JuicyPixels-3.2.6.1: Picture loading/serialization (in png, jpeg, bitmap, gif, tga, tiff and radiance)

Safe HaskellNone
LanguageHaskell2010

Codec.Picture.Types

Contents

Description

Module providing the basic types for image manipulation in the library. Defining the types used to store all those _Juicy Pixels_

Synopsis

Types

Image types

data Image a Source

The main type of this package, one that most functions work on, is Image.

Parameterized by the underlying pixel format it forms a rigid type. If you wish to store images of different or unknown pixel formats use DynamicImage.

Image is essentially a rectangular pixel buffer of specified width and height. The coordinates are assumed to start from the upper-left corner of the image, with the horizontal position first and vertical second.

Constructors

Image 

Fields

imageWidth :: !Int

Width of the image in pixels

imageHeight :: !Int

Height of the image in pixels.

imageData :: Vector (PixelBaseComponent a)

Image pixel data. To extract pixels at a given position you should use the helper functions.

Internally pixel data is stored as consecutively packed lines from top to bottom, scanned from left to right within individual lines, from first to last color component within each pixel.

Instances

data MutableImage s a Source

Image or pixel buffer, the coordinates are assumed to start from the upper-left corner of the image, with the horizontal position first, then the vertical one. The image can be transformed in place.

Constructors

MutableImage 

Fields

mutableImageWidth :: !Int

Width of the image in pixels

mutableImageHeight :: !Int

Height of the image in pixels.

mutableImageData :: STVector s (PixelBaseComponent a)

The real image, to extract pixels at some position you should use the helpers functions.

Instances

data DynamicImage Source

Image type enumerating all predefined pixel types. It enables loading and use of images of different pixel types.

Constructors

ImageY8 (Image Pixel8)

A greyscale image.

ImageY16 (Image Pixel16)

A greyscale image with 16bit components

ImageYF (Image PixelF)

A greyscale HDR image

ImageYA8 (Image PixelYA8)

An image in greyscale with an alpha channel.

ImageYA16 (Image PixelYA16)

An image in greyscale with alpha channel on 16 bits.

ImageRGB8 (Image PixelRGB8)

An image in true color.

ImageRGB16 (Image PixelRGB16)

An image in true color with 16bit depth.

ImageRGBF (Image PixelRGBF)

An image with HDR pixels

ImageRGBA8 (Image PixelRGBA8)

An image in true color and an alpha channel.

ImageRGBA16 (Image PixelRGBA16)

A true color image with alpha on 16 bits.

ImageYCbCr8 (Image PixelYCbCr8)

An image in the colorspace used by Jpeg images.

ImageCMYK8 (Image PixelCMYK8)

An image in the colorspace CMYK

ImageCMYK16 (Image PixelCMYK16)

An image in the colorspace CMYK and 16 bits precision

Instances

type Palette = Image PixelRGB8 Source

Type for the palette used in Gif & PNG files.

Image functions

createMutableImage Source

Arguments

:: (Pixel px, PrimMonad m) 
=> Int

Width

-> Int

Height

-> px

Background color

-> m (MutableImage (PrimState m) px) 

Create a mutable image, filled with the given background color.

newMutableImage Source

Arguments

:: (Pixel px, PrimMonad m) 
=> Int

Width

-> Int

Height

-> m (MutableImage (PrimState m) px) 

Create a mutable image with garbage as content. All data is uninitialized.

freezeImage :: (Storable (PixelBaseComponent px), PrimMonad m) => MutableImage (PrimState m) px -> m (Image px) Source

`O(n)` Yield an immutable copy of an image by making a copy of it

unsafeFreezeImage :: (Storable (PixelBaseComponent a), PrimMonad m) => MutableImage (PrimState m) a -> m (Image a) Source

`O(1)` Unsafe convert a mutable image to an immutable one without copying. The mutable image may not be used after this operation.

thawImage :: (Storable (PixelBaseComponent px), PrimMonad m) => Image px -> m (MutableImage (PrimState m) px) Source

`O(n)` Yield a mutable copy of an image by making a copy of it.

unsafeThawImage :: (Storable (PixelBaseComponent px), PrimMonad m) => Image px -> m (MutableImage (PrimState m) px) Source

`O(1)` Unsafe convert an imutable image to an mutable one without copying. The source image shouldn't be used after this operation.

