直接找ONCHANGE就可以了

CODE

// ImageReadingDoc.cpp : implementation of the CImageReadingDoc class
//

#include "stdafx.h"
#include "ImageReading.h"

#include "ImageReadingDoc.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CImageReadingDoc

IMPLEMENT_DYNCREATE(CImageReadingDoc, CDocument)

BEGIN_MESSAGE_MAP(CImageReadingDoc, CDocument)
	//{{AFX_MSG_MAP(CImageReadingDoc)
	ON_COMMAND(IDC_OPENIMAGE, OnOpenimage)
	ON_COMMAND(IDC_COLOR_TO_GRAY, OnColorToGray)
	ON_COMMAND(ID_SUB, OnSub)
	ON_COMMAND(ID_OPENIMAGE2, OnOpenimage2)
	ON_COMMAND(ID_CHANGE, OnChange)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CImageReadingDoc construction/destruction

CImageReadingDoc::CImageReadingDoc()
{
	Image = NULL;
	Image2 = NULL;
	Image3 = NULL;
}

CImageReadingDoc::~CImageReadingDoc()
{
	if(Image)
	{
		delete Image;
		Image = NULL;
	}
	if(Image2)
	{
		delete Image2;
		Image2 = NULL;
	}
	if(Image3)
	{
		delete Image3;
		Image3 = NULL;
	}
}

BOOL CImageReadingDoc::OnNewDocument()
{
	if (!CDocument::OnNewDocument())
		return FALSE;

	// TODO: add reinitialization code here
	// (SDI documents will reuse this document)

	return TRUE;
}

/////////////////////////////////////////////////////////////////////////////
// CImageReadingDoc diagnostics

#ifdef _DEBUG
void CImageReadingDoc::AssertValid() const
{
	CDocument::AssertValid();
}

void CImageReadingDoc::Dump(CDumpContext& dc) const
{
	CDocument::Dump(dc);
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CImageReadingDoc commands

static char BASED_CODE szFilter[] =
	"Support Image Files (*.bmp *.jpg *.gif *.ico)|*.bmp;*.jpg;*.gif;*.ico|BMP Files (*.bmp)|*.bmp|\
	JPEG Files (*.jpg)|*.jpg|GIF Files (*.gif)|*.gif|ICON Files (*.ico)|*.ico||";

void CImageReadingDoc::OnOpenimage()		// 開啟圖檔的主要程式
{
	// 呼叫MFC內建開啟檔案的DIALOG執行，相關資訊參考MSDN
	CFileDialog filedlg(TRUE, NULL, NULL, OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, szFilter);

	// 檢查是否按下OK按鈕，否則跳出
	if(filedlg.DoModal() != IDOK)
		return;

	// 呼叫CxImage宣告一個記憶體指標以提供相關影像解碼動作
	if(Image)
		delete Image;
	Image = new CxImage();

	CString Temp;
	Image->Load(filedlg.GetPathName());


	/*																		*\
		經過上述動作，o_ImageUL內以存放解碼後的影像資料，會用到的有
		o_ImageUL->GetWidth()		=> 獲得影像寬度
		o_ImageUL->GetHeight()		=> 獲得影像高度
		o_ImageUL->GetBits()		=> 主要影像資料	以BYTE儲存);//利用物件本身所提供之成員函數取得一個像素的 R,G,B(指標用法)
		o_ImageUL->GetDIB()			=> 影像HEADER，FOR 秀圖的時候會需要
		o_ImageUL->GetEffWidth()	=> 影像單一一列的總長度(四的倍數) EffW約為width*3  因為ㄧ個RGB3個BYTE
		o_ImageUL->GetBpp()			=> 影像位元數(1,4,8,24)  bpp = bit per pixel   


		其中 o_ImageUL->GetBits() 內的編碼方式以 BYTE 為單位
		以 B G R 三組代表影像的單一點
	\*																		*/

	// 秀圖方法：
	// 呼叫MFC內建FUNC. Refresh All Views
	UpdateAllViews(FALSE);
}

void CImageReadingDoc::OnColorToGray() 
{
	// 檢查是否以讀取影像進入記憶體，若無則跳出
	if(!Image)	return;

	// 檢查是否是24BITS(彩色)，若不是則跳出
	if(Image->GetBpp() != 24)	return;

	// 指標直接指向影像資料的記憶體位置
	BYTE	*p_Image = Image->GetBits();

	int i, j, k,
		BPP = Image->GetBpp() / 8;
	for(i=0; i < Image->GetHeight(); i++, p_Image+=Image->GetEffWidth())
		for(j=0, k=0; j < Image->GetWidth(); j++, k+=BPP){
			p_Image[k] = p_Image[k + 1] = p_Image[k + 2] = (p_Image[k] + p_Image[k + 1] + p_Image[k + 2]) / 3;

		if(p_Image[k] >=128){
				p_Image[k] = p_Image[k + 1] = p_Image[k + 2] =255;
		}
		else
		{
			p_Image[k] = p_Image[k + 1] = p_Image[k + 2] =0;
		}
		}
	// 呼叫MFC內建FUNC. Refresh All Views
	UpdateAllViews(FALSE);
}


void CImageReadingDoc::OnOpenimage2() 
{

	// 呼叫MFC內建開啟檔案的DIALOG執行，相關資訊參考MSDN
	CFileDialog filedlg(TRUE, NULL, NULL, OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, szFilter);

	// 檢查是否按下OK按鈕，否則跳出
	if(filedlg.DoModal() != IDOK)
		return;

	// 呼叫CxImage宣告一個記憶體指標以提供相關影像解碼動作
	if(Image2)
		delete Image2;
	Image2 = new CxImage();

