(This article was first published on theBioBucket*, and kindly contributed to R-bloggers)
...Just read you JPEG and add an alpha channel manually, then assign values for transparency. Of course for printing you need to use a device that accepts alpha.
See how it's done HERE.
To leave a comment for the author, please follow the link and comment on his blog: theBioBucket*.
R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web Scraping) statistics (regression, PCA, time series,ecdf, trading) and more...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
