Dirac - A Video Codec

Created by the British Broadcasting Corporation.


Public Member Functions | Protected Member Functions | Protected Attributes | Private Member Functions
dirac::GenericBandCodec< EntropyCodec > Class Template Reference

A template class for coding and decoding wavelet subband data.

#include <band_codec.h>

Inheritance diagram for dirac::GenericBandCodec< EntropyCodec >:
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List of all members.

Public Member Functions

 GenericBandCodec (SubbandByteIO *subband_byteio, size_t number_of_contexts, const SubbandList &band_list, int band_num, const bool is_intra)
 Constructor.

Protected Member Functions

void CodeVal (CoeffArray &in_data, const int xpos, const int ypos, const CoeffType val)
 Code an individual quantised value and perform inverse-quantisation.
void DecodeVal (CoeffArray &out_data, const int xpos, const int ypos)
 Decode an individual quantised value and perform inverse-quantisation.
void CodeQuantIndexOffset (const int offset)
 Encode the offset for a code block quantiser.
int DecodeQuantIndexOffset ()
 Decode the offset for a code block quantiser.
void SetToVal (const CodeBlock &code_block, CoeffArray &coeff_data, const CoeffType val)
 Set a code block area to a given value.
virtual void ClearBlock (const CodeBlock &code_block, CoeffArray &coeff_data)
 Set all block values to 0.
virtual void DoWorkCode (CoeffArray &in_data)
virtual void DoWorkDecode (CoeffArray &out_data)
virtual void CodeCoeffBlock (const CodeBlock &code_block, CoeffArray &in_data)
virtual void DecodeCoeffBlock (const CodeBlock &code_block, CoeffArray &out_data)
virtual void CodeCoeff (CoeffArray &in_data, const int xpos, const int ypos)
virtual void DecodeCoeff (CoeffArray &in_data, const int xpos, const int ypos)
int ChooseFollowContext (const int bin_number) const
 A function for choosing the context for "follow bits".
int ChooseInfoContext () const
 A function for choosing the context for "information bits".
int ChooseSignContext (const CoeffArray &data, const int xpos, const int ypos) const
 A function for choosing the context for sign bits.

Protected Attributes

bool m_is_intra
 Flag indicating whether the band comes from an intra picture.
int m_bnum
 variables
const Subband m_node
 the subband being coded
int m_last_qf_idx
 the quantisation index of the last codeblock
int m_qf
 quantisation value
CoeffType m_offset
 reconstruction point
bool m_nhood_nonzero
 True if neighbours non-zero.
Subband m_pnode
 the parent subband
int m_pxpos
 position of the parent coefficient
int m_pypos
bool m_parent_notzero
 True if the parent of a coeff is not zero.

Private Member Functions

 GenericBandCodec (const GenericBandCodec &cpy)
 Private, bodyless copy constructor: class should not be copied.
GenericBandCodecoperator= (const GenericBandCodec &rhs)
 Private, bodyless copy operator=: class should not be assigned.

Constructor & Destructor Documentation

template<typename EntropyCodec >
GenericBandCodec::GenericBandCodec ( SubbandByteIO subband_byteio,
size_t  number_of_contexts,
const SubbandList band_list,
int  band_num,
const bool  is_intra 
)

Constructor for encoding.

Creates a BandCodec object to encode subband data

Parameters:
subband_byteioinput/output for the encoded bits
number_of_contextsthe number of contexts used in the encoding process
band_listthe set of all the subbands
band_numthe number of the subband being coded
is_intraFlag indicating whether the band comes from an intra picture

References dirac::GenericBandCodec< EntropyCodec >::m_node, dirac::GenericBandCodec< EntropyCodec >::m_pnode, and dirac::Subband::Parent().

template<typename EntropyCodec>
dirac::GenericBandCodec< EntropyCodec >::GenericBandCodec ( const GenericBandCodec< EntropyCodec > &  cpy)
private

Member Function Documentation

template<typename EntropyCodec >
int GenericBandCodec::ChooseFollowContext ( const int  bin_number) const
inlineprotected
template<typename EntropyCodec >
int GenericBandCodec::ChooseInfoContext ( ) const
inlineprotected

