R: add title to wordcloud graphics / png

Question

I have some working R code that generates a tag cloud from a term-document matrix.

Now I want to create a whole bunch of tag clouds from many documents, and to inspect

Answer 1

One idea is to import the images , and save again them using grid.raster, and add the titile using grid.text. For example:

ll <- list.files(patt='*.png')
library(png)
library(grid)
imgs <- lapply(ll,function(x){
  img <- as.raster(readPNG(x))
  ## get the file name
  x.name <- gsub('(.*).png','\\1',x)
  ## new device for new image version
  png(file =paste(x.name,'_modified','.png',sep=''))
  grid.raster(img)
  ## here I add title
  grid.text(label = x.name,x=0.5,y=0.9,gp=gpar(cex=2))
  dev.off()

})