//------------------------------------------------------------
//?arith-n.cpp?-?order-n?arithmetic?coding?module

#include?
#include?
#include?
#include?“errhand.h“
#include?“bitio.h“

//?low_count?和?high_count?唯一地定義了在?0?到?1?范圍中符號的所在位置
//?scale?指?0?到?1?范圍內的總量程，即有多少字符要記數
typedef?struct
{
	unsigned?short?int?low_count;
	unsigned?short?int?high_count;
	unsigned?short?int?scale;
}SYMBOL;


void?build_model（FILE?*inputFILE?*output）;
void?scale_counts（unsigned?long?counts[]unsigned?char?scaled_counts[]）;
void?build_totals（unsigned?char?scaled_counts[]）;
void?count_bytes（FILE?*inputunsigned?long?counts[]）;
void?output_counts（FILE?*outputunsigned?char?scaled_counts[]）;
void?input_counts（FILE?*stream）;
void?convert_int_to_symbol（int?symbolSYMBOL?*s）;
void?get_symbol_scale（SYMBOL?*s）;
int?convert_symbol_to_int（int?countSYMBOL?*s）;

void?initialize_arithmetic_encoder（void）;
void?encode_symbol（BIT_FILE?*streamSYMBOL?*s）;
void?flush_arithmetic_encoder（BIT_FILE?*stream）;
short?int?get_current_count（SYMBOL?*s）;
void?initialize_arithmetic_decoder（BIT_FILE?*stream）;
void?remove_symbol_from_stream（BIT_FILE?*streamSYMBOL?*s）;


#define?END_OF_STREAM?256
short?int?totals[258];


char*?CompressionName	=?“Adaptive?order?n?moder?with?arithmetic?coding“;
char*?Usage				=?“in-file?out-file?[-o?order]\n\n“;


void?CompressFile（?FILE*?input?BIT_FILE*?output?int?argc?char?*?argv[]?）
{
??int?c;
??SYMBOL?s;


??build_model（inputoutput->file）;
??initialize_arithmetic_encoder（）;


??while（（c=getc（input））!=EOF）{
?????convert_int_to_symbol（c&s）;
	?encode_symbol（output&s）;
	?}
	?convert_int_to_symbol（END_OF_STREAM&s）;
	?encode_symbol（output&s）;
	?flush_arithmetic_encoder（output）;
	?OutputBits（output0L16）;
	?while（argc-->0）{
	?printf（“Unused?argument:%s\n“*argv）;
	?argv++;
	?}
	?}



void?ExpandFile（?BIT_FILE*?input?FILE*?output?int?argc?char*?argv[]）
{
	SYMBOL?s;
	int?c;
	int?count;

????input_counts（input->file）;
	initialize_arithmetic_decoder（input）;
	for?（;;）
	{	
			get_symbol_scale（?&s?）;
			count?=?get_current_count（?&s?）;
			c?=?convert_symbol_to_int（?count?&s?）;
			if（c==END_OF_STREAM）?
				break;
			remove_symbol_from_stream（?input?&s?）;
		putc（（char）coutput）;
	}
		while（argc-->0）
	{
		printf（“Unused?argument:%s\n“*argv）;
		argv++;
	}
}

void?build_model（FILE?*inputFILE?*output）

{
	?unsigned?long?counts[256];
	?unsigned?char?scaled_counts[256];


	count_bytes（inputcounts）;
	scale_counts（countsscaled_counts）;
	output_counts（outputscaled_counts）;
	build_totals（scaled_counts）;
}


?#ifndef?SEEK_SET
?#define?SEEK_SET?0
?#endif



?void?count_bytes（FILE?*inputunsigned?long?counts[]）
?
?
?{
????long?input_marker;
	int?i;
	int?c;

?????for（i=0;i<256;i++）
		?counts[i]=0;
	?input_marker=ftell（input）;
	?while（（c=getc（input））!=EOF）
	????counts[c]++;
	fseek（inputinput_markerSEEK_SET）;
?}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????541??2009-06-08?18:49??encoding1\encoding1.dsw

?????文件??????41984??2009-06-08?18:55??encoding1\encoding1.ncb

?????文件????????267??2004-11-14?12:02??encoding1\errhand.cpp

?????文件????????142??2004-11-14?12:03??encoding1\errhand.h

?????文件????????311??2004-11-14?12:03??encoding1\main.h

?????文件???????2066??2004-11-14?12:04??encoding1\main-c.cpp

?????文件???????8915??2009-06-02?15:43??encoding1\arith.cpp

?????文件???????3389??2004-11-14?12:02??encoding1\bitio.cpp

?????文件????????815??2004-11-14?12:02??encoding1\bitio.h

?????文件???????1342??2009-06-08?18:50??encoding1\encoding1.plg

?????文件??????49664??2009-06-08?18:55??encoding1\encoding1.opt

?????文件???????4688??2009-06-08?18:55??encoding1\encoding1.dsp

?????文件??????41984??2009-06-08?18:50??encoding1\Debug\vc60.idb

?????文件??????53248??2009-06-08?18:50??encoding1\Debug\vc60.pdb

?????文件???????7101??2009-06-08?18:50??encoding1\Debug\main-c.obj

?????文件??????19149??2009-06-08?18:50??encoding1\Debug\arith.obj

?????文件??????10373??2009-06-08?18:50??encoding1\Debug\bitio.obj

?????文件?????220808??2009-06-08?18:50??encoding1\Debug\encoding1.pch

?????文件???????2144??2009-06-08?18:50??encoding1\Debug\errhand.obj

?????文件?????199904??2009-06-08?18:50??encoding1\Debug\encoding1.ilk

?????文件?????192561??2009-06-08?18:50??encoding1\Debug\encoding1.exe

?????文件?????394240??2009-06-08?18:50??encoding1\Debug\encoding1.pdb

?????目錄??????????0??2009-06-08?19:01??encoding1\Debug

?????目錄??????????0??2009-06-08?19:01??encoding1

-----------?---------??----------?-----??----

??????????????1255636????????????????????24