References dirac::INFO_CTX.

template<typename EntropyCodec >
int GenericBandCodec::ChooseSignContext ( const CoeffArray data,
const int  xpos,
const int  ypos 
) const
inlineprotected
template<typename EntropyCodec >
void GenericBandCodec::ClearBlock ( const CodeBlock code_block,
CoeffArray coeff_data 
)
protectedvirtual
template<typename EntropyCodec >
void GenericBandCodec::CodeCoeff ( CoeffArray in_data,
const int  xpos,
const int  ypos 
)
protectedvirtual
template<typename EntropyCodec >
void GenericBandCodec::CodeCoeffBlock ( const CodeBlock code_block,
CoeffArray in_data 
)
protectedvirtual
template<typename EntropyCodec >
void GenericBandCodec::CodeQuantIndexOffset ( const int  offset)
protected
template<typename EntropyCodec >
void GenericBandCodec::CodeVal ( CoeffArray in_data,
const int  xpos,
const int  ypos,
const CoeffType  val 
)
inlineprotected
template<typename EntropyCodec >
void GenericBandCodec::DecodeCoeff ( CoeffArray in_data,
const int  xpos,
const int  ypos 
)
protectedvirtual

Reimplemented in dirac::IntraDCBandCodec.

template<typename EntropyCodec >
void GenericBandCodec::DecodeCoeffBlock ( const CodeBlock code_block,
CoeffArray out_data 
)
protectedvirtual
template<typename EntropyCodec >
int GenericBandCodec::DecodeQuantIndexOffset ( )
protected
template<typename EntropyCodec >
void GenericBandCodec::DecodeVal ( CoeffArray out_data,
const int  xpos,
const int  ypos 
)
inlineprotected
template<typename EntropyCodec >
void GenericBandCodec::DoWorkCode ( CoeffArray in_data)
protectedvirtual

Reimplemented in dirac::IntraDCBandCodec.

References dirac::BLOCK_SKIP_CTX.

template<typename EntropyCodec >
void GenericBandCodec::DoWorkDecode ( CoeffArray out_data)
protectedvirtual
template<typename EntropyCodec>
GenericBandCodec& dirac::GenericBandCodec< EntropyCodec >::operator= ( const GenericBandCodec< EntropyCodec > &  rhs)
private
template<typename EntropyCodec >
void GenericBandCodec::SetToVal ( const CodeBlock code_block,
CoeffArray coeff_data,
const CoeffType  val 
)
inlineprotected

Member Data Documentation

template<typename EntropyCodec>
int dirac::GenericBandCodec< EntropyCodec >::m_bnum
protected
template<typename EntropyCodec>
bool dirac::GenericBandCodec< EntropyCodec >::m_is_intra
protected
template<typename EntropyCodec>
int dirac::GenericBandCodec< EntropyCodec >::m_last_qf_idx
protected
template<typename EntropyCodec>
bool dirac::GenericBandCodec< EntropyCodec >::m_nhood_nonzero
protected
template<typename EntropyCodec>
const Subband dirac::GenericBandCodec< EntropyCodec >::m_node
protected
template<typename EntropyCodec>
CoeffType dirac::GenericBandCodec< EntropyCodec >::m_offset
protected
template<typename EntropyCodec>
bool dirac::GenericBandCodec< EntropyCodec >::m_parent_notzero
protected
template<typename EntropyCodec>
Subband dirac::GenericBandCodec< EntropyCodec >::m_pnode
protected
template<typename EntropyCodec>
int dirac::GenericBandCodec< EntropyCodec >::m_pxpos
protected
template<typename EntropyCodec>
int dirac::GenericBandCodec< EntropyCodec >::m_pypos
protected
template<typename EntropyCodec>
int dirac::GenericBandCodec< EntropyCodec >::m_qf
protected

The documentation for this class was generated from the following files:

© 2004 British Broadcasting Corporation. Dirac code licensed under the Mozilla Public License (MPL) Version 1.1.
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