package image //func getBighnessMap(map [][]Pixel) [][]float64{} func (pix Pixel) Brightness() float64 { R := float64(pix.R) G := float64(pix.G) B := float64(pix.B) A := float64(pix.A) brightness := (0.2126*R + 0.7152*G + 0.0722*B) /255 return brightness * (A / 255) }