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// BitlEncoder.h -- the Least Significant Bit of byte is First
#ifndef __BITL_ENCODER_H
#define __BITL_ENCODER_H
#include "../Common/OutBuffer.h"
class CBitlEncoder
{
COutBuffer m_Stream;
unsigned m_BitPos;
Byte m_CurByte;
public:
bool Create(UInt32 bufferSize) { return m_Stream.Create(bufferSize); }
void SetStream(ISequentialOutStream *outStream) { m_Stream.SetStream(outStream); }
void ReleaseStream() { m_Stream.ReleaseStream(); }
UInt32 GetBitPosition() const { return (8 - m_BitPos); }
UInt64 GetProcessedSize() const { return m_Stream.GetProcessedSize() + (8 - m_BitPos + 7) /8; }
void Init()
{
m_Stream.Init();
m_BitPos = 8;
m_CurByte = 0;
}
HRESULT Flush()
{
FlushByte();
return m_Stream.Flush();
}
void FlushByte()
{
if (m_BitPos < 8)
m_Stream.WriteByte(m_CurByte);
m_BitPos = 8;
m_CurByte = 0;
}
void WriteBits(UInt32 value, unsigned numBits)
{
while (numBits > 0)
{
if (numBits < m_BitPos)
{
m_CurByte |= (value & ((1 << numBits) - 1)) << (8 - m_BitPos);
m_BitPos -= numBits;
return;
}
numBits -= m_BitPos;
m_Stream.WriteByte((Byte)(m_CurByte | (value << (8 - m_BitPos))));
value >>= m_BitPos;
m_BitPos = 8;
m_CurByte = 0;
}
}
void WriteByte(Byte b) { m_Stream.WriteByte(b);}
};
#endif
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