Extend cudaimgproc::demosaicing for f32

[apbr]

Extend cudaimgproc::demosaicing to also allow images with f32 values.

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[llschloesser]

@apbr please see #3777

It seems like adding 32f to that PR would be easier than deconflicting with this one and we might get all functionality merged sooner. Can I ask what sensor you are using where you have 32f raw pixels?

[apbr]

@llschloesser #3777 was merged 1 hour after your comment. So I'll just rebase my PR.

Can I ask what sensor you are using where you have 32f raw pixels?

We do some image processing steps before the debayering. Their resulting datatype is f32. So it's not directly from the sensor.

[llschloesser]

If you follow the template pattern of the earlier PR you'll get 32f to gray and 4 channel, there is no need to restrict to 3 channel.

[apbr]

If you follow the template pattern of the earlier PR you'll get 32f to gray and 4 channel, there is no need to restrict to 3 channel.

Good point, I'll rework and test it.