From 0a115a51a316be6c36b8d59e9b9431978385a88a Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Thu, 3 Dec 2015 23:45:05 +0100
Subject: [PATCH 1/6] styled code a bit.

---
 src/Main.hs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/Main.hs b/src/Main.hs
index 402abd5..fed4a33 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -14,8 +14,8 @@ import System.IO (stdin)
 
 data Options = Options
              { srcFile :: String
-             , width :: Int
-             , height :: Int
+             , width   :: Int
+             , height  :: Int
              }
 
 options :: Parser Options
@@ -55,12 +55,12 @@ conv (fp@(PixelRGB8 fr fg fb),PixelRGB8 br bg bb) = printf "\x1b[48;2;%d;%d;%dm\
    where
      lumi :: Word8 -> Char
      lumi x
-          | x > 225 = '@'
-          | x > 180 = 'O'
-          | x > 150 = 'X'
-          | x > 50 = 'o'
-          | x > 25 = 'x'
-          | x > 10 = '.'
+          | x > 225   = '@'
+          | x > 180   = 'O'
+          | x > 150   = 'X'
+          | x > 50    = 'o'
+          | x > 25    = 'x'
+          | x > 10    = '.'
           | otherwise = ' '
 
 img2ascii :: ((PixelRGB8,PixelRGB8) -> String) -> (Image PixelRGB8,Image PixelRGB8) -> [[String]]

From d8509a45e19dac4aba8a688444bad4388742dcfc Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Sun, 6 Dec 2015 01:48:59 +0100
Subject: [PATCH 2/6] added flag for 256-color support for older terminals and
 screen

---
 rose_256.img | 40 ++++++++++++++++++++++++++++++++++++++++
 src/Main.hs  | 26 +++++++++++++++++++++++---
 2 files changed, 63 insertions(+), 3 deletions(-)
 create mode 100644 rose_256.img

diff --git a/rose_256.img b/rose_256.img
new file mode 100644
index 0000000..1c073d3
--- /dev/null
+++ b/rose_256.img
@@ -0,0 +1,40 @@
+                                                                                                    
+                                                                                                    
+                                                                                                    
+                                                                                                    
+                                                                                                    
+                                                                                                    
+                                                               ooo.                                 
+                                                           oo oooooo                                
+                                  oox                   ooooooooooooo                               
+                                 xxoooooooo.   oooooooooooooooooooooooo                             
+                                 ooooooooooooooooooooooooooooooooooooooo .                          
+                                 oooooooooooooooooxoooooooooooooooooooooooo                         
+                                oooooooooooooooooooooooooooooooooooooooooooooooooo                  
+                               oooooooooooooxxoooooooooxxoooooxooooooooooooooooox.                  
+                               ooooooooooooooooooooxxxoooooooooxoooooooooooooooxx                   
+                              ooooooooooooxoooxxxxxooxxxxxoooooooooxooooooooooxx                    
+                            .ooooooooooooxxoooxxxooxooxxxooooooxooooooooooooooxx                    
+                          oooooooooooooooooooxoooxxooxxxooxooooooooooxoooooooxxx                    
+                  .xooooooooooooooooooooooooooooooooooooooooooooooooxxooooooooxx                    
+                    xxxxooooooooooooooooooooooooooooooxxxxoooxoooooo.xooooooooox                    
+                     xxxooooooooooooooooooooooxooooxxxxoooooxoooooox xoooooooooo                    
+                      xxxxoooooooooooooooooooooooooooooooxooooooox.  ooooooxxoo                     
+                      .xooooooooooooooooooooooooooxoooxoooooooooxxxxoooooxxx.                       
+                       xxxxxooooooxooooooxx.oooooooxooooooooxxxxxxooooooxxxx                        
+                       xxxoxxxoooooxxoooooooxxxxxxxooox.xxxxooooooooooxxxxx                         
+                       xxxxxxxxxxoooxxxxxxxxoooooooooooooooooooxxoooxxxxx.                          
+                       xx..xxxxxxxxoxxxooooooooooooooooooooxxx..oooxxx..                            
+                            xxxxxxxxxx.xxxxxxxxxxx...xxxx......xoxxx..                              
+                            xxxxx.xxxxxx.........        ......xxx..                                
+                            ooooooooxxxxxx.........     .xx......                                   
+                            oooooooooooxxx...        .........                                      
+                           ooooooooooooooooooxx.......x....x..                                      
+                          oooooooooooooooooooooooooxx.......                                        
+                         ooxxxxxxxxxxxxxoooooooooooooo....                                          
+                            x...xxxxxxxxxxxxxxoooooxxxx.                                            
+                                 ...........xxxxooxxx.                                              
+                                               .xox                                                 
+                                                                                                    
+                                                                                                    
+                                                                                                    
diff --git a/src/Main.hs b/src/Main.hs
index fed4a33..918b70a 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -16,13 +16,15 @@ data Options = Options
              { srcFile :: String
              , width   :: Int
              , height  :: Int
+             , trueColor :: Bool
              }
 
