Tiny jpeg cleanups/refactoring

Twinside · Sep 4, 2016 · b2ddfd8 · b2ddfd8
1 parent c5d23dd
commit b2ddfd8
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Showing 4 changed files with 39 additions and 28 deletions.
diff --git a/saferizer.ps1 b/saferizer.ps1
@@ -1,11 +1,13 @@
-ls -r | match "\.hs$" | % {
-    sed -i -e 's:\.unsafeWrite:.write:g' $_.fullname
-    sed -i -e 's:\.unsafeRead:.read:g' $_.fullname
-    sed -i -e 's:`V.unsafeIndex`:V.!:g' $_.fullname
-    sed -i -e 's:`VS\.unsafeIndex`:VS.!:g' $_.fullname
-    sed -i -e 's:BU.unsafeIndex:B.index:g' $_.fullname
-    sed -i -e 's:V.unsafeIndex:(V.!):g' $_.fullname
-    sed -i -e 's:VS.unsafeIndex:(VS.!):g' $_.fullname
-    sed -i -e 's:unsafeIndex:!:g' $_.fullname
-    sed -i -e 's:unsafeFreeze:freeze:g' $_.fullname
+$sed = "C:\MinGW\msys\1.0\bin\sed.exe"
+
+ls -r src | match "\.hs$" | % {
+    & $sed -i -e 's:\.unsafeWrite:.write:g' $_.fullname;
+    & $sed -i -e 's:\.unsafeRead:.read:g' $_.fullname;
+    & $sed -i -e 's:`V.unsafeIndex`:V.!:g' $_.fullname;
+    & $sed -i -e 's:`VS\.unsafeIndex`:VS.!:g' $_.fullname;
+    & $sed -i -e 's:BU.unsafeIndex:B.index:g' $_.fullname;
+    & $sed -i -e 's:V.unsafeIndex:(V.!):g' $_.fullname;
+    & $sed -i -e 's:VS.unsafeIndex:(VS.!):g' $_.fullname;
+    & $sed -i -e 's:unsafeIndex:!:g' $_.fullname;
+    & $sed -i -e 's:unsafeFreeze:freeze:g' $_.fullname;
 }
diff --git a/src/Codec/Picture/Jpg.hs b/src/Codec/Picture/Jpg.hs
@@ -423,8 +423,8 @@ decodeImage frame quants lst outImage = do
         maxiW = maximum [fst $ subSampling c | (c,_) <- params]
         maxiH = maximum [snd $ subSampling c | (c,_) <- params]
 
-        imageBlockWidth = (imgWidth + 7) `div` 8
-        imageBlockHeight = (imgHeight + 7) `div` 8
+        imageBlockWidth = toBlockSize imgWidth
+        imageBlockHeight = toBlockSize imgHeight
 
         imageMcuWidth = (imageBlockWidth + (maxiW - 1)) `div` maxiW
         imageMcuHeight = (imageBlockHeight + (maxiH - 1)) `div` maxiH

diff --git a/src/Codec/Picture/Jpg/Common.hs b/src/Codec/Picture/Jpg/Common.hs
@@ -17,6 +17,7 @@ module Codec.Picture.Jpg.Common
     , rasterMap
     , decodeMacroBlock
     , decodeRestartInterval
+    , toBlockSize
     ) where
 
 #if !MIN_VERSION_base(4,8,0)
@@ -53,13 +54,22 @@ data JpgUnpackerParameter = JpgUnpackerParameter
     , coefficientRange     :: !(Int, Int)
     , successiveApprox     :: !(Int, Int)
     , readerIndex          :: {-# UNPACK #-} !Int
+      -- | When in progressive mode, we can have many
+      -- color in a scan are 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.
     , indiceVector         :: {-# UNPACK #-} !Int
     , blockIndex           :: {-# UNPACK #-} !Int
     , blockMcuX            :: {-# UNPACK #-} !Int
     , blockMcuY            :: {-# UNPACK #-} !Int
     }
     deriving Show
 
