PhilipsHue + v4l2 grabber + low light scenes - Red/Blue light output

Hi,
I'm running Hyperion on a Raspberry Pi 3 B+ running raspbian-stretch with 4 philips hue bulbs in my living room (one in each corner of the room). I don't have any LED's around the screen at the moment, and have been trying to configure Hyperion to produce a nice subtle ambient affect, without flickering and sporadic changes in colour.

I'm fairly happy with my config, and have had to introduce smoothing (suggested workaround) for the open issue HERE.

The only issue i continue to have is during low light scenes, where the lights are getting close to turning off - the lights get sent either a bright blue or red colour (colour depends on the nature of the video input). I spent a while testing my setup with Game of Thrones last night, re-playing certain tricky scenes to fine tune my config. Whenever there is a low light scene with candlelight, or yellow light/skin tone the hue bulbs will glow red. I managed to capture a screenshot from the USB videograbber and the video signal is perfect, has no visual red present and i would expect the lights to turn more yellow than red here:

Alternatively, any of the GOT scenes that have snow in tend to turn to blue before turning off.

Is this a known issue, or is there a workaround?

I spent a while experimenting with both the grabber-v4l2.red/green/bluethreshold, along with the blackborderdetector.threshold values. I've also followed the blackborderdetector.threshold tutorial by using a colour picker on the screengrab to get the correct value, which gave me ~8% and still did not fully correct the issue.

Cheers

EDIT:

Zitat

OK, i didn't realise when HyperCon does its video grab: it uses different frameDecimation/sizeDecimation values than the default 2/8. Therefore when i have the strange red/blue lighting, and i've been grabbing the USB grabber through HyperCon - that Hyperion will actually be seeing a different resultant image, i'm assuming the image will be considerably reduced down and colours averaged out - which might explain what i'm seeing. Hyperion uses barely any CPU on my Pi ~1%, are there any better values to use here instead?
How can i manually obtain the same image that Hyperion will see with my current vl42 settings? ssh command?

[MEDIA=pastebin]T4KVRWgm[/MEDIA]

Just a quick update, this issue does not exist on the latest compiled version of Hyperion.ng. Apart from the outstanding issue of switchOffOnBlack=true not working, the colours and functionality .ng provides is a vast improvement over the current version of Hyperion.
I gather than the issue i was seeing could be fixed with calibration, however with .ng i do not need to calibrate the colours of the bulbs as they work perfectly.

Just for confirmation now that this is resolved, I'm using the same hardware and configuration values for my v4l2 configuration, therefore the sizeDecimation value of 8 is perfectly fine, as since the code internally doesnt look to be blurring on downsample, just removing some of the pixels - everything seems to work just as well with a value of 8 OR 2, and therefore the overall colours from the grabber are unadjusted.