 options :: Parser Options
 options = Options
         <$> argument str (metavar "SRC" <> help "source file (or - for stdin)")
         <*> argument auto (metavar "WIDTH" <> help "resulting width")
-        <*> argument auto (metavar "HEIGH" <> help "resulting height")
+        <*> argument auto (metavar "HEIGHT" <> help "resulting height")
+        <*> flag True False (long "256-colors" <> short 'c' <> help "only use 256-color-mode for old terminals")
 
 opthelp :: ParserInfo Options
 opthelp = info (helper <*> options)
@@ -35,7 +37,7 @@ main :: IO ()
 main = execParser opthelp >>= run
 
 run :: Options -> IO ()
-run (Options src w h) = do
+run (Options src w h c) = do
        src' <- if src == "-" then B.getContents else B.readFile src
        case decodeImage src' of
          Left err -> putStrLn err
@@ -43,7 +45,7 @@ run (Options src w h) = do
             case extractDynImage img >>= pixelize w h of
                  Nothing -> return ()
                  Just (f,b) ->
-                     let str = img2ascii conv (f,b)
+                     let str = if c then img2ascii conv (f,b) else img2ascii conv256 (f,b)
                       in mapM_ (\x -> putStr x >> putStrLn "\x1b[0m") (concat <$> str)
 
 chunksof :: Int -> [a] -> [[a]]
@@ -63,6 +65,24 @@ conv (fp@(PixelRGB8 fr fg fb),PixelRGB8 br bg bb) = printf "\x1b[48;2;%d;%d;%dm\
           | x > 10    = '.'
           | otherwise = ' '
 
+conv256 :: (PixelRGB8,PixelRGB8) -> String
+conv256 (fp@(PixelRGB8 fr fg fb),PixelRGB8 br bg bb) = printf "\x1b[48;5;%dm\x1b[38;5;%dm%c" bcolor fcolor (lumi.computeLuma $ fp)
+   where
+     -- converts [0..255] -> [0..5]
+     s = (`div` 51)
+     -- conversion: 6x6x6 rgb-cube so color is red * 36 + green * 6 + blue + 16 offset with red/green/blue in [0..5]
+     bcolor = s br * 36 + s bg * 6 + s bb + 16
+     fcolor = s fr * 36 + s fg * 6 + s fb + 16
+     lumi :: Word8 -> Char
+     lumi x
+          | x > 225   = '@'
+          | x > 180   = 'O'
+          | x > 150   = 'X'
+          | x > 50    = 'o'
+          | x > 25    = 'x'
+          | x > 10    = '.'
+          | otherwise = ' '
+
 img2ascii :: ((PixelRGB8,PixelRGB8) -> String) -> (Image PixelRGB8,Image PixelRGB8) -> [[String]]
 img2ascii c (fg@(Image w h _),bg@(Image w' h' _)) = (fmap.fmap) (c.(uncurry (pixelAt fg) &&& uncurry (pixelAt bg))) [[(x,y) | x <- [0..w-1]] | y <- [0..h-1]]
 

From 46ef59dde1806393bdcb511b2c9e909e2ba9e5ee Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Sun, 6 Dec 2015 01:55:16 +0100
Subject: [PATCH 3/6] switched from flag to switch in optparser

---
 src/Main.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Main.hs b/src/Main.hs
index 918b70a..03c517b 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -24,7 +24,7 @@ options = Options
         <$> argument str (metavar "SRC" <> help "source file (or - for stdin)")
         <*> argument auto (metavar "WIDTH" <> help "resulting width")
         <*> argument auto (metavar "HEIGHT" <> help "resulting height")
-        <*> flag True False (long "256-colors" <> short 'c' <> help "only use 256-color-mode for old terminals")
+        <*> switch (long "256-colors" <> short 'c' <> help "only use 256-color-mode for old terminals")
 
 opthelp :: ParserInfo Options
 opthelp = info (helper <*> options)

From da4f4352429646018d5e2f3efeb4485f11d7136a Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Sun, 6 Dec 2015 02:00:01 +0100
Subject: [PATCH 4/6] improved readme

---
 README.md | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 0851e89..c35f8a8 100644
--- a/README.md
+++ b/README.md
@@ -3,9 +3,13 @@ Image to ASCII-Converter
 
 # build instructions
 
-execute `stack build`. Result is then in your `.stack-work/dist/$system/$cabal/build/img2ascii/` folder. Replace `$system` and `$cabal` according to your installation.
+Execute `stack build`. Result is then in your `.stack-work/dist/$system/$cabal/build/img2ascii/` folder. Replace `$system` and `$cabal` according to your installation.
 