+toBlockSize :: Int -> Int
+toBlockSize v = (v + 7) `div` 8
+
 decodeRestartInterval :: BoolReader s Int32
 decodeRestartInterval = return (-1) {-  do
   bits <- replicateM 8 getNextBitJpg
@@ -195,9 +205,9 @@ pixelClamp n = fromIntegral . min 255 $ max 0 n
 unpackMacroBlock :: Int    -- ^ Component count
                  -> Int -- ^ Width coefficient
                  -> Int -- ^ Height coefficient
+                 -> Int -- ^ Component index
                  -> Int -- ^ x
                  -> Int -- ^ y
-                 -> Int    -- ^ Component index
                  -> MutableImage s PixelYCbCr8
                  -> MutableMacroBlock s Int16
                  -> ST s ()

diff --git a/src/Codec/Picture/Jpg/Progressive.hs b/src/Codec/Picture/Jpg/Progressive.hs
@@ -36,12 +36,9 @@ createMcuLineIndices param imgWidth mcuWidth =
  V.fromList $ VS.fromList <$> [indexSolo, indexMulti]
   where compW = fromIntegral $ horizontalSamplingFactor param
         compH = fromIntegral $ verticalSamplingFactor param
-        imageBlockSize = (imgWidth + 7) `div` 8
-
-        indexSolo =
-            [y * mcuWidth * compW + x
-                | y <- [0 .. compH - 1], x <- [0 .. imageBlockSize - 1]]
+        imageBlockSize = toBlockSize imgWidth
 
+        indexSolo = take (imageBlockSize * compH) [0 ..]
         indexMulti = 
             [(mcu + y * mcuWidth) * compW + x
                 | mcu <- [0 .. mcuWidth - 1]
@@ -195,13 +192,13 @@ prepareUnpacker lst = do
                  selection _      _      = decodeRefineAc
 
 data ComponentData s = ComponentData
-    { componentIndices    :: V.Vector (VS.Vector Int)
-    , componentBlocks     :: V.Vector (MutableMacroBlock s Int16)
-    , componentId         :: !Int
-    , componentBlockCount :: !Int
-    }
+  { componentIndices    :: V.Vector (VS.Vector Int)
+  , componentBlocks     :: V.Vector (MutableMacroBlock s Int16)
+  , componentId         :: !Int
+  , componentBlockCount :: !Int
+  }
 
--- | Iteration from to n in monadic context, without data
+-- | Iteration from 0 to n in monadic context, without data
 -- keeping.
 lineMap :: (Monad m) => Int -> (Int -> m ()) -> m ()
 {-# INLINE lineMap #-}
@@ -259,6 +256,8 @@ progressiveUnpack (maxiW, maxiH) frame quants lst = do
             let componentNumber = componentIndex unpackParam
             writeIndex <- writeIndices `MS.read` componentNumber
             let componentData = allBlocks !! componentNumber
+                -- We get back the correct block indices for the number of component
+                -- in the current scope (precalculated)
                 indexVector =
                     componentIndices componentData ! indiceVector unpackParam
                 maxIndexLength = VS.length indexVector
@@ -305,14 +304,14 @@ progressiveUnpack (maxiW, maxiH) frame quants lst = do
         imgWidth = fromIntegral $ jpgWidth frame
         imgHeight = fromIntegral $ jpgHeight frame
 
-        imageBlockWidth = (imgWidth + 7) `div` 8
-        imageBlockHeight = (imgHeight + 7) `div` 8
+        imageBlockWidth = toBlockSize imgWidth
+        imageBlockHeight = toBlockSize imgHeight
 
-        imageMcuWidth = (imageBlockWidth + (maxiW - 1)) `div` maxiW
+        imageMcuWidth =  (imageBlockWidth + (maxiW - 1)) `div` maxiW
         imageMcuHeight = (imageBlockHeight + (maxiH - 1)) `div` maxiH
 
         allocateWorkingBlocks (ix, comp) = do
-            let blockCount = hSample * vSample * imageMcuWidth
+            let blockCount = hSample * vSample * imageMcuWidth * 2
             blocks <- V.replicateM blockCount createEmptyMutableMacroBlock
             return ComponentData 
                 { componentBlocks = blocks