Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Tone Mapping
ID_PV_FILTER_TONEMAPPING
Parameter: Saturation
ID_PV_FILTER_SATURATION
Parameter: Brightness
ID_PV_FILTER_BRIGHTNESS
Parameter: Contrast
ID_PV_FILTER_CONTRAST
Parameter: Exposure
ID_PV_FILTER_EXPOSURE
Parameter: Gamma
ID_PV_FILTER_GAMMA
Parameter: Red
ID_PV_FILTER_RED
Parameter: Green
ID_PV_FILTER_GREEN
Parameter: Blue
ID_PV_FILTER_BLUE
Parameter: Invert
ID_PV_FILTER_INVERT
Parameter: Black Point
ID_PV_FILTER_BLACKPOINT
Parameter: White Point
ID_PV_FILTER_WHITEPOINT
Parameter: Grading Intensity
ID_PV_FILTER_GRAD_INTENSITY
Parameter: Curve Min
ID_PV_FILTER_GRAD_MIN
Parameter: Curve Max
ID_PV_FILTER_GRAD_MAX
Parameter: Curve
ID_PV_FILTER_GRAD_SPLINE_RGB
Parameter: Red
ID_PV_FILTER_GRAD_SPLINE_R
Parameter: Green
ID_PV_FILTER_GRAD_SPLINE_G
Parameter: Blue
ID_PV_FILTER_GRAD_SPLINE_B
Parameter: Reset Values
ID_PV_FILTER_RESET