comp_decompress.cpp

/* ***** BEGIN LICENSE BLOCK *****
*
* $Id: comp_decompress.cpp,v 1.2 2005/01/30 05:11:41 gabest Exp $ $Name:  $
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
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* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
* the specific language governing rights and limitations under the License.
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* The Original Code is BBC Research and Development code.
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* The Initial Developer of the Original Code is the British Broadcasting
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* Portions created by the Initial Developer are Copyright (C) 2004.
* All Rights Reserved.
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* Contributor(s): Thomas Davies (Original Author), Scott R Ladd
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#include <libdirac_decoder/comp_decompress.h>
#include <libdirac_common/wavelet_utils.h>
#include <libdirac_common/band_codec.h>
#include <libdirac_common/golomb.h>
using namespace dirac;

#include <vector>

#include <ctime>

using std::vector;

//Constructor
CompDecompressor::CompDecompressor( DecoderParams& decp, const FrameParams& fp)
:
m_qflist(60),
m_decparams(decp),
m_fparams(fp)
{}


void CompDecompressor::Decompress(PicArray& pic_data)
{
        const FrameSort& fsort=m_fparams.FSort();
        const int depth=4;
        BandCodec* bdecoder;
    const size_t CONTEXTS_REQUIRED = 24;
        Subband node;
        unsigned int max_bits;
        int qf_idx;

        WaveletTransform wtransform(depth);
        SubbandList& bands=wtransform.BandList();
        bands.Init(depth , pic_data.LengthX() , pic_data.LengthY());

        GenQuantList();

        for (int I=bands.Length();I>=1;--I)
        {

                //read the header data first
                qf_idx=GolombDecode( m_decparams.BitsIn() );
                if (qf_idx!=-1){
                        bands(I).SetQf(0,m_qflist[qf_idx]);
                        max_bits=UnsignedGolombDecode( m_decparams.BitsIn() );
                        m_decparams.BitsIn().FlushInput();

                        if (I>=bands.Length()){
                                if (fsort==I_frame && I==bands.Length())
                                        bdecoder=new IntraDCBandCodec( &m_decparams.BitsIn() , CONTEXTS_REQUIRED ,bands);
                                else
                                        bdecoder=new LFBandCodec( &m_decparams.BitsIn() , CONTEXTS_REQUIRED ,bands , I);
                        }
                        else
                                bdecoder=new BandCodec( &m_decparams.BitsIn() , CONTEXTS_REQUIRED , bands , I);

                        bdecoder->InitContexts();
                        bdecoder->Decompress(pic_data,max_bits);
                        delete bdecoder;
                }
                else{
                        m_decparams.BitsIn().FlushInput();
                        if (I==bands.Length() && fsort==I_frame)
                                SetToVal(pic_data,bands(I),2692);
                        else
                                SetToVal(pic_data,bands(I),0);
                }
        }
        wtransform.Transform(BACKWARD,pic_data);
}

void CompDecompressor::SetToVal(PicArray& pic_data,const Subband& node,ValueType val){
        for (int J=node.Yp();J<node.Yp()+node.Yl();++J)
        {       
                for (int I=node.Xp();I<node.Xp()+node.Xl();++I)
                {
                        pic_data[J][I]=val;
                }
        }
}

void CompDecompressor::GenQuantList(){//generates the list of quantisers and inverse quantisers
        //there is some repetition in this list but at the moment this is easiest from the perspective of SelectQuant
        //Need to remove this repetition later TJD 29 March 04.

        m_qflist[0]=1;          
        m_qflist[1]=1;          
        m_qflist[2]=1;          
        m_qflist[3]=1;          
        m_qflist[4]=2;          
        m_qflist[5]=2;          
        m_qflist[6]=2;          
        m_qflist[7]=3;          
        m_qflist[8]=4;          
        m_qflist[9]=4;          
        m_qflist[10]=5;         
        m_qflist[11]=6;         
        m_qflist[12]=8;         
        m_qflist[13]=9;         
        m_qflist[14]=11;                
        m_qflist[15]=13;                
        m_qflist[16]=16;                
        m_qflist[17]=19;                
        m_qflist[18]=22;                
        m_qflist[19]=26;                
        m_qflist[20]=32;                
        m_qflist[21]=38;                
        m_qflist[22]=45;                
        m_qflist[23]=53;                
        m_qflist[24]=64;                
        m_qflist[25]=76;                
        m_qflist[26]=90;                
        m_qflist[27]=107;               
        m_qflist[28]=128;               
        m_qflist[29]=152;               
        m_qflist[30]=181;               
        m_qflist[31]=215;               
        m_qflist[32]=256;               
        m_qflist[33]=304;               
        m_qflist[34]=362;               
        m_qflist[35]=430;               
        m_qflist[36]=512;               
        m_qflist[37]=608;               
        m_qflist[38]=724;               
        m_qflist[39]=861;               
        m_qflist[40]=1024;      
        m_qflist[41]=1217;      
        m_qflist[42]=1448;      
        m_qflist[43]=1722;      
        m_qflist[44]=2048;      
        m_qflist[45]=2435;      
        m_qflist[46]=2896;      
        m_qflist[47]=3444;      
        m_qflist[48]=4096;      
        m_qflist[49]=4870;      
        m_qflist[50]=5792;      
        m_qflist[51]=6888;      
        m_qflist[52]=8192;      
        m_qflist[53]=9741;      
        m_qflist[54]=11585;     
        m_qflist[55]=13777;     
        m_qflist[56]=16384;     
        m_qflist[57]=19483;     
        m_qflist[58]=23170;     
        m_qflist[59]=27554;             
}

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