/work/vvdec/source/Lib/DecoderLib/VLCReader.h

Source
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/** \file     VLCReader.h
 *  \brief    Reader for high level syntax
 */

#pragma once

#include "CommonLib/BitStream.h"

#if ENABLE_TRACING

#define READ_CODE( length, code, name)    xReadCode ( length, code, name )
#define READ_UVLC(         code, name)    xReadUvlc (         code, name )
#define READ_SVLC(         code, name)    xReadSvlc (         code, name )
#define READ_FLAG(         code, name)    xReadFlag (         code, name )
#define READ_SCODE(length, code, name)    xReadSCode( length, code, name )

#else

#define READ_CODE( length, code, name)    xReadCode  ( length, code )
#define READ_UVLC(         code, name)    xReadUvlc  (         code )
#define READ_SVLC(         code, name)    xReadSvlc  (         code )
#define READ_FLAG(         code, name)    xReadFlag  (         code )
#define READ_SCODE(length, code, name)    xReadSCode ( length, code )

#endif

#if ENABLE_TRACING
#  define X_READ_FLAG(  name )                             const bool     name = xReadFlag ( #name )
#  define X_READ_FLAG_idx( name, idx )                     const bool     name = xReadFlag ( #name idx )

#  define  X_READ_UVLC_NO_RANGE(  name         )           const uint32_t name = xReadUvlc (         #name )
#  define  X_READ_SVLC_NO_RANGE(  name         )           const int32_t  name = xReadSvlc (         #name )
#  define  X_READ_CODE_NO_RANGE(  name, length )           const uint32_t name = xReadCode ( length, #name )
#  define  X_READ_SCODE_NO_RANGE( name, length )           const int32_t  name = xReadSCode( length, #name )

#  define  X_READ_UVLC_NO_RANGE_idx(  name, idx         )  const uint32_t name = xReadUvlc (         #name idx )
#  define  X_READ_SVLC_NO_RANGE_idx(  name, idx         )  const int32_t  name = xReadSvlc (         #name idx )
#  define  X_READ_CODE_NO_RANGE_idx(  name, idx, length )  const uint32_t name = xReadCode ( length, #name idx )
#  define  X_READ_SCODE_NO_RANGE_idx( name, idx, length )  const int32_t  name = xReadSCode( length, #name idx )

#else

#  define X_READ_FLAG( name )                              const bool     name = xReadFlag ()
#  define X_READ_FLAG_idx( name, idx )                     const bool     name = xReadFlag ()

#  define X_READ_UVLC_NO_RANGE(  name         )            const uint32_t name = xReadUvlc (        )
#  define X_READ_SVLC_NO_RANGE(  name         )            const int32_t  name = xReadSvlc (        )
#  define X_READ_CODE_NO_RANGE(  name, length )            const uint32_t name = xReadCode ( length )
#  define X_READ_SCODE_NO_RANGE( name, length )            const int32_t  name = xReadSCode( length )

#  define X_READ_UVLC_NO_RANGE_idx(  name, idx         )   const uint32_t name = xReadUvlc (        )
#  define X_READ_SVLC_NO_RANGE_idx(  name, idx         )   const int32_t  name = xReadSvlc (        )
#  define X_READ_CODE_NO_RANGE_idx(  name, idx, length )   const uint32_t name = xReadCode ( length )
#  define X_READ_SCODE_NO_RANGE_idx( name, idx, length )   const int32_t  name = xReadSCode( length )

#endif


#define X_READ_FLAG_CHECK( name,          chk_cond, chk_msg ) const bool name = [&]{ X_READ_FLAG     ( name      ); CHECK_READ( chk_cond, chk_msg, name ); return name; }()
#define X_READ_FLAG_CHECK_idx( name, idx, chk_cond, chk_msg ) const bool name = [&]{ X_READ_FLAG_idx ( name, idx ); CHECK_READ( chk_cond, chk_msg, name ); return name; }()

