Codec.Picture.Repa

Primitive types and operations

data Img a

Img a is an image where the phantom type a indicates the image format

All images are held in a three dimensional repa array. If the image format is only two dimensional (ex: R, G, or B) then the shape is Z :. y :. x :. 1.

imgData :: Img a -> Array U DIM3 Word8

convertImage :: ConvertImage a b => a -> Img b

Converts from JuicyPixels type (Usually Image or DynamicImage to the repa-based Img type.

Generic interface

readImage :: DecodeImage a => FilePath -> IO (Either String (Img a))

decodeImage :: DecodeImage a => ByteString -> Either String (Img a)

Monomorphic image decoding functions

readImageRGBA :: FilePath -> IO (Either String (Img RGBA))

readImageRGB :: FilePath -> IO (Either String (Img RGB))

readImageR :: FilePath -> IO (Either String (Img R))

readImageG :: FilePath -> IO (Either String (Img G))

readImageB :: FilePath -> IO (Either String (Img B))

decodeImageRGBA :: ByteString -> Either String (Img RGBA)

decodeImageRGB :: ByteString -> Either String (Img RGB)

decodeImageR :: ByteString -> Either String (Img R)

decodeImageG :: ByteString -> Either String (Img G)

decodeImageB :: ByteString -> Either String (Img B)

Image Representations (Phantom Types)

data RGBA

A 32-bit image with full red, green, blue and alpha channels.

The image is stored as Height x Width x ColorChannel.

The color channel is stored in RGBA order. For the common OpenGL ordering users might want to use reverseColorChannel.

Instances

DecodeImage RGBA

ConvertImage DynamicImage RGBA

(ToRGBAChannels a, Pixel a) => ConvertImage (Image a) RGBA

data RGB

A 24-bit image with red, green and blue channels

Instances

DecodeImage RGB

ConvertImage DynamicImage RGB

(ToRGBAChannels a, Pixel a) => ConvertImage (Image a) RGB

data R

An all-red image

Instances

DecodeImage R

ConvertImage DynamicImage R

(ToRGBAChannels a, Pixel a) => ConvertImage (Image a) R

data G

An all-green image

Instances

DecodeImage G

ConvertImage DynamicImage G

(ToRGBAChannels a, Pixel a) => ConvertImage (Image a) G

data B

An all-blue image

Instances

DecodeImage B

ConvertImage DynamicImage B

(ToRGBAChannels a, Pixel a) => ConvertImage (Image a) B

Helper Functions (useful for OpenGL etc.)

toVector :: Img a -> Vector Word8

Convert an Img to a storable Vector, often useful for OpenGL and other C interfaces. Notice the format of the data depends on the type of the 'Img a'. O(n)

toForeignPtr :: Img RGBA -> (ForeignPtr Word8, Int, Int)

O(n) returning (pointer, length, offset)

reverseColorChannel :: Img a -> Img a

By default, the color channel for RGBA indexes 0 -> R, 1 -> G, 2 -> B, 3 -> A. This is the AGBR byte ordering in OpenGL. For rendering with OpenGL's RGBA PixelFormat be sure to call reverseColorChannel before converting to a Vector (or directly to bytestring via 'repa-bytestring').

flipHorizontally :: Img a -> Img b

flipVertically :: Img a -> Img a

Internal Functionallity (exported for advanced uses)

class ToRGBAChannels a where

Methods

toRGBAChannels :: a -> PixelRGBA8

Instances

ToRGBAChannels Pixel8

ToRGBAChannels PixelYA8

ToRGBAChannels PixelRGB8

ToRGBAChannels PixelYCbCr8

ToRGBAChannels PixelRGBA8