If field is white

[Anto_bt]

I need formula in Formcalc IF field backround color is white than in my field to write "YES"

[Anto_bt]

if(xfa.resolveNode("Page1.#subform.Januar.Table1.Row1[20].JDN21").fillColor == "255,255,255") then

$ = "YES" else

$ = "No"

endif

This is function