-Trhee example images in the resolution of 225x65, 225x65 and 100x40 are included. To view them just type `cat image1.img` in a suitable (aka TrueColor) terminal.
+Alternatively you can install the program with `stack install` to `~/.local/img2ascii` or for all users (if `stack install` is invoked as root).
+
+Three true-color example images in the resolution of 225x65, 225x65 and 100x40 are included. To view them just type `cat image1.img` in a suitable (aka TrueColor) terminal.
+
+One 256-color example is also included. Type `cat rose_256.img` to view that.
 
 # example
 

From d574d49f274691dc35ea96c1209046d69d3ea264 Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Mon, 7 Dec 2015 16:35:04 +0100
Subject: [PATCH 5/6] fixed foldl1-bug on empty list

---
 src/Main.hs | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/Main.hs b/src/Main.hs
index 03c517b..b68635e 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -4,7 +4,7 @@ import Codec.Picture
 import Codec.Picture.Types
 import Data.Maybe (fromJust)
 import Data.Word (Word8)
-import Data.List (transpose)
+import Data.List as L (transpose,foldl')
 import Text.Printf (printf)
 import Control.Arrow ((&&&))
 import Options.Applicative
@@ -97,16 +97,17 @@ pixelize tw th im@(Image iw ih id) =
        windowh = fromIntegral ih / fromIntegral th
 
 folder :: ((PixelRGB8, Int, Int) -> (PixelRGB8, Int, Int) -> (PixelRGB8, Int, Int)) -> Double -> Double -> Image PixelRGB8 -> Int -> Int -> (Image PixelRGB8, PixelRGB8)
-folder f ww wh im@(Image iw ih id) x y = (im,(\(a,_,_) -> a) $ foldl1 f
+folder f ww wh im@(Image iw ih id) x y = (im,(\(a,_,_) -> a) $ L.foldl' f (pixelAt im x' y',0,0)
     [ (pixelAt im (x'+dx) (y'+dy),dx,dy)
-    | dx <- [-(floor $ ww / 2)..(floor $ ww*0.5)]
-    , dy <- [-(floor $ ww / 2)..(floor $ ww*0.5)]
+    | dx <- [-dw..dw]
+    , dy <- [-dw..dw]
     , x'+dx > 0 && x'+dx < iw
     , y'+dy > 0 && y'+dy < ih
     ])
     where
-     x' = floor $ fromIntegral x *ww
-     y' = floor $ fromIntegral y *wh
+     dw = floor $ ww
+     x' = floor $ fromIntegral x * ww
+     y' = floor $ fromIntegral y * wh
 
 filterfun :: (PixelRGB8,Int,Int) -> (PixelRGB8, Int, Int) -> (PixelRGB8,Int,Int)
 filterfun (x@(PixelRGB8 r g b),_,_) (y@(PixelRGB8 r' g' b'),_,_) = if computeLuma x > computeLuma y then (x,0,0) else (y,0,0)

From a4380981f2297137779b9e0a78a8db1eaa8592db Mon Sep 17 00:00:00 2001
From: Stefan Dresselhaus <sdressel@techfak.uni-bielefeld.de>
Date: Wed, 16 Dec 2015 00:35:12 +0100
Subject: [PATCH 6/6] changed meaning of 256-color flag to match the
 description

---
 src/Main.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Main.hs b/src/Main.hs
index b68635e..68fec21 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -37,7 +37,7 @@ main :: IO ()
 main = execParser opthelp >>= run
 
 run :: Options -> IO ()
-run (Options src w h c) = do
+run (Options src w h redcol) = do
        src' <- if src == "-" then B.getContents else B.readFile src
        case decodeImage src' of
          Left err -> putStrLn err
@@ -45,7 +45,7 @@ run (Options src w h c) = do
             case extractDynImage img >>= pixelize w h of
                  Nothing -> return ()
                  Just (f,b) ->
-                     let str = if c then img2ascii conv (f,b) else img2ascii conv256 (f,b)
+                     let str = if redcol then img2ascii conv256 (f,b) else img2ascii conv (f,b)
                       in mapM_ (\x -> putStr x >> putStrLn "\x1b[0m") (concat <$> str)
 
 chunksof :: Int -> [a] -> [[a]]