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diff --git a/src/ml/dlib/dlib/compress_stream/compress_stream_kernel_3.h b/src/ml/dlib/dlib/compress_stream/compress_stream_kernel_3.h
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+// Copyright (C) 2005 Davis E. King (davis@dlib.net)
+// License: Boost Software License See LICENSE.txt for the full license.
+#ifndef DLIB_COMPRESS_STREAM_KERNEl_3_
+#define DLIB_COMPRESS_STREAM_KERNEl_3_
+
+#include "../algs.h"
+#include "compress_stream_kernel_abstract.h"
+#include "../assert.h"
+
+namespace dlib
+{
+
+ template <
+ typename lzp_buf,
+ typename crc32,
+ unsigned long buffer_size
+ >
+ class compress_stream_kernel_3
+ {
+ /*!
+ REQUIREMENTS ON lzp_buf
+ is an implementation of lzp_buffer/lzp_buffer_kernel_abstract.h
+
+ REQUIREMENTS ON buffer_size
+ 10 < buffer_size < 32
+
+ REQUIREMENTS ON crc32
+ is an implementation of crc32/crc32_kernel_abstract.h
+
+
+ INITIAL VALUE
+ this object has no state
+
+ CONVENTION
+ this object has no state
+
+
+ This implementation uses the lzp_buffer and writes out matches
+ in a byte aligned format.
+
+ !*/
+
+
+ public:
+
+ class decompression_error : public dlib::error
+ {
+ public:
+ decompression_error(
+ const char* i
+ ) :
+ dlib::error(std::string(i))
+ {}
+
+ decompression_error(
+ const std::string& i
+ ) :
+ dlib::error(i)
+ {}
+ };
+
+
+ compress_stream_kernel_3 (
+ )
+ {
+ COMPILE_TIME_ASSERT(10 < buffer_size && buffer_size < 32);
+ }
+
+ ~compress_stream_kernel_3 (
+ )
+ {}
+
+ void compress (
+ std::istream& in,
+ std::ostream& out
+ ) const;
+
+ void decompress (
+ std::istream& in,
+ std::ostream& out
+ ) const;
+
+
+
+ private:
+
+ inline void write (
+ unsigned char symbol
+ ) const
+ {
+ if (out->sputn(reinterpret_cast<char*>(&symbol),1)==0)
+ throw std::ios_base::failure("error writing to output stream in compress_stream_kernel_3");
+ }
+
+ inline void decode (
+ unsigned char& symbol,
+ unsigned char& flag
+ ) const
+ {
+ if (count == 0)
+ {
+ if (((size_t)in->sgetn(reinterpret_cast<char*>(buffer),sizeof(buffer)))!=sizeof(buffer))
+ throw decompression_error("Error detected in compressed data stream.");
+ count = 8;
+ }
+ --count;
+ symbol = buffer[8-count];
+ flag = buffer[0] >> 7;
+ buffer[0] <<= 1;
+ }
+
+ inline void encode (
+ unsigned char symbol,
+ unsigned char flag
+ ) const
+ /*!
+ requires
+ - 0 <= flag <= 1
+ ensures
+ - writes symbol with the given one bit flag
+ !*/
+ {
+ // add this symbol and flag to the buffer
+ ++count;
+ buffer[0] <<= 1;
+ buffer[count] = symbol;
+ buffer[0] |= flag;
+
+ if (count == 8)
+ {
+ if (((size_t)out->sputn(reinterpret_cast<char*>(buffer),sizeof(buffer)))!=sizeof(buffer))
+ throw std::ios_base::failure("error writing to output stream in compress_stream_kernel_3");
+ count = 0;
+ buffer[0] = 0;
+ }
+ }
+
+ void clear (
+ ) const
+ /*!
+ ensures
+ - resets the buffers
+ !*/
+ {
+ count = 0;
+ }
+
+ void flush (
+ ) const
+ /*!
+ ensures
+ - flushes any data in the buffers to out
+ !*/
+ {
+ if (count != 0)
+ {
+ buffer[0] <<= (8-count);
+ if (((size_t)out->sputn(reinterpret_cast<char*>(buffer),sizeof(buffer)))!=sizeof(buffer))
+ throw std::ios_base::failure("error writing to output stream in compress_stream_kernel_3");
+ }
+ }
+
+ mutable unsigned int count;
+ // count tells us how many bytes are buffered in buffer and how many flag
+ // bit are currently in buffer[0]
+ mutable unsigned char buffer[9];
+ // buffer[0] holds the flag bits to be writen.
+ // the rest of the buffer holds the bytes to be writen.
