Hey I would like to ensure we don't lose focus < See what I did there
on the main issue of this thread, which is being able to turn off AWB preferably by setting a fixed Kelvin value. Someone else suggested being able to take a reference shot of a gray card and storing and that would be great but a good much less complex start would be to just allow a K value to be passed in as a pram when you take the shot.
Thanks for you efforts I know for everyone who enjoys the fruit (Raspberry flavored) of your labors there is something that is most important. My request is just another one of these. In my case I do have a potential of getting my company to buy thousands of Pi s for this application I am working on but it is dead in the water if I can not accurately set a white balance. Again I am going to the extra effort of having a completely controlled environment where the light temp is a constant. Getting the correct color is critical.
Working from a Kelvin value means that someone has to have then calibrated the red/blue gain required for this particular sensor for each of those temperature values - not a trivial task.
Thinking the issue through, the first job is to work out why AWB is rerunning the calcs on a capture even when the AWB mode is off. That sounds like a bug to me, but I'm not responsible for that algorithm and there may be a more fundamental reason.
Second job would be to add a new AWB mode that allows user provided red and blue gains to be specified. Not quite as tidy as setting a Kelvin value, but gets the same result without needing lots of calibration. (IIRC the red and blue gains are stored as text in the Makernote field of any JPEG capture, so you can therefore get the relevant numbers quite easily.)
It depends on how cooperative the AWB algorithm is, but it feels like it shouldn't be too major a job. I'll see what time I have available to look into it.
<grumpy man mode>I'm not knocking your project, but generally promising sales doesn't have that much influence (at least to me). Whilst we all support Raspberry Pi, a lot of us are Broadcom employees and therefore sales figures have little direct bearing on us. We're doing this as volunteers who happen to have access to the source code and think it's fun.
If a feature is absolutely essential to you, then it is the Foundation that you need to convince. They do have the option of contracting Broadcom or select others to do the work, but that has a financial implication to them.</grumpy man mode>
As a slightly less grumpy man at the moment, give me a chance to have a play and I'll see what can be done.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.