Safe Haskell | None |
---|---|
Language | Haskell2010 |
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
- data Metadatas
- data Keys a where
- Gamma :: Keys Double
- DpiX :: Keys Word
- DpiY :: 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
- data Value
- data Elem k = forall a . (Show a, NFData a) => !(k a) :=> a
- lookup :: Keys a -> Metadatas -> Maybe a
- empty :: Metadatas
- insert :: (Show a, NFData a) => Keys a -> a -> Metadatas -> Metadatas
- delete :: Keys a -> Metadatas -> Metadatas
- singleton :: (Show a, NFData a) => Keys a -> a -> Metadatas
- foldl' :: (acc -> Elem Keys -> acc) -> acc -> Metadatas -> acc
- foldMap :: Monoid m => (Elem Keys -> m) -> Metadatas -> m
- mkDpiMetadata :: Word -> Metadatas
- dotsPerMeterToDotPerInch :: Word -> Word
- dotPerInchToDotsPerMeter :: Word -> Word
- dotsPerCentiMeterToDotPerInch :: Word -> Word
Types
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.
Store various additional information about an image. If something is not recognized, it can be stored in an unknown tag.
Gamma :: Keys Double | |
DpiX :: Keys Word | |
DpiY :: 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 |
Encode values for unknown information
Element describing a metadata and it's (typed) associated value.
Functions
insert :: (Show a, NFData a) => Keys a -> a -> Metadatas -> Metadatas Source
Insert an element in the metadatas, if an element with the same key is present, it is overwritten.
delete :: Keys a -> Metadatas -> Metadatas Source
Remove an element of the given keys from the metadatas. If not present does nothing.
singleton :: (Show a, NFData a) => Keys a -> a -> Metadatas Source
Create metadatas with a single element.
Folding
foldl' :: (acc -> Elem Keys -> acc) -> acc -> Metadatas -> acc Source
Strict left fold of the metadatas
Helper functions
mkDpiMetadata :: Word -> Metadatas Source
Create metadatas indicating the resolution, with DpiX == DpiY
Conversion functions
dotsPerMeterToDotPerInch :: Word -> Word Source
Conversion from dpm to dpi
dotPerInchToDotsPerMeter :: Word -> Word Source
Conversion from dpi to dpm
dotsPerCentiMeterToDotPerInch :: Word -> Word Source
Conversion dpcm -> dpi