Dirac - A Video Codec

Created by the British Broadcasting Corporation.

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dirac::ByteIO Class Reference

Class ByteIO - top-level class for reading/writing bytes to a stream.

#include <byteio.h>

Inheritance diagram for dirac::ByteIO:

List of all members.

Public Member Functions

• ByteIO (bool new_stream=true)

  Default constructor.
  

• ByteIO (const ByteIO &stream_data)

  Constructor.
  

• virtual ~ByteIO ()

  Destructor.
  

• virtual void CollateByteStats (DiracByteStats &dirac_byte_stats)

  Gathers byte-stream statistics.
  

• virtual const std::string GetBytes ()

  Get bytes in Dirac-bytestream format.
  

• int GetReadBytePosition () const

  Get position of read stream pointer.
  

• virtual int GetSize () const

  Gets size (in bytes).
  

• void SetByteParams (const ByteIO &byte_io)

  Copies stream source/destination info.
  

• void ByteAlignOutput ()

  Sync input for byte-alignment.
  

• void OutputVarLengthUint (const unsigned int &value)

  Ouputs an unsigned integer in interleaved exp Golomb format.
  

Protected Member Functions

• bool CanRead () const
• bool GetBit (unsigned char &c, int pos) const
• void SetBit (unsigned char &c, int pos) const
• void SetBits (unsigned char &c, unsigned char bits) const
• void ByteAlignInput ()

  Sync input for byte-alignment.
  

• bool InputBit ()

  Reads next bit.
  

• void InputBytes (char *data, int count)

  Reads from stream.
  

• int InputVarLengthInt ()

  Reads an integer in interleaved exp-Golomb format return Signed integer read.
  

• unsigned int InputVarLengthUint ()

  Reads an unsigned integer in interleaved exp Golomb format.
  

• unsigned int InputFixedLengthUint (const int byte_size)

  Reads a fixed length unsigned integer from the stream in big endian.
  

• unsigned char InputUnByte ()

  Reads a byte from the stream.
  

• std::string InputUnString (const int count)

  Reads a series of bytes from a stream.
  

• void OutputBit (const bool &bit)

  Outputs a bit.
  

• void OutputBytes (const std::string &bytes)

  Outputs a series of bytes.
  

• void OutputCurrentByte ()

  Outputs current byte contents.
  

• void OutputVarLengthInt (const int val)

  Outputs an integer in Golomb signed integer format.
  

• void OutputFixedLengthUint (const unsigned int &value, const int &length)

  Output unsigned int value in big endian format.
  

• void RemoveRedundantBytes (const int count)

  Removes portion of byte-stream no longer required.
  

• void SeekGet (const int offset, std::ios_base::seekdir dir)

Protected Attributes

• std::stringstream * mp_stream

  Input/output steam.
  

Private Attributes

• unsigned char m_current_byte

  Char used for temporary storage of op data bits.
  

• int m_current_pos

  Used to set individual bit within the current header byte.
  

• int m_num_bytes

  Number of bytes processed.
  

• bool m_new_stream

  stream alloc flag
  

Friends

• class ArithCodecBase

  ArithCodec can see internals for getting/setting bits.
  

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Constructor & Destructor Documentation

dirac::ByteIO::ByteIO

(

bool

new_stream = true

)

Parameters:

new_stream

Has Creates & owns data buffer

dirac::ByteIO::ByteIO

(

const ByteIO &

stream_data

)

Parameters:

stream_data

Copies data buffer details

virtual dirac::ByteIO::~ByteIO

(

)

[virtual]

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Member Function Documentation

void dirac::ByteIO::ByteAlignInput

(

)

[protected]

void dirac::ByteIO::ByteAlignOutput

(

)

bool dirac::ByteIO::CanRead

(

)

const [inline, protected]

virtual void dirac::ByteIO::CollateByteStats

(

DiracByteStats &

dirac_byte_stats

)

[inline, virtual]

Parameters:

dirac_byte_stats

Collates byte information

Reimplemented in dirac::ComponentByteIO, dirac::FrameByteIO, dirac::MvDataByteIO, dirac::ParseUnitByteIO, and dirac::TransformByteIO.

bool dirac::ByteIO::GetBit	(	unsigned char &	c,
		int	pos
	)			const [inline, protected]

virtual const std::string dirac::ByteIO::GetBytes

(

)

[virtual]

Reimplemented in dirac::DiracByteStream, dirac::FrameByteIO, dirac::MvDataByteIO, dirac::ParseUnitByteIO, dirac::SubbandByteIO, and dirac::TransformByteIO.

int dirac::ByteIO::GetReadBytePosition

(

)

const [inline]

virtual int dirac::ByteIO::GetSize

(

)

const [virtual]

Reimplemented in dirac::AccessUnitByteIO, dirac::FrameByteIO, dirac::MvDataByteIO, dirac::ParseUnitByteIO, and dirac::TransformByteIO.

bool dirac::ByteIO::InputBit

(

)

[protected]

void dirac::ByteIO::InputBytes	(	char *	data,
		int	count
	)			[inline, protected]

Parameters:

	data	Start of char buffer
	count	Number of bytes to read

unsigned int dirac::ByteIO::InputFixedLengthUint

(

const int

byte_size

)

[inline, protected]

Parameters:

byte_size

Number of bytes in fixed length integer

Returns:

Unsigned Integer read

unsigned char dirac::ByteIO::InputUnByte

(

)

[inline, protected]

std::string dirac::ByteIO::InputUnString

(

const int

count

)

[inline, protected]

int dirac::ByteIO::InputVarLengthInt

(

)

[protected]

unsigned int dirac::ByteIO::InputVarLengthUint

(

)

[protected]

Returns:

Unsigned Integer read

void dirac::ByteIO::OutputBit

(

const bool &

bit

)

[protected]

Parameters:

bit

1/0 Output

void dirac::ByteIO::OutputBytes

(

const std::string &

bytes

)

[inline, protected]

void dirac::ByteIO::OutputCurrentByte

(

)

[inline, protected]

void dirac::ByteIO::OutputFixedLengthUint	(	const unsigned int &	value,
		const int &	length
	)			[inline, protected]

Parameters:

	value	Integer to be output
	length	number of bytes in val to output

void dirac::ByteIO::OutputVarLengthInt

(

const int

val

)

[protected]

Parameters:

val

Integer to be output

void dirac::ByteIO::OutputVarLengthUint

(

const unsigned int &

value

)

Parameters:

value

Integer to be output

void dirac::ByteIO::RemoveRedundantBytes

(

const int

count

)

[protected]

Parameters:

count

Number of bytes to be removed from beginning of stream

void dirac::ByteIO::SeekGet	(	const int	offset,
		std::ios_base::seekdir	dir
	)			[inline, protected]

void dirac::ByteIO::SetBit	(	unsigned char &	c,
		int	pos
	)			const [inline, protected]

void dirac::ByteIO::SetBits	(	unsigned char &	c,
		unsigned char	bits
	)			const [inline, protected]

void dirac::ByteIO::SetByteParams

(

const ByteIO &

byte_io

)

Parameters:

byte_io

Byte source/destination

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Friends And Related Function Documentation

friend class ArithCodecBase [friend]

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Member Data Documentation

unsigned char dirac::ByteIO::m_current_byte [private]

int dirac::ByteIO::m_current_pos [private]

bool dirac::ByteIO::m_new_stream [private]

int dirac::ByteIO::m_num_bytes [private]

std::stringstream* dirac::ByteIO::mp_stream [protected]

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

• byteio.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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