+
+ mutable std::streambuf* in;
+ mutable std::streambuf* out;
+
+ // restricted functions
+ compress_stream_kernel_3(compress_stream_kernel_3<lzp_buf,crc32,buffer_size>&); // copy constructor
+ compress_stream_kernel_3<lzp_buf,crc32,buffer_size>& operator=(compress_stream_kernel_3<lzp_buf,crc32,buffer_size>&); // assignment operator
+
+ };
+
+// ----------------------------------------------------------------------------------------
+// ----------------------------------------------------------------------------------------
+ // member function definitions
+// ----------------------------------------------------------------------------------------
+// ----------------------------------------------------------------------------------------
+
+ template <
+ typename lzp_buf,
+ typename crc32,
+ unsigned long buffer_size
+ >
+ void compress_stream_kernel_3<lzp_buf,crc32,buffer_size>::
+ compress (
+ std::istream& in_,
+ std::ostream& out_
+ ) const
+ {
+ in = in_.rdbuf();
+ out = out_.rdbuf();
+ clear();
+
+ crc32 crc;
+
+ lzp_buf buffer(buffer_size);
+
+ std::streambuf::int_type temp = in->sbumpc();
+ unsigned long index;
+ unsigned char symbol;
+ unsigned char length;
+
+ while (temp != EOF)
+ {
+ symbol = static_cast<unsigned char>(temp);
+ if (buffer.predict_match(index))
+ {
+ if (buffer[index] == symbol)
+ {
+ // this is a match so we must find out how long it is
+ length = 1;
+
+ buffer.add(symbol);
+ crc.add(symbol);
+
+ temp = in->sbumpc();
+ while (length < 255)
+ {
+ if (temp == EOF)
+ {
+ break;
+ }
+ else if (static_cast<unsigned long>(length) >= index)
+ {
+ break;
+ }
+ else if (static_cast<unsigned char>(temp) == buffer[index])
+ {
+ ++length;
+ buffer.add(static_cast<unsigned char>(temp));
+ crc.add(static_cast<unsigned char>(temp));
+ temp = in->sbumpc();
+ }
+ else
+ {
+ break;
+ }
+ }
+
+ encode(length,1);
+ }
+ else
+ {
+ // this is also not a match
+ encode(symbol,0);
+ buffer.add(symbol);
+ crc.add(symbol);
+
+ // get the next symbol
+ temp = in->sbumpc();
+ }
+ }
+ else
+ {
+ // there wasn't a match so just write this symbol
+ encode(symbol,0);
+ buffer.add(symbol);
+ crc.add(symbol);
+
+ // get the next symbol
+ temp = in->sbumpc();
+ }
+ }
+
+ // use a match of zero length to indicate EOF
+ encode(0,1);
+
+ // now write the checksum
+ unsigned long checksum = crc.get_checksum();
+ unsigned char byte1 = static_cast<unsigned char>((checksum>>24)&0xFF);
+ unsigned char byte2 = static_cast<unsigned char>((checksum>>16)&0xFF);
+ unsigned char byte3 = static_cast<unsigned char>((checksum>>8)&0xFF);
+ unsigned char byte4 = static_cast<unsigned char>((checksum)&0xFF);
+
+ encode(byte1,0);
+ encode(byte2,0);
+ encode(byte3,0);
+ encode(byte4,0);
+
+ flush();
+ }
+
+// ----------------------------------------------------------------------------------------
+
+ template <
+ typename lzp_buf,
+ typename crc32,
+ unsigned long buffer_size
+ >
+ void compress_stream_kernel_3<lzp_buf,crc32,buffer_size>::
+ decompress (
+ std::istream& in_,
+ std::ostream& out_
+ ) const
+ {
+ in = in_.rdbuf();
+ out = out_.rdbuf();
+ clear();
+
+ crc32 crc;
+
+ lzp_buf buffer(buffer_size);
+
+
+ unsigned long index = 0;
+ unsigned char symbol;
+ unsigned char length;
+ unsigned char flag;
+
+ decode(symbol,flag);
+ while (flag == 0 || symbol != 0)
+ {
+ buffer.predict_match(index);
+
+ if (flag == 1)
+ {
+ length = symbol;
+ do
+ {
+ --length;
+ symbol = buffer[index];
+ write(symbol);
+ buffer.add(symbol);
+ crc.add(symbol);
+ } while (length != 0);
+ }
+ else
+ {
+ // this is just a literal
+ write(symbol);
+ buffer.add(symbol);
+ crc.add(symbol);
+ }
+ decode(symbol,flag);
+ }
+
+
+ // now get the checksum and make sure it matches
+ unsigned char byte1;
+ unsigned char byte2;
+ unsigned char byte3;
+ unsigned char byte4;
+
+ decode(byte1,flag);
+ if (flag != 0)
+ throw decompression_error("Error detected in compressed data stream.");
+ decode(byte2,flag);
+ if (flag != 0)
+ throw decompression_error("Error detected in compressed data stream.");
+ decode(byte3,flag);
+ if (flag != 0)
+ throw decompression_error("Error detected in compressed data stream.");
+ decode(byte4,flag);
+ if (flag != 0)
+ throw decompression_error("Error detected in compressed data stream.");
+
+ unsigned long checksum = byte1;
+ checksum <<= 8;
+ checksum |= byte2;
+ checksum <<= 8;
+ checksum |= byte3;
+ checksum <<= 8;
+ checksum |= byte4;
+
+ if (checksum != crc.get_checksum())
+ throw decompression_error("Error detected in compressed data stream.");
+
+ }
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_COMPRESS_STREAM_KERNEl_3_
+
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