addons update

git-svn-id: https://svn.code.sf.net/p/kolmck/code@67 91bb2d04-0c0c-4d2d-88a5-bbb6f4c1fa07

Addons/UBitTreeEncoder.pas

@@ -0,0 +1,116 @@
+unit UBitTreeEncoder;
+
+{$IFDEF FPC}
+{$MODE Delphi}
+{$ENDIF}
+
+interface
+
+uses KOL, URangeDecoder,URangeEncoder;
+
+type PBitTreeEncoder =^TBitTreeEncoder;
+     TBitTreeEncoder=object(TObj)
+       public
+         Models: array of smallint;
+         NumBitLevels:integer;
+         constructor Create(const AnumBitLevels:integer);
+         procedure _Init;
+         procedure Encode(const ArangeEncoder:PRangeEncoder;const Asymbol:integer);
+         procedure ReverseEncode(const ArangeEncoder:PRangeEncoder;Asymbol:integer);
+         function GetPrice(const Asymbol:integer):integer;
+         function ReverseGetPrice(Asymbol:integer):integer;overload;
+       end;
+
+procedure ReverseEncode(var AModels:array of smallint;const AstartIndex:integer;const ArangeEncoder:PRangeEncoder;const ANumBitLevels:integer; Asymbol:integer);
+function ReverseGetPrice(var AModels:array of smallint;const AstartIndex,ANumBitLevels:integer; Asymbol:integer):integer;
+
+implementation
+
+constructor TBitTreeEncoder.Create(const AnumBitLevels:integer);
+begin
+self.NumBitLevels:=AnumBitLevels;
+setlength(Models,1 shl AnumBitLevels);
+end;
+
+procedure TBitTreeEncoder._Init;
+begin
+URangeDecoder.InitBitModels(Models);
+end;
+
+procedure TBitTreeEncoder.Encode(const ArangeEncoder:PRangeEncoder;const Asymbol:integer);
+var m,bitindex,bit:integer;
+begin
+m := 1;
+for bitIndex := NumBitLevels -1 downto 0 do begin
+    bit := (Asymbol shr bitIndex) and 1;
+    ArangeEncoder.Encode(Models, m, bit);
+    m := (m shl 1) or bit;
+    end;
+end;
+
+procedure TBitTreeEncoder.ReverseEncode(const ArangeEncoder:PRangeEncoder;Asymbol:integer);
+var m,i,bit:integer;
+begin
+m:=1;
+for i:= 0 to NumBitLevels -1 do begin
+    bit := Asymbol and 1;
+    ArangeEncoder.Encode(Models, m, bit);
+    m := (m shl 1) or bit;
+    Asymbol := Asymbol shr 1;
+    end;
+end;
+
+function TBitTreeEncoder.GetPrice(const Asymbol:integer):integer;
+var price,m,bitindex,bit:integer;
+begin
+price := 0;
+m := 1;
+for bitIndex := NumBitLevels - 1 downto 0 do begin
+    bit := (Asymbol shr bitIndex) and 1;
+    price := price + RangeEncoder.GetPrice(Models[m], bit);
+    m := (m shl 1) + bit;
+    end;
+result:=price;
+end;
+
+function TBitTreeEncoder.ReverseGetPrice(Asymbol:integer):integer;
+var price,m,i,bit:integer;
+begin
+price := 0;
+m := 1;
+for i:= NumBitLevels downto 1 do begin
+    bit := Asymbol and 1;
+    Asymbol := Asymbol shr 1;
+    price :=price + RangeEncoder.GetPrice(Models[m], bit);
+    m := (m shl 1) or bit;
+    end;
+result:=price;
+end;
+
+function ReverseGetPrice(var AModels:array of smallint;const AstartIndex,ANumBitLevels:integer;Asymbol:integer):integer;
+var price,m,i,bit:integer;
+begin
+price := 0;
+m := 1;
+for i := ANumBitLevels downto 1 do begin
+    bit := Asymbol and 1;
+    Asymbol := Asymbol shr 1;
+    price := price + RangeEncoder.GetPrice(AModels[AstartIndex + m], bit);
+    m := (m shl 1) or bit;
+    end;
+result:=price;
+end;
+
+procedure ReverseEncode(var AModels:array of smallint;const AstartIndex:integer;const ArangeEncoder:PRangeEncoder;const ANumBitLevels:integer;Asymbol:integer);
+var m,i,bit:integer;
+begin
+m:=1;
+for i := 0 to ANumBitLevels -1 do begin
+    bit := Asymbol and 1;
+    ArangeEncoder.Encode(AModels, AstartIndex + m, bit);
+    m := (m shl 1) or bit;
+    Asymbol := Asymbol shr 1;
+    end;
+end;
+
+end.