foldMap package:JuicyPixels

foldMap :: Monoid m => (Elem Keys -> m) -> Metadatas -> m
JuicyPixels Codec.Picture.Metadata
foldMap equivalent for metadatas.
pixelFoldMap :: forall m px . (Pixel px, Monoid m) => (px -> m) -> Image px -> m
JuicyPixels Codec.Picture.Types
Fold over the pixel of an image with a raster scan order: from top to bottom, left to right. This functions is analog to the foldMap from the Foldable typeclass, but due to the Pixel constraint, Image cannot be made an instance of it.