Dirac - A Video Codec

Created by the British Broadcasting Corporation.

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dirac::FrameDecompressor Class Reference

Compress a single image frame. More...

#include <frame_decompress.h>

List of all members.

Public Member Functions

• FrameDecompressor (DecoderParams &decp, ChromaFormat cf, unsigned int vd)

  Constructor.
  

• ~FrameDecompressor ()

  Destructor.
  

• bool Decompress (ParseUnitByteIO &parseunit_byteio, FrameBuffer &my_buffer, int au_fnum)

  Decompress the next frame into the buffer.
  

• const FrameParams & GetFrameParams () const

  Returns the frame parameters of the current frame being decoded.
  

Private Member Functions

• FrameDecompressor (const FrameDecompressor &cpy)

  Copy constructor is private and body-less.
  

• FrameDecompressor & operator= (const FrameDecompressor &rhs)

  Assignment = is private and body-less.
  

• void CompDecompress (TransformByteIO *p_transform_byteio, FrameBuffer &my_buffer, int fnum, CompSort cs)

  Decodes component data.
  

• void SetMVBlocks ()

  Set the number of superblocks and blocks.
  

• void PushFrame (FrameBuffer &my_buffer)

  Add a frame to the frame buffer.
  

Private Attributes

• DecoderParams & m_decparams

  Parameters for the decompression, as provided in constructor.
  

• ChromaFormat m_cformat

  Chroma format of the frame being decompressed.
  

• bool m_skipped

  An indicator which is true if the frame has been skipped, false otherwise.
  

• bool m_use_global

  An indicator that is true if we use global motion vectors, false otherwise.
  

• bool m_use_block_mv

  An indicator that is true if we use block motion vectors, false otherwise.
  

• PredMode m_global_pred_mode

  Prediction mode to use if we only have global motion vectors.
  

• FrameParams m_fparams

  Current Frame Parameters.
  

• unsigned int m_video_depth

  Video depth of the frame being decompressed.
  

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Detailed Description

This class decompresses a single frame at a time, using parameters supplied at its construction. FrameDecompressor is used by SequenceDecompressor.

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Constructor & Destructor Documentation

dirac::FrameDecompressor::FrameDecompressor	(	DecoderParams &	decp,
		ChromaFormat	cf,
		unsigned int	vd
	)

Creates a FrameDecompressor with specific set of parameters the control the decompression process. It decodes motion data before decoding each component of the frame.

Parameters:

	decp	decoder parameters
	cf	the chroma format of the frame being decompressed
	vd	the video depth of the frame being decompressed

dirac::FrameDecompressor::~FrameDecompressor

(

)

Releases resources.

dirac::FrameDecompressor::FrameDecompressor

(

const FrameDecompressor &

cpy

)

[private]

Copy constructor is private and body-less. This class should not be copied.

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Member Function Documentation

void dirac::FrameDecompressor::CompDecompress	(	TransformByteIO *	p_transform_byteio,
		FrameBuffer &	my_buffer,
		int	fnum,
		CompSort	cs
	)			[private]

bool dirac::FrameDecompressor::Decompress	(	ParseUnitByteIO &	parseunit_byteio,
		FrameBuffer &	my_buffer,
		int	au_fnum
	)

Decompresses the next frame from the stream and place at the end of a frame buffer. Returns true if able to decode successfully, false otherwise

Parameters:

	parseunit_byteio	Frame info in Dirac-stream format
	my_buffer	picture buffer into which the frame is placed
	au_fnum	Current AccessUnit frame-number

const FrameParams& dirac::FrameDecompressor::GetFrameParams

(

)

const [inline]

FrameDecompressor& dirac::FrameDecompressor::operator=

(

const FrameDecompressor &

rhs

)

[private]

Assignment = is private and body-less. This class should not be assigned.

void dirac::FrameDecompressor::PushFrame

(

FrameBuffer &

my_buffer

)

[private]

void dirac::FrameDecompressor::SetMVBlocks

(

)

[private]

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Member Data Documentation

ChromaFormat dirac::FrameDecompressor::m_cformat [private]

DecoderParams& dirac::FrameDecompressor::m_decparams [private]

FrameParams dirac::FrameDecompressor::m_fparams [private]

PredMode dirac::FrameDecompressor::m_global_pred_mode [private]

bool dirac::FrameDecompressor::m_skipped [private]

bool dirac::FrameDecompressor::m_use_block_mv [private]

bool dirac::FrameDecompressor::m_use_global [private]

unsigned int dirac::FrameDecompressor::m_video_depth [private]

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

• frame_decompress.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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