Dirac - A Video Codec

Created by the British Broadcasting Corporation.

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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 >:

[legend]Collaboration diagram for dirac::GenericBandCodec< EntropyCodec >:

[legend]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

  position of the parent coefficient
  

• 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.
  

• GenericBandCodec & operator= (const GenericBandCodec &rhs)

  Private, bodyless copy operator=: class should not be assigned.
  

template<typename EntropyCodec>
class dirac::GenericBandCodec< EntropyCodec >

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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 )

Creates a BandCodec object to encode subband data Parameters: subband_byteio  input/output for the encoded bits number_of_contexts  the number of contexts used in the encoding process band_list  the set of all the subbands band_num  the number of the subband being coded is_intra  Flag indicating whether the band comes from an intra picture

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

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Member Function Documentation

template<typename EntropyCodec> int GenericBandCodec::ChooseFollowContext (  const int  bin_number  )  const [inline, protected]

template<typename EntropyCodec> int GenericBandCodec::ChooseInfoContext (   )  const [inline, protected]

template<typename EntropyCodec> int GenericBandCodec::ChooseSignContext (  const CoeffArray &  data, const int  xpos, const int  ypos )  const [inline, protected]

template<typename EntropyCodec> void GenericBandCodec::ClearBlock (  const CodeBlock &  code_block, CoeffArray &  coeff_data )  [protected, virtual]

Reimplemented in dirac::GenericIntraDCBandCodec< EntropyCodec >, dirac::GenericIntraDCBandCodec< ArithCodec< CoeffArray > >, and dirac::GenericIntraDCBandCodec< ArithCodecToVLCAdapter >.

template<typename EntropyCodec> void GenericBandCodec::CodeCoeff (  CoeffArray &  in_data, const int  xpos, const int  ypos )  [protected, virtual]

Reimplemented in dirac::IntraDCBandCodec, and dirac::IntraDCBandVLC.

template<typename EntropyCodec> void GenericBandCodec::CodeCoeffBlock (  const CodeBlock &  code_block, CoeffArray &  in_data )  [protected, virtual]

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 )  [inline, protected]

template<typename EntropyCodec> void GenericBandCodec::DecodeCoeff (  CoeffArray &  in_data, const int  xpos, const int  ypos )  [protected, virtual]

Reimplemented in dirac::IntraDCBandCodec.

template<typename EntropyCodec> void GenericBandCodec::DecodeCoeffBlock (  const CodeBlock &  code_block, CoeffArray &  out_data )  [protected, virtual]

Reimplemented in dirac::GenericIntraDCBandCodec< EntropyCodec >, dirac::GenericIntraDCBandCodec< ArithCodec< CoeffArray > >, and dirac::GenericIntraDCBandCodec< ArithCodecToVLCAdapter >.

template<typename EntropyCodec> int GenericBandCodec::DecodeQuantIndexOffset (   )  [protected]

template<typename EntropyCodec> void GenericBandCodec::DecodeVal (  CoeffArray &  out_data, const int  xpos, const int  ypos )  [inline, protected]

template<typename EntropyCodec> void GenericBandCodec::DoWorkCode (  CoeffArray &  in_data  )  [protected, virtual]

Reimplemented in dirac::IntraDCBandCodec.

template<typename EntropyCodec> void GenericBandCodec::DoWorkDecode (  CoeffArray &  out_data  )  [protected, virtual]

Reimplemented in dirac::IntraDCBandCodec.

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 )  [inline, protected]

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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]

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

• band_codec.h
• band_codec_template.h

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