Image Lenses

type Traversal s t a b = forall f. Applicative f => (a -> f b) -> s -> f t Source

Traversal type matching the definition in the Lens package.

imagePixels :: forall pxa pxb. (Pixel pxa, Pixel pxb) => Traversal (Image pxa) (Image pxb) pxa pxb Source

Traversal in "raster" order, from left to right the top to bottom. This traversal is matching pixelMap in spirit.

Since 3.2.4

imageIPixels :: forall pxa pxb. (Pixel pxa, Pixel pxb) => Traversal (Image pxa) (Image pxb) (Int, Int, pxa) pxb Source

Traversal providing the pixel position with it's value. The traversal in raster order, from lef to right, then top to bottom. The traversal match pixelMapXY in spirit.

Since 3.2.4

Pixel types

type Pixel8 = Word8 Source

Type alias for 8bit greyscale pixels. For simplicity, greyscale pixels use plain numbers instead of a separate type.

type Pixel16 = Word16 Source

Type alias for 16bit greyscale pixels.

type Pixel32 = Word32 Source

Type alias for 32bit greyscale pixels.

type PixelF = Float Source

Type alias for 32bit floating point greyscale pixels. The standard bounded value range is mapped to the closed interval [0,1] i.e.

map promotePixel [0, 1 .. 255 :: Pixel8] == [0/255, 1/255 .. 1.0 :: PixelF]

data PixelRGBF Source

HDR pixel type storing floating point 32bit red, green and blue (RGB) information. Same value range and comments apply as for PixelF. Values are stored in the following order:

  • Red
  • Green
  • Blue

Constructors

PixelRGBF !PixelF !PixelF !PixelF 

Type classes

class (Pixel a, Pixel b) => ColorConvertible a b where Source

Implement upcasting for pixel types. Minimal declaration of promotePixel. It is strongly recommended to overload promoteImage to keep performance acceptable

Minimal complete definition

promotePixel

Methods

promotePixel :: a -> b Source

Convert a pixel type to another pixel type. This operation should never lose any data.

promoteImage :: Image a -> Image b Source

Change the underlying pixel type of an image by performing a full copy of it.

class (Storable (PixelBaseComponent a), Num (PixelBaseComponent a), Eq a) => Pixel a where Source

Definition of pixels used in images. Each pixel has a color space, and a representative component (Word8 or Float).

Associated Types

type PixelBaseComponent a :: * Source

Type of the pixel component, "classical" images would have Word8 type as their PixelBaseComponent, HDR image would have Float for instance

Methods

mixWith :: (Int -> PixelBaseComponent a -> PixelBaseComponent a -> PixelBaseComponent a) -> a -> a -> a Source

Call the function for every component of the pixels. For example for RGB pixels mixWith is declared like this:

mixWith f (PixelRGB8 ra ga ba) (PixelRGB8 rb gb bb) =
   PixelRGB8 (f 0 ra rb) (f 1 ga gb) (f 2 ba bb)

mixWithAlpha Source

Arguments

:: (Int -> PixelBaseComponent a -> PixelBaseComponent a -> PixelBaseComponent a)

Function for color component

-> (PixelBaseComponent a -> PixelBaseComponent a -> PixelBaseComponent a)

Function for alpha component

-> a 
-> a 
-> a 

Extension of the mixWith which separate the treatment of the color components of the alpha value (transparency component). For pixel without alpha components, it is equivalent to mixWith.

mixWithAlpha f fa (PixelRGBA8 ra ga ba aa) (PixelRGB8 rb gb bb ab) =
   PixelRGBA8 (f 0 ra rb) (f 1 ga gb) (f 2 ba bb) (fa aa ab)

pixelOpacity :: a -> PixelBaseComponent a Source

Return the opacity of a pixel, if the pixel has an alpha layer, return the alpha value. If the pixel doesn't have an alpha value, return a value representing the opaqueness.

