//原文出處：
//http://members.easyshag.com/femaledesperation/cg01.html
//http://members.easyshag.com/femaledesperation/gillian22.html#top
//問題：沒考慮對齊！

/*?原理：
The?usual?approach?is?to?create?an?array?representing?a?histogram?of?colors?
and?color?frequencies?sort?the?array?in?order?of?descending?frequencies
and?copy?the?first?236?colors?in?the?array?to?the?palette.
To?keep?the?array?size?manageable?the?least?significant?3?or?4?bits?of?each?8-bit?color
component?are?normally?discarded.?A?popularity?palette?generally?produces?better?output?
than?a?halftone?palette?but?infrequently?appearing?colors?that?are?nonetheless?important
to?the?eye?may?be?omitted.*/?

/***************
bmpTest.cpp
****************/
#include?“Test.h“
//?計算平P方F差C的函數
int?PFC（int?color1?int?color2）
{
	int?xyz;
	x?=?（color1?&?0xf）?-?（color2?&?0xf）;
	y?=?（（color1>>4）?&?0xf）?-?（（color2>>4）?&?0xf）;
	z?=?（（color1>>8）?&?0xf）?-?（（color2>>8）?&?0xf）;
	return?（x*x?+?y*y?+?z*z）;
};
//?直接插入排序
int?Sort1（int?*src?int?*attach?int?n）
{
	int?cur?cur1;
	int?ijk=0;
	for?（i?=?1;?i?	{
		cur=?src[i];
		cur1?=?attach[i];
		for?（j?=?i?-?1;?j?>=?0;?j--）
		{
			if?（cur?>?src[j]）
			{
				src[j+1]=?src[j];
				attach[j+1]?=?attach[j];
			}
			else
			{
				break;
			}
		}
		src[j+1]=?cur;
		attach[j+1]?=?cur1;
	}
	return?0;
}
//?快速排序
int?Sort2（int?*src?int?*attach?int?n）
{
	if?（n?<=?12）?return?Sort1（src?attach?n）;
	int?low?=?1?high?=?n?-?1;
	int?tmp;
	while?（low?<=?high）
	{
		while?（src[low]?>=?src[0]）
		{
			if?（++low?>?（n?-?1））?break;
		}
		while?（src[high]?		{
			if?（--high?		}
		if?（low?>?high）?break;
//
		tmp=?src[low];
		src[low]=?src[high];
		src[high]=?tmp;
		tmp=?attach[low];
		attach[low]=?attach[high];
		attach[high]=?tmp;
		low++;
		high--;
	}
//	
	tmp=?src[low?-?1];
	src[low?-?1]=?src[0];
	src[0]=?tmp;
	tmp=?attach[low?-?1];
	attach[low?-?1]=?attach[0];
	attach[0]=?tmp;
//
	if?（low?>?1）?Sort2（src?attach?low?-?1）;
	if?（low?//
	return?0;
}
//?將?24?bit?的象素顏色數據轉換為?256?色圖的圖像數據（即索引值）
int?Transfer（WORD?*shortColor?int?BytesPerRow?int?bmWidth?int?bmHeight?BYTE?*out8Dib?RGBQUAD?*mainColor）
{//?BytesPerRow?may?not?equel?bmWidth?!
	int?usedTimes[4096]?=?{0};//12b
	int?miniColor[4096];
	int?ij;
	for?（i?=?0;?i?//
	for?（i?=?0;?i?	{
		usedTimes[shortColor[i]]?++;//?get?frequency
	}
	
	int?numberOfColors?=?0;
	for?（i?=?0;?i?	{
		if?（usedTimes[i]?>?0）?numberOfColors++;
	}
	//?對usedTimes進行排序，排序過程中minColor數組（保存了顏色值）也作與useTimes
	//?數組相似的交換
	Sort2（usedTimes?miniColor?4096）;
	//?usedTimes數組中是各顏色使用頻率，從高到低排列，顯然第numberOfColor個之后的都為0
	//?miniColor數組中是相應的顏色數據
	//?將前256個顏色數據保存到256色位圖的調色盤中
	for?（i?=?0;?i?	{
		mainColor[i].rgbBlue=?（BYTE）（（miniColor[i]>>8）<<4）;
		mainColor[i].rgbGreen=?（BYTE）（（（miniColor[i]>>4）?&?0xf）<<4）;
		mai

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

?????文件???????8086??2016-11-23?12:26??真彩24位轉256色\BMP_ReadWrite.cpp

?????文件???????3548??2011-12-07?14:44??真彩24位轉256色\BMP_ReadWrite.dsp

?????文件????????551??2011-12-05?11:52??真彩24位轉256色\BMP_ReadWrite.dsw

?????文件??????58368??2016-11-23?14:30??真彩24位轉256色\BMP_ReadWrite.ncb

?????文件?????136704??2016-11-23?14:30??真彩24位轉256色\BMP_ReadWrite.opt

?????文件???????1412??2016-11-23?12:26??真彩24位轉256色\BMP_ReadWrite.plg

?????文件????????240??2016-11-23?14:30??真彩24位轉256色\BMP_ReadWrite.positions

?????文件????1934336??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.bsc

?????文件?????176239??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.exe

?????文件?????207732??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.ilk

?????文件??????25533??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.obj

????I.A....???4494808??2016-11-23?12:02??真彩24位轉256色\Debug\BMP_ReadWrite.pch

?????文件?????500736??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.pdb

?????文件??????????0??2016-11-23?12:26??真彩24位轉256色\Debug\BMP_ReadWrite.sbr

?????文件?????132096??2016-11-23?12:26??真彩24位轉256色\Debug\vc60.idb

?????文件??????77824??2016-11-23?12:26??真彩24位轉256色\Debug\vc60.pdb

?????文件???????3630??2011-12-07?13:40??真彩24位轉256色\test.h

?????文件???????1582??2016-11-23?12:26??真彩24位轉256色\testout.bmp

?????文件??????10341??2011-12-14?11:18??真彩24位轉256色\讀寫BMP示例.txt

?????目錄??????????0??2016-11-23?12:26??真彩24位轉256色\Debug

?????目錄??????????0??2016-11-23?14:30??真彩24位轉256色

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??????????????7773766????????????????????21