iOS camera preview color temperature

Question

Is it somehow possible to get the white balance color temperature (and tint) from a camera preview or from a saved picture?

I am able to get other exposure values in real time based on this SO thread, like f-stop, exposure time, ISO, etc. The white balance always returns just 0, probably meaning "auto white balance". When I save an image from live preview the EXIF data has the white balance still just a zero.

I need to get the white balance color temperature in Kelvins the image/live camera preview was balanced to. I read some stuff about hidden APIs to get/set color temperature, but I cannot use hidden APIs. Any ideas if/how is this possible on iOS 7? Thank you.

Answer 1

No, I'm afraid it's not possible (at least not without the hidden APIs to which you refer—and they don't use degK, but some internal system). And yes, 0 is the code for Auto white balance (1 would be manual).

Answer 2

It seems like it's possible to get values with the current API, you can check this out if you're still interested. https://developer.apple.com/documentation/avfoundation/avcapturedevice/whitebalancetemperatureandtintvalues