Codec.Picture.Jpg.Internal.Common

Documentation

type DctCoefficients = DcCoefficient

Same as for DcCoefficient, to provide nicer type signatures

data JpgUnpackerParameter

Constructors

JpgUnpackerParameter

Fields

• dcHuffmanTree :: !HuffmanPackedTree
• acHuffmanTree :: !HuffmanPackedTree
• componentIndex :: !Int
• restartInterval :: !Int
• componentWidth :: !Int
• componentHeight :: !Int
• subSampling :: !(Int, Int)
• coefficientRange :: !(Int, Int)
• successiveApprox :: !(Int, Int)
• readerIndex :: !Int
• indiceVector :: !Int

  When in progressive mode, we can have many color in a scan or only one. The indices changes on this fact, when mixed, there is whole MCU for all color components, spanning multiple block lines. With only one color component we use the normal raster order.

• blockIndex :: !Int
• blockMcuX :: !Int
• blockMcuY :: !Int

Instances

Show JpgUnpackerParameter

Defined in Codec.Picture.Jpg.Internal.Common

Methods

showsPrec :: Int -> JpgUnpackerParameter -> ShowS

show :: JpgUnpackerParameter -> String

showList :: [JpgUnpackerParameter] -> ShowS

decodeInt :: Int -> BoolReader s Int32

dcCoefficientDecode :: HuffmanPackedTree -> BoolReader s DcCoefficient

deQuantize :: MacroBlock Int16 -> MutableMacroBlock s Int16 -> ST s (MutableMacroBlock s Int16)

Apply a quantization matrix to a macroblock

decodeRrrrSsss :: HuffmanPackedTree -> BoolReader s (Int, Int)

zigZagReorderForward :: Storable a => MutableMacroBlock s a -> MutableMacroBlock s a -> ST s (MutableMacroBlock s a)

zigZagReorderForwardv :: (Storable a, Num a) => Vector a -> Vector a

zigZagReorder :: MutableMacroBlock s Int16 -> MutableMacroBlock s Int16 -> ST s (MutableMacroBlock s Int16)

inverseDirectCosineTransform :: MutableMacroBlock s Int16 -> ST s (MutableMacroBlock s Int16)

unpackInt :: Int -> BoolReader s Int32

Unpack an int of the given size encoded from MSB to LSB.

unpackMacroBlock

Arguments

:: Int

Component count

-> Int

Width coefficient

-> Int

Height coefficient

-> Int

Component index

-> Int

x

-> Int

y

-> MutableImage s PixelYCbCr8

-> MutableMacroBlock s Int16

-> ST s ()

Given a size coefficient (how much a pixel span horizontally and vertically), the position of the macroblock, return a list of indices and value to be stored in an array (like the final image)

rasterMap :: Monad m => Int -> Int -> (Int -> Int -> m ()) -> m ()

decodeMacroBlock :: MacroBlock DctCoefficients -> MutableMacroBlock s Int16 -> MutableMacroBlock s Int16 -> ST s (MutableMacroBlock s Int16)

This is one of the most important function of the decoding, it form the barebone decoding pipeline for macroblock. It's all there is to know for macro block transformation

decodeRestartInterval :: BoolReader s Int32

toBlockSize :: Int -> Int