View ARGBType Img as an UnsignedByteType Img



Before I write one: is there any View or Converter to use an img of ARGBType as a luminance image ( each pixel as (r + g + b) / 3 ), that is, an 8-bit grayscale image, using UnsignedByteType? It’s a common enough operation in image processing that I would like to have a built-in one-command way to do it.

I’d imagine that if ARGBType was to be made a RealType, it would be basically the same. Rather than muck with the Type hierarchy, a Converter would do just fine.