// use immediately invoked lambdas, to ensure we get a warning, when the result is unused
#define X_READ_UVLC( name,         min, max )                 const uint32_t name = [&]{ X_READ_UVLC_NO_RANGE( name         ); CHECK_READ_RANGE( name, min, max, #name ); return name; }()
#define X_READ_SVLC( name,         min, max )                 const int32_t  name = [&]{ X_READ_SVLC_NO_RANGE( name         ); CHECK_READ_RANGE( name, min, max, #name ); return name; }()
#define X_READ_CODE( name, length, min, max )                 const uint32_t name = [&]{ X_READ_CODE_NO_RANGE( name, length ); CHECK_READ_RANGE( name, min, max, #name ); return name; }()
#define X_READ_SCODE(name, length, min, max )                 const int32_t  name = [&]{ X_READ_SCODE_NO_RANGE(name, length ); CHECK_READ_RANGE( name, min, max, #name ); return name; }()

#define X_READ_UVLC_idx( name, idx,         min, max )        const uint32_t name = [&]{ X_READ_UVLC_NO_RANGE_idx( name, idx         ); CHECK_READ_RANGE( name, min, max, (#name idx) ); return name; }()
#define X_READ_SVLC_idx( name, idx,         min, max )        const int32_t  name = [&]{ X_READ_SVLC_NO_RANGE_idx( name, idx         ); CHECK_READ_RANGE( name, min, max, (#name idx) ); return name; }()
#define X_READ_CODE_idx( name, idx, length, min, max )        const uint32_t name = [&]{ X_READ_CODE_NO_RANGE_idx( name, idx, length ); CHECK_READ_RANGE( name, min, max, (#name idx) ); return name; }()
#define X_READ_SCODE_idx(name, idx, length, min, max )        const int32_t  name = [&]{ X_READ_SCODE_NO_RANGE_idx(name, idx, length ); CHECK_READ_RANGE( name, min, max, (#name idx) ); return name; }()


namespace vvdec
{

// ====================================================================================================================
// Class definition
// ====================================================================================================================

class VLCReader
{
protected:
  InputBitstream* m_pcBitstream = nullptr;   // we never own this object

  VLCReader()          = default;
  virtual ~VLCReader() = default;

  // read functions taking a reference for the result
  void xReadFlag (                  uint32_t& val );
  void xReadUvlc (                  uint32_t& val );
  void xReadSvlc (                  int32_t&  val );
  void xReadCode ( uint32_t length, uint32_t& val );
  void xReadSCode( uint32_t length, int32_t&  val );

  // read functions taking a reference for the result - tracing overloads
  void xReadFlag (                  uint32_t& rValue, const char* pSymbolName );
  void xReadUvlc (                  uint32_t& rValue, const char* pSymbolName );
  void xReadSvlc (                  int32_t&  rValue, const char* pSymbolName );
  void xReadCode ( uint32_t length, uint32_t& rValue, const char* pSymbolName );
  void xReadSCode( uint32_t length, int32_t&  rValue, const char* pSymbolName );

  // read functions returning the result value
  bool     xReadFlag();
  uint32_t xReadUvlc();
  int32_t  xReadSvlc();
  uint32_t xReadCode( uint32_t length );
  int32_t  xReadSCode( uint32_t length );

  // read functions returning the result value - tracing overloads
  bool     xReadFlag (                  const char* pSymbolName );
  uint32_t xReadUvlc (                  const char* pSymbolName );
  int32_t  xReadSvlc (                  const char* pSymbolName );
  uint32_t xReadCode ( uint32_t length, const char* pSymbolName );
  int32_t  xReadSCode( uint32_t length, const char* pSymbolName );

public:
  void            setBitstream( InputBitstream* p ) { m_pcBitstream = p; }
  InputBitstream* getBitstream() { return m_pcBitstream; }

protected:
  void xReadRbspTrailingBits();
  bool isByteAligned() { return ( m_pcBitstream->getNumBitsUntilByteAligned() == 0 ); }
};

}   // namespace vvdec

Coverage Report

Created: 2026-10-28 06:18