hdrGainMapImage
An optional key and value to save a gain map channel to a JPEG or HEIF.
Declaration
static let hdrGainMapImage: CIImageRepresentationOptionDiscussion
The value for this key needs to be a monochrome CIImage instance.
If the hdrGainMapAsRGB option it true, then it needs to be an RGB CIImage instance.
The /CIImage/properties should contain metadata information equivalent to what is returned when initializing an image using auxiliaryHDRGainMap.