### Name: convertColor ### Title: Convert between colour spaces ### Aliases: convertColor colorspaces ### Keywords: color ### ** Examples require(graphics); require(stats) # for na.omit par(mfrow=c(2,2)) ## The displayable colors from four planes of Lab space ab <- expand.grid(a=(-10:15)*10,b=(-15:10)*10) Lab <- cbind(L=20,ab) srgb <- convertColor(Lab,from="Lab",to="sRGB",clip=NA) clipped <- attr(na.omit(srgb),"na.action") srgb[clipped,] <- 0 cols <- rgb(srgb[,1],srgb[,2],srgb[,3]) image((-10:15)*10,(-15:10)*10,matrix(1:(26*26),ncol=26),col=cols, xlab="a",ylab="b",main="Lab: L=20") Lab <- cbind(L=40,ab) srgb <- convertColor(Lab,from="Lab",to="sRGB",clip=NA) clipped <- attr(na.omit(srgb),"na.action") srgb[clipped,] <- 0 cols <- rgb(srgb[,1],srgb[,2],srgb[,3]) image((-10:15)*10,(-15:10)*10,matrix(1:(26*26),ncol=26),col=cols, xlab="a",ylab="b",main="Lab: L=40") Lab <- cbind(L=60,ab) srgb <- convertColor(Lab,from="Lab",to="sRGB",clip=NA) clipped <- attr(na.omit(srgb),"na.action") srgb[clipped,] <- 0 cols <- rgb(srgb[,1],srgb[,2],srgb[,3]) image((-10:15)*10,(-15:10)*10,matrix(1:(26*26),ncol=26),col=cols, xlab="a",ylab="b",main="Lab: L=60") Lab <- cbind(L=80,ab) srgb <- convertColor(Lab,from="Lab",to="sRGB",clip=NA) clipped <- attr(na.omit(srgb),"na.action") srgb[clipped,] <- 0 cols <- rgb(srgb[,1],srgb[,2],srgb[,3]) image((-10:15)*10,(-15:10)*10,matrix(1:(26*26),ncol=26),col=cols, xlab="a",ylab="b",main="Lab: L=80") (cols <- t(col2rgb(palette()))) (lab <- convertColor(cols,from="sRGB",to="Lab",scale.in=255)) round(convertColor(lab,from="Lab",to="sRGB",scale.out=255))