Created by the British Broadcasting Corporation.
00001 /* ***** BEGIN LICENSE BLOCK ***** 00002 * 00003 * $Id: band_codec.h,v 1.36 2009/01/21 05:18:09 asuraparaju Exp $ $Name: Dirac_1_0_2 $ 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), 00024 * Scott R Ladd, 00025 * Steve Bearcroft 00026 * Andrew Kennedy 00027 * 00028 * Alternatively, the contents of this file may be used under the terms of 00029 * the GNU General Public License Version 2 (the "GPL"), or the GNU Lesser 00030 * Public License Version 2.1 (the "LGPL"), in which case the provisions of 00031 * the GPL or the LGPL are applicable instead of those above. If you wish to 00032 * allow use of your version of this file only under the terms of the either 00033 * the GPL or LGPL and not to allow others to use your version of this file 00034 * under the MPL, indicate your decision by deleting the provisions above 00035 * and replace them with the notice and other provisions required by the GPL 00036 * or LGPL. If you do not delete the provisions above, a recipient may use 00037 * your version of this file under the terms of any one of the MPL, the GPL 00038 * or the LGPL. 00039 * ***** END LICENSE BLOCK ***** */ 00040 00041 #ifndef _BAND_CODEC_H_ 00042 #define _BAND_CODEC_H_ 00043 00044 #include <libdirac_common/arith_codec.h> 00045 #include <libdirac_common/wavelet_utils.h> 00046 00047 00048 namespace dirac 00049 { 00050 00051 class SubbandByteIO; 00052 00053 //Subclasses the arithmetic codec to produce a coding/decoding tool for subbands 00054 00055 00057 template<typename EntropyCodec> 00058 class GenericBandCodec: public EntropyCodec 00059 { 00060 public: 00061 00063 00071 GenericBandCodec(SubbandByteIO* subband_byteio, 00072 size_t number_of_contexts, 00073 const SubbandList& band_list, 00074 int band_num, 00075 const bool is_intra); 00076 00077 protected: 00079 inline void CodeVal( CoeffArray& in_data , const int xpos , const int ypos , const CoeffType val); 00080 00082 inline void DecodeVal(CoeffArray& out_data , const int xpos , const int ypos ); 00083 00085 void CodeQuantIndexOffset( const int offset ); 00086 00088 int DecodeQuantIndexOffset(); 00089 00091 inline void SetToVal( const CodeBlock& code_block , CoeffArray& coeff_data , const CoeffType val); 00092 00094 virtual void ClearBlock( const CodeBlock& code_block , CoeffArray& coeff_data); 00095 00096 protected: 00097 //functions 00098 // Overridden from the base class 00099 virtual void DoWorkCode(CoeffArray& in_data); 00100 // Ditto 00101 virtual void DoWorkDecode(CoeffArray& out_data); 00102 00103 virtual void CodeCoeffBlock(const CodeBlock& code_block , CoeffArray& in_data); 00104 virtual void DecodeCoeffBlock(const CodeBlock& code_block , CoeffArray& out_data); 00105 00106 virtual void CodeCoeff(CoeffArray& in_data, const int xpos, const int ypos); 00107 00108 virtual void DecodeCoeff(CoeffArray& in_data, const int xpos, const int ypos); 00110 inline int ChooseFollowContext( const int bin_number ) const; 00111 00113 inline int ChooseInfoContext() const; 00114 00116 inline int ChooseSignContext(const CoeffArray& data , const int xpos , const int ypos ) const; 00117 00118 private: 00120 GenericBandCodec(const GenericBandCodec& cpy); 00122 GenericBandCodec& operator=(const GenericBandCodec& rhs); 00123 00124 protected: 00125 00127 bool m_is_intra; 00128 00130 int m_bnum; 00131 00133 const Subband m_node; 00134 00136 int m_last_qf_idx; 00137 00139 int m_qf; 00140 00142 CoeffType m_offset; 00143 00145 bool m_nhood_nonzero; 00146 00148 Subband m_pnode; 00149 00151 int m_pxpos, m_pypos; 00152 00154 bool m_parent_notzero; 00155 00156 }; 00157 00159 00162 typedef GenericBandCodec<ArithCodec<CoeffArray> > BandCodec; 00163 typedef BandCodec LFBandCodec; 00164 00166 //Finally,special class incorporating prediction for the DC band of intra frames// 00168 00170 template<typename EntropyCodec> 00171 class GenericIntraDCBandCodec : public GenericBandCodec<EntropyCodec> 00172 { 00173 public: 00175 00181 GenericIntraDCBandCodec(SubbandByteIO* subband_byteio, 00182 size_t number_of_contexts, 00183 const SubbandList& band_list) 00184 : GenericBandCodec<EntropyCodec>(subband_byteio,number_of_contexts, 00185 band_list, band_list.Length(), 00186 true){} 00187 00188 protected: 00190 void ClearBlock( const CodeBlock& code_block , CoeffArray& coeff_data); 00191 00193 CoeffType GetPrediction(const CoeffArray& data , const int xpos , const int ypos ) const; 00194 00196 void DecodeCoeffBlock(const CodeBlock& code_block , CoeffArray& out_data); 00197 }; 00198 00199 00201 00206 class IntraDCBandCodec: public GenericIntraDCBandCodec<ArithCodec<CoeffArray> > 00207 { 00208 public: 00210 00216 IntraDCBandCodec(SubbandByteIO* subband_byteio, 00217 size_t number_of_contexts, 00218 const SubbandList& band_list) 00219 : GenericIntraDCBandCodec<ArithCodec<CoeffArray> >(subband_byteio, 00220 number_of_contexts, 00221 band_list){} 00222 00223 00224 private: 00226 void DoWorkCode(CoeffArray& in_data); //overridden from the base class 00227 00229 void DoWorkDecode(CoeffArray& out_data); 00230 00232 void CodeCoeff(CoeffArray& in_data, const int xpos, const int ypos); 00233 00235 void DecodeCoeff(CoeffArray& out_data, const int xpos, const int ypos); 00236 00238 IntraDCBandCodec(const IntraDCBandCodec& cpy); 00239 00241 IntraDCBandCodec& operator=(const IntraDCBandCodec& rhs); 00242 00243 private: 00244 CoeffArray m_dc_pred_res; 00245 }; 00246 00247 }// end namespace dirac 00248 #endif
© 2004 British Broadcasting Corporation.
Dirac code licensed under the Mozilla Public License (MPL) Version 1.1.
HTML documentation generated by Dimitri van Heesch's
excellent Doxygen tool.