Dirac - A Video Codec

Created by the British Broadcasting Corporation.


band_codec.h

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00001 /* ***** BEGIN LICENSE BLOCK *****
00002 *
00003 * $Id: band_codec.h,v 1.11 2005/02/15 11:15:32 asuraparaju Exp $ $Name: Dirac_0_5_1 $
00004 *
00005 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00006 *
00007 * The contents of this file are subject to the Mozilla Public License
00008 * Version 1.1 (the "License"); you may not use this file except in compliance
00009 * with the License. You may obtain a copy of the License at
00010 * http://www.mozilla.org/MPL/
00011 *
00012 * Software distributed under the License is distributed on an "AS IS" basis,
00013 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
00014 * the specific language governing rights and limitations under the License.
00015 *
00016 * The Original Code is BBC Research and Development code.
00017 *
00018 * The Initial Developer of the Original Code is the British Broadcasting
00019 * Corporation.
00020 * Portions created by the Initial Developer are Copyright (C) 2004.
00021 * All Rights Reserved.
00022 *
00023 * Contributor(s): Thomas Davies (Original Author), Scott R Ladd
00024 *
00025 * Alternatively, the contents of this file may be used under the terms of
00026 * the GNU General Public License Version 2 (the "GPL"), or the GNU Lesser
00027 * Public License Version 2.1 (the "LGPL"), in which case the provisions of
00028 * the GPL or the LGPL are applicable instead of those above. If you wish to
00029 * allow use of your version of this file only under the terms of the either
00030 * the GPL or LGPL and not to allow others to use your version of this file
00031 * under the MPL, indicate your decision by deleting the provisions above
00032 * and replace them with the notice and other provisions required by the GPL
00033 * or LGPL. If you do not delete the provisions above, a recipient may use
00034 * your version of this file under the terms of any one of the MPL, the GPL
00035 * or the LGPL.
00036 * ***** END LICENSE BLOCK ***** */
00037 
00038 #ifndef _BAND_CODEC_H_
00039 #define _BAND_CODEC_H_
00040 
00041 #include <libdirac_common/arith_codec.h>
00042 #include <libdirac_common/wavelet_utils.h>
00043 
00044 namespace dirac
00045 {
00046 
00047     //Subclasses the arithmetic codec to produce a coding/decoding tool for subbands
00048 
00049 
00051 
00054     class BandCodec: public ArithCodec<PicArray >
00055     {
00056     public:
00057 
00059 
00066         BandCodec(BasicOutputManager* bits_out,
00067                   size_t number_of_contexts,
00068                   const SubbandList& band_list,
00069                   int band_num);
00070 
00072 
00079         BandCodec(BitInputManager* bits_in,
00080                   size_t number_of_contexts,
00081                   const SubbandList& band_list,
00082                   int band_num);
00083 
00085         void InitContexts();
00086 
00087     protected:
00089         void CodeVal( PicArray& in_data , const int xpos , const int ypos , const ValueType val);
00090 
00092         void DecodeVal(PicArray& out_data , const int xpos , const int ypos );
00093 
00095         void SetToVal( const CodeBlock& code_block , PicArray& pic_data , const ValueType val);
00096 
00097     private:
00098         //functions
00099         // Overridden from the base class
00100         virtual void DoWorkCode(PicArray& in_data);
00101         // Ditto
00102         virtual void DoWorkDecode(PicArray& out_data);
00103 
00104         virtual void CodeCoeffBlock(const CodeBlock& code_block , PicArray& in_data);
00105         virtual void DecodeCoeffBlock(const CodeBlock& code_block , PicArray& out_data);
00106 
00107         void Update( const bool symbol , const int context_num );
00108         void ResetAll();
00109     
00110         int ChooseContext( const int bin_number) const;
00111         int ChooseSignContext(const PicArray& data , const int xpos , const int ypos ) const;
00112 
00114         BandCodec(const BandCodec& cpy);
00116         BandCodec& operator=(const BandCodec& rhs);
00117 
00118     protected:
00120         int m_bnum;
00121 
00123         const Subband m_node;
00124     
00126         int m_vol;
00127     
00129         int m_reset_coeff_num;
00130     
00132         int m_coeff_count;
00133     
00135         int m_qf, m_qfinv;
00136     
00138         ValueType m_offset;
00139     
00141         ValueType m_nhood_sum;
00142     
00144         Subband m_pnode;
00145     
00147         int m_pxp, m_pyp, m_pxl, m_pyl;
00148     
00150         int m_pxpos, m_pypos;
00151     
00153         bool m_parent_notzero;
00154     
00156         ValueType m_cut_off_point;
00157     };
00158 
00160 
00164     class LFBandCodec: public BandCodec
00165     {
00166     public:
00168 
00175         LFBandCodec(BasicOutputManager* bits_out,
00176                     size_t number_of_contexts,
00177                     const SubbandList& band_list,
00178                     int band_num)
00179               : BandCodec(bits_out,number_of_contexts,band_list,band_num){}
00180 
00182 
00189         LFBandCodec(BitInputManager* bits_in,
00190                     size_t number_of_contexts,
00191                     const SubbandList& band_list,
00192                     int band_num)
00193           : BandCodec(bits_in,number_of_contexts,band_list,band_num){}
00194 
00195     private:
00196         // Overridden from the base class
00197         void DoWorkCode(PicArray& in_data);
00198         // Ditto
00199         void DoWorkDecode(PicArray& out_data);
00200 
00201         void CodeCoeffBlock(const CodeBlock& code_block , PicArray& in_data);
00202         void DecodeCoeffBlock(const CodeBlock& code_block , PicArray& out_data);
00203 
00205         LFBandCodec(const LFBandCodec& cpy);
00207         LFBandCodec& operator=(const LFBandCodec& rhs);
00208 
00209     };
00210 
00211 
00213     //Finally,special class incorporating prediction for the DC band of intra frames//
00215 
00217 
00221     class IntraDCBandCodec: public BandCodec
00222     {
00223     public:
00225 
00231         IntraDCBandCodec(BasicOutputManager* bits_out,
00232                          size_t number_of_contexts,
00233                          const SubbandList& band_list)
00234           : BandCodec(bits_out,number_of_contexts,band_list,band_list.Length()){}
00235 
00237 
00243         IntraDCBandCodec(BitInputManager* bits_in,
00244                          size_t number_of_contexts,
00245                          const SubbandList& band_list)
00246           : BandCodec(bits_in,number_of_contexts,band_list,band_list.Length()){}
00247 
00248     private:
00249         void DoWorkCode(PicArray& in_data);                    //overridden from the base class
00250         void DoWorkDecode(PicArray& out_data); //ditto
00251 
00252         void CodeCoeffBlock(const CodeBlock& code_block , PicArray& in_data);
00253         void DecodeCoeffBlock(const CodeBlock& code_block , PicArray& out_data);
00254 
00256         IntraDCBandCodec(const IntraDCBandCodec& cpy); 
00257 
00259         IntraDCBandCodec& operator=(const IntraDCBandCodec& rhs);
00260 
00262         ValueType GetPrediction(const PicArray& data , const int xpos , const int ypos ) const;
00263 
00264     private:
00265         PicArray m_dc_pred_res;
00266     };
00267 
00268 
00269 }// end namespace dirac
00270 #endif

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