JuicyPixels-3.3.9: Picture loading/serialization (in png, jpeg, bitmap, gif, tga, tiff and radiance)
Safe HaskellNone
LanguageHaskell2010

Codec.Picture.Metadata

Description

This module expose a common "metadata" storage for various image type. Different format can generate different metadatas, and write only a part of them.

Since version 3.2.5

Synopsis

Types

data Metadatas #

Dependent storage used for metadatas. All metadatas of a given kind are unique within this container.

The current data structure is based on list, so bad performances can be expected.

Instances

Instances details
NFData Metadatas # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: Metadatas -> () #

Monoid Metadatas # 
Instance details

Defined in Codec.Picture.Metadata

Semigroup Metadatas # 
Instance details

Defined in Codec.Picture.Metadata

Show Metadatas # 
Instance details

Defined in Codec.Picture.Metadata

data Keys a where #

Store various additional information about an image. If something is not recognized, it can be stored in an unknown tag.

  • DpiX Dot per inch on this x axis.
  • DpiY Dot per inch on this y axis.
  • Width Image width in pixel. Relying on the metadata for this information can avoid the full decompression of the image. Ignored for image writing.
  • Height Image height in pixels. Relying on the metadata for this information can void the full decompression of the image. Ignored for image writing.
  • ColorProfile An unparsed ICC color profile. Currently only supported by the Bitmap format.
  • Unknown unlikely to be decoded, but usefull for metadata writing
  • Exif Exif tag and associated data.

Instances

Instances details
NFData (Elem Keys) # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: Elem Keys -> () #

Show (Elem Keys) # 
Instance details

Defined in Codec.Picture.Metadata

Show (Keys a) # 
Instance details

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Keys a -> ShowS #

show :: Keys a -> String #

showList :: [Keys a] -> ShowS #

Eq (Keys a) # 
Instance details

Defined in Codec.Picture.Metadata

Methods

(==) :: Keys a -> Keys a -> Bool #

(/=) :: Keys a -> Keys a -> Bool #

data Value #

Encode values for unknown information

Constructors

Int !Int 
Double !Double 
String !String 

Instances

Instances details
NFData Value # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: Value -> () #

Show Value # 
Instance details

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Value -> ShowS #

show :: Value -> String #

showList :: [Value] -> ShowS #

Eq Value # 
Instance details

Defined in Codec.Picture.Metadata

Methods

(==) :: Value -> Value -> Bool #

(/=) :: Value -> Value -> Bool #

data Elem (k :: Type -> Type) #

Element describing a metadata and it's (typed) associated value.

Constructors

(Show a, NFData a) => !(k a) :=> a 

Instances

Instances details
NFData (Elem Keys) # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: Elem Keys -> () #

Show (Elem Keys) # 
Instance details

Defined in Codec.Picture.Metadata

data SourceFormat #

Type describing the original file format of the file.

Instances

Instances details
NFData SourceFormat # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: SourceFormat -> () #

Show SourceFormat # 
Instance details

Defined in Codec.Picture.Metadata

Eq SourceFormat # 
Instance details

Defined in Codec.Picture.Metadata

data ColorSpace #

The same color values may result in slightly different colors on different devices. To get consistent colors accross multiple devices we need a way of mapping color values from a source device into their equivalents on the target device.

The solution is essentially to define, for each device, a family of mappings that convert between device colors and standard CIEXYZ or CIELAB colors. The collection of mappings for a device is known as the 'color-profile' of that device, and each color-profile can be thought of as describing a 'color-space'.

If we know the color-space of the input pixels, and the color space of the output device, then we can convert the colors in the image to their equivalents on the output device.

JuicyPixels does not parse color-profiles or attempt to perform color correction.

The following color space types are recognised:

  • sRGB: Standard RGB color space.
  • Windows BMP color space: Color space information embedded within a V4 Windows BMP file.
  • ICC profile: An ICC color profile.

Instances

Instances details
NFData ColorSpace # 
Instance details

Defined in Codec.Picture.Metadata

Methods

rnf :: ColorSpace -> () #

Show ColorSpace # 
Instance details

Defined in Codec.Picture.Metadata

Eq ColorSpace # 
Instance details

Defined in Codec.Picture.Metadata

Functions

lookup :: Keys a -> Metadatas -> Maybe a #

Search a metadata with the given key.

empty :: Metadatas #

Empty metadatas. Favor mempty

insert :: (Show a, NFData a) => Keys a -> a -> Metadatas -> Metadatas #

Insert an element in the metadatas, if an element with the same key is present, it is overwritten.

delete :: Keys a -> Metadatas -> Metadatas #

Remove an element of the given keys from the metadatas. If not present does nothing.

singleton :: (Show a, NFData a) => Keys a -> a -> Metadatas #

Create metadatas with a single element.

Folding

foldl' :: (acc -> Elem Keys -> acc) -> acc -> Metadatas -> acc #

Strict left fold of the metadatas

foldMap :: Monoid m => (Elem Keys -> m) -> Metadatas -> m #

foldMap equivalent for metadatas.

Helper functions

mkDpiMetadata :: Word -> Metadatas #

Create metadatas indicating the resolution, with DpiX == DpiY

mkSizeMetadata :: Integral n => n -> n -> Metadatas #

Create metadatas holding width and height information.

basicMetadata :: Integral nSize => SourceFormat -> nSize -> nSize -> Metadatas #

Create simple metadatas with Format, Width & Height

simpleMetadata :: (Integral nSize, Integral nDpi) => SourceFormat -> nSize -> nSize -> nDpi -> nDpi -> Metadatas #

Create simple metadatas with Format, Width, Height, DpiX & DpiY

extractExifMetas :: Metadatas -> [(ExifTag, ExifData)] #

Extract all Exif specific metadatas

Conversion functions

dotsPerMeterToDotPerInch :: Word -> Word #

Conversion from dpm to dpi

dotPerInchToDotsPerMeter :: Word -> Word #

Conversion from dpi to dpm

dotsPerCentiMeterToDotPerInch :: Word -> Word #

Conversion dpcm -> dpi