Get raster from PNG

This function reads a PNG file and converts it to a raster object with a transparent background for plotting.

Usage

get.raster.from.png(f)

Arguments

f

Filename for PNG image.

Details

When plotting line-drawings as points on a scatterplot (using plot_pics for instance), it can be useful to keep the line drawing background transparent and to be able to control the color in which the image is plotted. Converting PNGs to rasters allows this functionality. This function converts the PNG to a raster object; setting the pc argument in plot_pics then controls the color when plotting the image.