dlib C++ Library - bit_stream_multi_1.h

// Copyright (C) 2003 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#ifndef DLIB_BIT_STREAM_MULTi_1_
#define DLIB_BIT_STREAM_MULTi_1_
#include "bit_stream_multi_abstract.h"
namespace dlib
{
 template <
 typename bit_stream_base
 >
 class bit_stream_multi_1 : public bit_stream_base
 {
 public:
 void multi_write (
 unsigned long data,
 int num_to_write
 );
 int multi_read (
 unsigned long& data,
 int num_to_read
 );
 };
 template <
 typename bit_stream_base
 >
 inline void swap (
 bit_stream_multi_1<bit_stream_base>& a, 
 bit_stream_multi_1<bit_stream_base>& b 
 ) { a.swap(b); }
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
 // member function definitions
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
 template <
 typename bit_stream_base
 >
 void bit_stream_multi_1<bit_stream_base>:: 
 multi_write (
 unsigned long data,
 int num_to_write
 )
 {
 // move the first bit into the most significant position
 data <<= 32 - num_to_write;
 for (int i = 0; i < num_to_write; ++i)
 {
 // write the first bit from data
 this->write(static_cast<char>(data >> 31));
 // shift the next bit into position
 data <<= 1;
 }
 }
// ----------------------------------------------------------------------------------------
 template <
 typename bit_stream_base
 >
 int bit_stream_multi_1<bit_stream_base>:: 
 multi_read (
 unsigned long& data,
 int num_to_read
 )
 {
 int bit, i;
 data = 0;
 for (i = 0; i < num_to_read; ++i)
 {
 // get a bit
 if (this->read(bit) == false)
 break;
 // shift data to make room for this new bit
 data <<= 1;
 // put bit into the least significant position in data
 data += static_cast<unsigned long>(bit);
 }
 return i;
 }
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_BIT_STREAM_MULTi_1_