Which haskell library will let me save a 2D array/vector to a png/jpg/gif… file?

Question

I am playing around with haskell, starting with simple plotting programs to wet my feet. I need a library that will let me save a 2D array/vector to an image file. I don\'t

Answer 1

A new combination is:

• repa; for n-dimensional arrays, plus
• repa-devil, for image loading in dozens of formats.

Repa is the only widely used array library that is automatically parallelized.

An example, from the repa tutorial, using readImage and writeImage, to read an image, rotate it, and write it back out, in whatever format:

import System.Environment
import Data.Word
import Data.Array.Repa hiding ((++))
import Data.Array.Repa.IO.DevIL

main = do
    [f] <- getArgs
    runIL $ do
        v   <- readImage f
        writeImage ("flip-"++f) (rot180 v)

rot180 :: Array DIM3 Word8 -> Array DIM3 Word8
rot180 g = backpermute e flop g
    where
        e@(Z :. x :. y :. _)   = extent g

        flop (Z :. i         :. j         :. k) =
             (Z :. x - i - 1 :. y - j - 1 :. k)