On Fri, 8 Mar 2013, Benoît Thébaudeau wrote: > Hi Javier, > > On Friday, March 8, 2013 1:37:38 PM, Javier Martin wrote: > > Hi Benoît, > > > > On 8 March 2013 12:53, Benoît Thébaudeau <benoit.thebaudeau@xxxxxxxxxxxx> > > wrote: > > > > > >> Regarding 3, you say it works nicely for you in kernel 3.4.5. I've > > >> migrated my code to that version but I still get colours that lack > > >> enough intensity. > > >> This is a snapshot "a" taken with my mobile which is much more similar > > >> to what I can really see with my eyes: > > >> http://img96.imageshack.us/img96/1451/20130307171334.jpg > > >> > > >> This is a similar snapshot "b" taken with mt9m131 in my board. It > > >> shows that colours tend to be dull and darker, specially green: > > >> http://img703.imageshack.us/img703/6025/testgo.jpg > > >> > > >> Are the snapshots you take with your HW more similar to "a" or to > > >> "b"? Perhaps I am being too picky with the image quality and this is > > >> all what mt9m131 can do? > > > > > > I fear that my captures are closer to "b". Your description of "3" was > > > giving > > > the impression of flashy colors. But the impression that this sensor gives > > > me is > > > rather a superimposed gray film. This effect is more or less visible > > > depending > > > on the lighting conditions, but it never seems to produce high quality > > > colors. > > > > Yes, yours is probably is the best description for the image quality > > this sensor provides with the current settings. > > Well, this is a bit disappointing. Let's see if some other user has a > > similar experience with it or comes up with a way to improve it. > > > > I've tested several things such as disabling auto white balance and > > auto exposure and try to manually change colour gains but it seems the > > sensor simply ignores the latter. > > > > There is an evaluation board from Aptina > > (http://www.digikey.com/product-detail/es/MT9M131C12STCH%20ES/557-1251-ND/1643271) > > but, unfortunately, I don't have one of these available. It could be > > very useful to test the sensor with this board with the configuration > > Aptina recommends and see whether the "grey layer effect" still > > persists. > > It is perhaps also possible to find their recommended register settings > somewhere without having this evaluation board. I just tested my mt9m131 camera on a i.MX31 board, if not this your email I don't think I'd be alarmed by the image quality it's producing, maybe I'm just less picky:-) And yes, in general I agree, I think, this level of image quality tuning is difficult to achieve on modern cameras with 100s of fine-tuning knobs. I'll try to re-test this camera in day light conditions and post my best shot :) Thanks Guennadi > > I will try to contact Aptina's technical support but, according to my > > previous experience, there is no guarantee we get a clarifying answer. > > I'll keep you updated nevertheless. > > Thanks. > > Best regards, > Benoît > --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- 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
