img2pdf.hs

import Codec.Picture
import Codec.Picture.Types
import Graphics.PDF
import Codec.Picture.Saving
import Data.ByteString.Lazy as B
import System.IO (hClose)
import System.IO.Temp
import System.Environment

main :: IO ()
main = do
  [inp,outp] <- getArgs
  Right image <- readImage inp
  let w = dynamicMap imageWidth image
      h = dynamicMap imageHeight image
      rect = PDFRect 0 0 w h
  withSystemTempFile "img2pdf.jpg" $ \p hndl -> do
    B.hPut hndl $ imageToJpg 100 image
    hClose hndl
    Right jpgf <- readJpegFile p
    runPdf outp standardDocInfo rect $ do
      page <- addPage Nothing
      img <- createPDFJpeg jpgf
      drawWithPage page $ withNewContext $ drawXObject img