	CString Temp;
	Image2->Load(filedlg.GetPathName());
	
	UpdateAllViews(FALSE);
}



void CImageReadingDoc::OnSub() 
{
	// TODO: Add your command handler code here
	
}

void CImageReadingDoc::OnChange() 
{
	/*
	int BPP ;

	if(!Image)
		return;

	BYTE *Buffer = new BYTE[Image->GetHeight() * Image->GetEffWidth()];

	BPP = Image->GetBpp()/8;
	
	BYTE *p_Image = Image->GetBits();
	BYTE *p_Buffer = Buffer;

	int i , j , k , l;

	for(i=0; i<Image->GetHeight(); i++, p_Image+=Image->GetEffWidth(), p_Buffer+=Image->GetEffWidth())
		for(j=0, k=0, l=(Image->GetWidth() - 1) * BPP; j < Image->GetWidth(); j++, k+=BPP, l-=BPP)

		{
			p_Buffer[l    ] = p_Image[k    ];
			p_Buffer[l + 1] = p_Image[k + 1];
			p_Buffer[l + 2] = p_Image[k + 2];
		}
		
	memcpy(Image->GetBits(), Buffer, sizeof(BYTE) * Image->GetHeight() * Image->GetEffWidth());
	delete [] Buffer;
	Buffer = NULL;

	UpdateAllViews(FALSE);

  */

/*p_image[k]=藍色
p_image[k+1]=綠色
p_image[k+2]=紅色*/

	if(!Image)
		return;
	int BPP,k;

	BYTE *p_Image = Image->GetBits();
	BPP = Image->GetBpp();
	BPP/=8;
	

	BYTE gray[1000][1000];
	

	int i,j,a;

	for(i=0;i<Image->GetHeight();i++, p_Image=p_Image+Image->GetEffWidth())
		for(j=0,k=0;j<Image->GetWidth();j++,k+=BPP)
		{

			p_Image[k]=0.299*p_Image[k+2]+0.587*p_Image[k+1]+0.114*p_Image[k];
			p_Image[k+2] = p_Image[k+1] = p_Image[k];

			gray[i][j]=p_Image[k];

			//將彩色的圖轉為灰階,並把資料存入gray陣列中


		/*	if(p_Image[k] >= 128){

				p_Image[k] = p_Image[k+1] = p_Image[k+2]= 255;
				//p_Image[k] = 255;
				
				
			}
			else{
				p_Image[k] = p_Image[k+1] = p_Image[k+2]=  0;
			}*/
		}
		
	
//以下是演算法QQ

	/*for(i=1;i<Image->GetHeight();i++, p_Image=p_Image+Image->GetEffWidth())
		for(j=1,k=0;j<Image->GetWidth();j++,k+=BPP)
		{
			
				BYTE a = gray[i-1][j-1];
				BYTE b = gray[i][j-1];
				BYTE c = gray[i+1][j-1];
				BYTE d = gray[i-1][j];
				BYTE e = gray[i+1][j];
				BYTE f = gray[i-1][j+1];
				BYTE g = gray[i][j+1];
				BYTE h = gray[i+1][j+1];

				BYTE hor = (a+d+f) - (c+e+h);
				BYTE vert = (a+b+c) - (f+g+h);
				if(hor<0)
					hor=-(hor);
				if(vert<0)
					vert=-(vert);
				BYTE gxy = hor + vert;

				if (gxy>128)
				{
					p_Image[k] = 255;
					p_Image[k+1] = 255;
					p_Image[k+2]= 255;
				}
				else
				{
					p_Image[k] = 0;
					p_Image[k+1] = 0;
					p_Image[k+2]= 0;
				}
		}*/
	UpdateAllViews(FALSE);
}

/*
int BPP ;

	if(!Image)
		return;

	BYTE *Buffer = new BYTE[Image->GetHeight() * Image->GetEffWidth()];

	BPP = Image->GetBpp()/8;
	
	BYTE *p_Image = Image->GetBits();
	BYTE *p_Buffer = Buffer;

	int i , j , k , l;

	for(i=0; i<Image->GetHeight(); i++, p_Image+=Image->GetEffWidth(), p_Buffer+=Image->GetEffWidth())
		for(j=0, k=0, l=(Image->GetWidth() - 1) * BPP; j < Image->GetWidth(); j++, k+=BPP, l-=BPP)

		{
			p_Buffer[l    ] = p_Image[k    ];
			p_Buffer[l + 1] = p_Image[k + 1];
			p_Buffer[l + 2] = p_Image[k + 2];
		}
		
	memcpy(Image->GetBits(), Buffer, sizeof(BYTE) * Image->GetHeight() * Image->GetEffWidth());
	delete [] Buffer;
	Buffer = NULL;

	UpdateAllViews(FALSE);
*/



/*
	BYTE	*p_Image = Image->GetBits();
	BYTE	*temp_Image = Image->GetBits();
	int i, j, k;
	int a,b;
	a = Image->GetEffWidth();	
	b = a/2;
	for(i=0; i < Image->GetHeight(); i++, p_Image+=Image->GetEffWidth(),temp_Image+=Image->GetEffWidth())
	{
		for(j=0,k=0; j < b,k < b; j+=3,k-=3)
		{
			temp_Image[j] = p_Image[k];
			temp_Image[j+1] = p_Image[k+1];
			temp_Image[j+2] = p_Image[k+2];
		}
	}
  UpdateAllViews(FALSE);
}

	
	/*	temp_Image[a-j-1] = p_Image[j];
				p_Image[j] = p_Image[a-j-1] ;
				p_Image[a-j-1] = temp_Image[a-j-1];*/

gistfile2.c