I am able to add a jpeg onto a base graphics plot using: ref:Adding a picture to plot in R
require(jpeg)
img <- readJPEG("myfile.jpeg")
#now open a plot window with coordinates
par(oma=c(2, 0, 3, 0))
plot(1:10, ty="n")
mtext("I would like to put logo here", adj=0, cex=1.5, line=1, side=3, outer=TRUE)
#specify the position of the image through bottom-left and top-right coords
rasterImage(img, 2, 2, 4, 4)
But how can I add a jpeg into the top lhs outer margin? I have a logo and I would like to put it there.