isophote
/ˈʌɪsə(ʊ)fəʊt
/noun
A line in a diagram connecting points where the intensity of light is the same.The result keeps the sharpness of bicubic interpolation while smoothing the isophotes to reduce jagged pixelization artifacts.
Origin
Early 20th century: from iso- 'equal' + Greek phōs, phōt- 'light'.