Codec.Picture.Metadata

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

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

Show Metadatas

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Metadatas -> ShowS

show :: Metadatas -> String

showList :: [Metadatas] -> ShowS

Semigroup Metadatas

Defined in Codec.Picture.Metadata

Methods

(<>) :: Metadatas -> Metadatas -> Metadatas

sconcat :: NonEmpty Metadatas -> Metadatas

stimes :: Integral b => b -> Metadatas -> Metadatas

Monoid Metadatas

Defined in Codec.Picture.Metadata

Methods

mempty :: Metadatas

mappend :: Metadatas -> Metadatas -> Metadatas

mconcat :: [Metadatas] -> Metadatas

NFData Metadatas

Defined in Codec.Picture.Metadata

Methods

rnf :: Metadatas -> ()

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.

Constructors

Gamma :: Keys Double

ColorSpace :: Keys ColorSpace

Format :: Keys SourceFormat

DpiX :: Keys Word

DpiY :: Keys Word

Width :: Keys Word

Height :: Keys Word

Title :: Keys String

Description :: Keys String

Author :: Keys String

Copyright :: Keys String

Software :: Keys String

Comment :: Keys String

Disclaimer :: Keys String

Source :: Keys String

Warning :: Keys String

Exif :: !ExifTag -> Keys ExifData

Unknown :: !String -> Keys Value

Instances

Eq (Keys a)

Defined in Codec.Picture.Metadata

Methods

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

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

Show (Elem Keys)

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Elem Keys -> ShowS

show :: Elem Keys -> String

showList :: [Elem Keys] -> ShowS

Show (Keys a)

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Keys a -> ShowS

show :: Keys a -> String

showList :: [Keys a] -> ShowS

NFData (Elem Keys)

Defined in Codec.Picture.Metadata

Methods

rnf :: Elem Keys -> ()

data Value

Encode values for unknown information

Constructors

Int !Int

Double !Double

String !String

Instances

Eq Value

Defined in Codec.Picture.Metadata

Methods

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

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

Show Value

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Value -> ShowS

show :: Value -> String

showList :: [Value] -> ShowS

NFData Value

Defined in Codec.Picture.Metadata

Methods

rnf :: Value -> ()

data Elem k

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

Constructors

(Show a, NFData a) => !(k a) :=> a

Instances

Show (Elem Keys)

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> Elem Keys -> ShowS

show :: Elem Keys -> String

showList :: [Elem Keys] -> ShowS

NFData (Elem Keys)

Defined in Codec.Picture.Metadata

Methods

rnf :: Elem Keys -> ()

data SourceFormat

Type describing the original file format of the file.

Constructors

SourceJpeg

SourceGif

SourceBitmap

SourceTiff

SourcePng

SourceHDR

SourceTGA

Instances

Eq SourceFormat

Defined in Codec.Picture.Metadata

Methods

(==) :: SourceFormat -> SourceFormat -> Bool

(/=) :: SourceFormat -> SourceFormat -> Bool

Show SourceFormat

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> SourceFormat -> ShowS

show :: SourceFormat -> String

showList :: [SourceFormat] -> ShowS

NFData SourceFormat

Defined in Codec.Picture.Metadata

Methods

rnf :: SourceFormat -> ()

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.

Constructors

SRGB

WindowsBitmapColorSpace !ByteString

ICCProfile !ByteString

Instances

Eq ColorSpace

Defined in Codec.Picture.Metadata

Methods

(==) :: ColorSpace -> ColorSpace -> Bool

(/=) :: ColorSpace -> ColorSpace -> Bool

Show ColorSpace

Defined in Codec.Picture.Metadata

Methods

showsPrec :: Int -> ColorSpace -> ShowS

show :: ColorSpace -> String

showList :: [ColorSpace] -> ShowS

NFData ColorSpace

Defined in Codec.Picture.Metadata

Methods

rnf :: ColorSpace -> ()

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