Dirac - A Video Codec

Created by the British Broadcasting Corporation.


Public Member Functions | Protected Member Functions | List of all members
dirac::GenericIntraDCBandCodec< EntropyCodec > Class Template Reference

A template class specially for coding the DC subband of Intra frames.

#include <band_codec.h>

Inheritance diagram for dirac::GenericIntraDCBandCodec< EntropyCodec >:
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Collaboration diagram for dirac::GenericIntraDCBandCodec< EntropyCodec >:
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Public Member Functions

 GenericIntraDCBandCodec (SubbandByteIO *subband_byteio, size_t number_of_contexts, const SubbandList &band_list)
 Constructor. More...
 
- Public Member Functions inherited from dirac::GenericBandCodec< EntropyCodec >
 GenericBandCodec (SubbandByteIO *subband_byteio, size_t number_of_contexts, const SubbandList &band_list, int band_num, const bool is_intra)
 Constructor. More...
 

Protected Member Functions

void ClearBlock (const CodeBlock &code_block, CoeffArray &coeff_data)
 When coding a skipped block, propegate the predicted values for future non skipped blocks. More...
 
CoeffType GetPrediction (const CoeffArray &data, const int xpos, const int ypos) const
 Prediction of a DC value from its previously coded neighbours. More...
 
void DecodeCoeffBlock (const CodeBlock &code_block, CoeffArray &out_data)
 Decode codeblock of coefficients and perform DC prediction. More...
 
- Protected Member Functions inherited from dirac::GenericBandCodec< EntropyCodec >
void CodeVal (CoeffArray &in_data, const int xpos, const int ypos, const CoeffType val)
 Code an individual quantised value and perform inverse-quantisation. More...
 
void DecodeVal (CoeffArray &out_data, const int xpos, const int ypos)
 Decode an individual quantised value and perform inverse-quantisation. More...
 
void CodeQuantIndexOffset (const int offset)
 Encode the offset for a code block quantiser. More...
 
int DecodeQuantIndexOffset ()
 Decode the offset for a code block quantiser. More...
 
void SetToVal (const CodeBlock &code_block, CoeffArray &coeff_data, const CoeffType val)
 Set a code block area to a given value. More...
 
virtual void ClearBlock (const CodeBlock &code_block, CoeffArray &coeff_data)
 Set all block values to 0. More...
 
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". More...
 
int ChooseInfoContext () const
 A function for choosing the context for "information bits". More...
 
int ChooseSignContext (const CoeffArray &data, const int xpos, const int ypos) const
 A function for choosing the context for sign bits. More...
 

Additional Inherited Members

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

Constructor & Destructor Documentation

◆ GenericIntraDCBandCodec()

template<typename EntropyCodec >
dirac::GenericIntraDCBandCodec< EntropyCodec >::GenericIntraDCBandCodec ( SubbandByteIO subband_byteio,
size_t  number_of_contexts,
const SubbandList band_list 
)
inline

Creates a IntraDCBandCodec 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

Member Function Documentation

◆ ClearBlock()

template<typename EntropyCodec >
void GenericIntraDCBandCodec::ClearBlock ( const CodeBlock code_block,
CoeffArray coeff_data 
)
protectedvirtual

◆ DecodeCoeffBlock()

template<typename EntropyCodec >
void GenericIntraDCBandCodec::DecodeCoeffBlock ( const CodeBlock code_block,
CoeffArray out_data 
)
protectedvirtual

◆ GetPrediction()

template<typename EntropyCodec >
CoeffType GenericIntraDCBandCodec::GetPrediction ( const CoeffArray data,
const int  xpos,
const int  ypos 
) const
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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