factor: trim using lists

[factor.git] / basis / compression / run-length / run-length.factor

diff --git a/basis/compression/run-length/run-length.factor b/basis/compression/run-length/run-length.factor
index 65538605465183ca9a96c38967f4203c8defef37..15380d2ae1a60af67d327c175b7afc94f8a99199 100644 (file)
--- a/basis/compression/run-length/run-length.factor
+++ b/basis/compression/run-length/run-length.factor
@@ -1,7 +1,74 @@
 ! Copyright (C) 2009 Doug Coleman.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: arrays grouping sequences ;
+USING: arrays combinators grouping kernel math math.matrices
+math.order sequences sequences.parser ;
 IN: compression.run-length
 
 : run-length-uncompress ( byte-array -- byte-array' )
-    2 group [ first2 <array> ] map concat ;
+    2 group [ first2 <array> ] map B{ } concat-as ;
+
+: 8hi-lo ( byte -- hi lo )
+    [ 0xf0 bitand -4 shift ] [ 0xf bitand ] bi ; inline
+
+:: run-length-uncompress-bitmap4 ( byte-array m n -- byte-array' )
+    byte-array <sequence-parser> :> sp
+    m  1 + n <zero-matrix> :> matrix
+    n 4 mod n + :> stride
+    0 :> i!
+    0 :> j!
+    f :> done?!
+    [
+        ! i j [ number>string ] bi@ " " glue .
+        sp next dup 0 = [
+            sp next dup 0x03 0xff between? [
+                nip [ sp ] dip dup odd?
+                [ 1 + take-n but-last ] [ take-n ] if
+                [ j matrix i swap nth copy ] [ length j + j! ] bi
+            ] [
+                nip {
+                    { 0 [ i 1 + i!  0 j! ] }
+                    { 1 [ t done?! ] }
+                    { 2 [ sp next j + j!  sp next i + i! ] }
+                } case
+            ] if
+        ] [
+            [ sp next 8hi-lo 2array <repetition> concat ] [ head ] bi
+            [ j matrix i swap nth copy ] [ length j + j! ] bi
+        ] if
+
+        ! j stride >= [ i 1 + i!  0 j! ] when
+        j stride >= [ 0 j! ] when
+        done? not
+    ] loop
+    matrix B{ } concat-as ;
+
+:: run-length-uncompress-bitmap8 ( byte-array m n -- byte-array' )
+    byte-array <sequence-parser> :> sp
+    m  1 + n <zero-matrix> :> matrix
+    n 4 mod n + :> stride
+    0 :> i!
+    0 :> j!
+    f :> done?!
+    [
+        ! i j [ number>string ] bi@ " " glue .
+        sp next dup 0 = [
+            sp next dup 0x03 0xff between? [
+                nip [ sp ] dip dup odd?
+                [ 1 + take-n but-last ] [ take-n ] if
+                [ j matrix i swap nth copy ] [ length j + j! ] bi
+            ] [
+                nip {
+                    { 0 [ i 1 + i!  0 j! ] }
+                    { 1 [ t done?! ] }
+                    { 2 [ sp next j + j!  sp next i + i! ] }
+                } case
+            ] if
+        ] [
+            sp next <array> [ j matrix i swap nth copy ] [ length j + j! ] bi
+        ] if
+
+        ! j stride >= [ i 1 + i!  0 j! ] when
+        j stride >= [ 0 j! ] when
+        done? not
+    ] loop
+    matrix B{ } concat-as ;