componentCount :: a -> Int Source

Return the number of components of the pixel

colorMap :: (PixelBaseComponent a -> PixelBaseComponent a) -> a -> a Source

Apply a function to each component of a pixel. If the color type possess an alpha (transparency channel), it is treated like the other color components.

pixelBaseIndex :: Image a -> Int -> Int -> Int Source

Calculate the index for the begining of the pixel

mutablePixelBaseIndex :: MutableImage s a -> Int -> Int -> Int Source

Calculate theindex for the begining of the pixel at position x y

pixelAt :: Image a -> Int -> Int -> a Source

Extract a pixel at a given position, (x, y), the origin is assumed to be at the corner top left, positive y to the bottom of the image

readPixel :: PrimMonad m => MutableImage (PrimState m) a -> Int -> Int -> m a Source

Same as pixelAt but for mutable images.

writePixel :: PrimMonad m => MutableImage (PrimState m) a -> Int -> Int -> a -> m () Source

Write a pixel in a mutable image at position x y

unsafePixelAt :: Vector (PixelBaseComponent a) -> Int -> a Source

Unsafe version of pixelAt, read a pixel at the given index without bound checking (if possible). The index is expressed in number (PixelBaseComponent a)

unsafeReadPixel :: PrimMonad m => STVector (PrimState m) (PixelBaseComponent a) -> Int -> m a Source

Unsafe version of readPixel, read a pixel at the given position without bound checking (if possible). The index is expressed in number (PixelBaseComponent a)

unsafeWritePixel :: PrimMonad m => STVector (PrimState m) (PixelBaseComponent a) -> Int -> a -> m () Source

Unsafe version of writePixel, write a pixel at the given position without bound checking. This can be _really_ unsafe. The index is expressed in number (PixelBaseComponent a)

The following graph describe the differents way to convert between pixel types,

  • Nodes describe pixel type
  • Arrows describe functions

class (Pixel a, Pixel b) => ColorSpaceConvertible a b where Source

This class abstract colorspace conversion. This conversion can be lossy, which ColorConvertible cannot

Minimal complete definition

convertPixel

Methods

convertPixel :: a -> b Source

Pass a pixel from a colorspace (say RGB) to the second one (say YCbCr)

convertImage :: Image a -> Image b Source

Helper function to convert a whole image by taking a copy it.

class (Pixel a, Pixel (PixelBaseComponent a)) => LumaPlaneExtractable a where Source

Helper class to help extract a luma plane out of an image or a pixel

Minimal complete definition

computeLuma

Methods

computeLuma :: a -> PixelBaseComponent a Source

Compute the luminance part of a pixel

extractLumaPlane :: Image a -> Image (PixelBaseComponent a) Source

Extract a luma plane out of an image. This method is in the typeclass to help performant implementation.

jpegToGrayScale :: FilePath -> FilePath -> IO ()
jpegToGrayScale source dest

class (Pixel a, Pixel b) => TransparentPixel a b | a -> b where Source

Class modeling transparent pixel, should provide a method to combine transparent pixels

Methods

dropTransparency :: a -> b Source

Just return the opaque pixel value

getTransparency :: a -> PixelBaseComponent a Source

Deprecated: please use pixelOpacity instead

access the transparency (alpha layer) of a given transparent pixel type.

Helper functions

pixelMap :: forall a b. (Pixel a, Pixel b) => (a -> b) -> Image a -> Image b Source

map equivalent for an image, working at the pixel level. Little example : a brightness function for an rgb image

brightnessRGB8 :: Int -> Image PixelRGB8 -> Image PixelRGB8
brightnessRGB8 add = pixelMap brightFunction
     where up v = fromIntegral (fromIntegral v + add)
           brightFunction (PixelRGB8 r g b) =
                   PixelRGB8 (up r) (up g) (up b)

pixelMapXY :: forall a b. (Pixel a, Pixel b) => (Int -> Int -> a -> b) -> Image a -> Image b Source

Just like pixelMap only the function takes the pixel coordinates as additional parameters.

pixelFold :: forall acc pixel. Pixel pixel => (acc -> Int -> Int -> pixel -> acc) -> acc -> Image pixel -> acc Source

