balance presets, > like cloudy, dawn, sunny and so on, what should I do? > I think it should be supported as menu type, but most of drivers are > using white balance CID with integer type...then what should I do? > Define preset names with kelvin number like this? I also will like to see controls which specify different kind of white balance mode (cloudy, sunny, tungsten...). in this case we can thing about V4L2_CID_WHITE_BALANCE_TEMPERATURE as 'manual' mode, and let other modes to be handled by some clever algorithms ;). IIvanov > > #define WB_CLOUDY 8000 > > Pretty confusing... anyone knows what should I do? > > Nate > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