Fold over the pixel of an image with a raster scan order: from top to bottom, left to right

pixelFoldM Source

Arguments

:: (Pixel pixel, Monad m) 
=> (acc -> Int -> Int -> pixel -> m acc)

monadic mapping function

-> acc

Initial state

-> Image pixel

Image to fold over

-> m acc 

Fold over the pixel of an image with a raster scan order: from top to bottom, left to right, carrying out a state

pixelFoldMap :: forall m px. (Pixel px, Monoid m) => (px -> m) -> Image px -> m Source

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.

dynamicMap :: (forall pixel. Pixel pixel => Image pixel -> a) -> DynamicImage -> a Source

Helper function to help extract information from dynamic image. To get the width of a dynamic image, you can use the following snippet:

dynWidth :: DynamicImage -> Int
dynWidth img = dynamicMap imageWidth img

dynamicPixelMap :: (forall pixel. Pixel pixel => Image pixel -> Image pixel) -> DynamicImage -> DynamicImage Source

Equivalent of the pixelMap function for the dynamic images. You can perform pixel colorspace independant operations with this function.

For instance, if you want to extract a square crop of any image, without caring about colorspace, you can use the following snippet.

dynSquare :: DynamicImage -> DynamicImage
dynSquare = dynamicPixelMap squareImage

squareImage :: Pixel a => Image a -> Image a
squareImage img = generateImage (\x y -> pixelAt img x y) edge edge
   where edge = min (imageWidth img) (imageHeight img)

dropAlphaLayer :: TransparentPixel a b => Image a -> Image b Source

For any image with an alpha component (transparency), drop it, returning a pure opaque image.

withImage Source

Arguments

:: (Pixel pixel, PrimMonad m) 
=> Int

Image width

-> Int

Image height

-> (Int -> Int -> m pixel)

Generating functions

-> m (Image pixel) 

Create an image using a monadic initializer function. The function will receive values from 0 to width-1 for the x parameter and 0 to height-1 for the y parameter. The coordinates 0,0 are the upper left corner of the image, and (width-1, height-1) the lower right corner.

The function is called for each pixel in the line from left to right (0 to width - 1) and for each line (0 to height - 1).

zipPixelComponent3 :: forall px. Storable (PixelBaseComponent px) => (PixelBaseComponent px -> PixelBaseComponent px -> PixelBaseComponent px -> PixelBaseComponent px) -> Image px -> Image px -> Image px -> Image px Source

Combine, pixel by pixel and component by component the values of 3 different images. Usage example:

averageBrightNess c1 c2 c3 = clamp $ toInt c1 + toInt c2 + toInt c3
  where clamp = fromIntegral . min 0 . max 255
        toInt :: a -> Int
        toInt = fromIntegral
ziPixelComponent3 averageBrightNess img1 img2 img3

generateImage Source

Arguments

:: Pixel a 
=> (Int -> Int -> a)

Generating function, with x and y params.

-> Int

Width in pixels

-> Int

Height in pixels

-> Image a 

Create an image given a function to generate pixels. The function will receive values from 0 to width-1 for the x parameter and 0 to height-1 for the y parameter. The coordinates 0,0 are the upper left corner of the image, and (width-1, height-1) the lower right corner.

for example, to create a small gradient image:

imageCreator :: String -> IO ()
imageCreator path = writePng path $ generateImage pixelRenderer 250 300
   where pixelRenderer x y = PixelRGB8 x y 128

generateFoldImage Source

Arguments

:: Pixel a 
=> (acc -> Int -> Int -> (acc, a))

Function taking the state, x and y

-> acc

Initial state

-> Int

Width in pixels

-> Int

Height in pixels

-> (acc, Image a) 

Create an image given a function to generate pixels. The function will receive values from 0 to width-1 for the x parameter and 0 to height-1 for the y parameter. The coordinates 0,0 are the upper left corner of the image, and (width-1, height-1) the lower right corner.

the acc parameter is a user defined one.

The function is called for each pixel in the line from left to right (0 to width - 1) and for each line (0 to height - 1).

gammaCorrection Source

Arguments

:: PixelF

Gamma value, should be between 0.5 and 3.0

-> Image PixelRGBF

Image to treat.

-> Image PixelRGBF 

Perform a gamma correction for an image with HDR pixels.

toneMapping Source

Arguments

:: PixelF

Exposure parameter

-> Image PixelRGBF

Image to treat.

-> Image PixelRGBF 

Perform a tone mapping operation on an High dynamic range image.

Color plane extraction

data PlaneAlpha Source

Define the plane for the alpha (transparency) component

Constructors

PlaneAlpha 

data PlaneLuma Source

Define the plane for the luma component

Constructors

PlaneLuma 

data PlaneCr Source

Define the plane for the Cr component

Constructors

PlaneCr 

data PlaneCb Source

Define the plane for the Cb component

Constructors

PlaneCb 

data PlaneCyan Source

Define plane for the cyan component of the CMYK color space.

Constructors

PlaneCyan 

data PlaneMagenta Source

Define plane for the magenta component of the CMYK color space.

Constructors

PlaneMagenta 

data PlaneYellow Source

Define plane for the yellow component of the CMYK color space.

Constructors

PlaneYellow 

data PlaneBlack Source

Define plane for the black component of the CMYK color space.

Constructors

PlaneBlack 

extractComponent :: forall px plane. (Pixel px, Pixel (PixelBaseComponent px), PixelBaseComponent (PixelBaseComponent px) ~ PixelBaseComponent px, ColorPlane px plane) => plane -> Image px -> Image (PixelBaseComponent px) Source

Extract a color plane from an image given a present plane in the image examples:

 extractRedPlane :: Image PixelRGB8 -> Image Pixel8
 extractRedPlane = extractComponent PlaneRed

unsafeExtractComponent Source

Arguments

:: (Pixel a, Pixel (PixelBaseComponent a), PixelBaseComponent (PixelBaseComponent a) ~ PixelBaseComponent a) 
=> Int

The component index, beginning at 0 ending at (componentCount - 1)

-> Image a

Source image

-> Image (PixelBaseComponent a) 

Extract a plane of an image. Returns the requested color component as a greyscale image.

If you ask for a component out of bound, the error function will be called.

Packeable writing (unsafe but faster)

class PackeablePixel a where Source

This typeclass exist for performance reason, it allow to pack a pixel value to a simpler "primitive" data type to allow faster writing to moemory.

Associated Types

type PackedRepresentation a Source

Primitive type asociated to the current pixel It's Word32 for PixelRGBA8 for instance

Methods

packPixel :: a -> PackedRepresentation a Source

The packing function, allowing to transform to a primitive.

unpackPixel :: PackedRepresentation a -> a Source

Inverse transformation, to speed up reading

fillImageWith :: (Pixel px, PackeablePixel px, PrimMonad m, Storable (PackedRepresentation px)) => MutableImage (PrimState m) px -> px -> m () Source

This function will fill an image with a simple packeable pixel. It will be faster than any unsafeWritePixel.

readPackedPixelAt Source

Arguments

:: (Pixel px, PackeablePixel px, Storable (PackedRepresentation px), PrimMonad m) 
=> MutableImage (PrimState m) px

Image to read from

-> Int

Index in (PixelBaseComponent px) count

-> m px 

Read a packeable pixel from an image. Equivalent to unsafeReadPixel

writePackedPixelAt Source

Arguments

:: (Pixel px, PackeablePixel px, Storable (PackedRepresentation px), PrimMonad m) 
=> MutableImage (PrimState m) px

Image to write into

-> Int

Index in (PixelBaseComponent px) count

-> px

Pixel to write

-> m () 

Write a packeable pixel into an image. equivalent to unsafeWritePixel.

unsafeWritePixelBetweenAt Source

Arguments

:: (PrimMonad m, Pixel px, PackeablePixel px, Storable (PackedRepresentation px)) 
=> MutableImage (PrimState m) px

Image to write into

-> px

Pixel to write

-> Int

Start index in pixel base component

-> Int

pixel count of pixel to write

-> m () 

Fill a packeable pixel between two bounds.