各位大大~~我有一個問題

我先照了一張背景圖後~再用webcam照同一地方並加入物體

我想將我想將兩圖做相減~~並二質化~~但是我做出來都有錯
請各位大大幫我看看吧!!

void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
//影像做灰階
int k=0, B1=0, G1=0, R1=0, gray=0;
TCanvas *csBuf1=new TCanvas;
HDC hDC1=GetDC(Form1->Panel1->Handle); // 取得視窗的包含工作區的畫面
csBuf1->Handle=hDC1;
Graphics::TBitmap *photo1 = new Graphics::TBitmap(); // 儲存欲處理的影像資料指標
photo1->Width=320;
photo1->Height=240;
photo1->PixelFormat = pf24bit;
photo1->Canvas->CopyRect(Rect(0,0,320,240),csBuf1,Rect(0,0,320,240));
Application->ProcessMessages();
for(int y = 0 ; y < 240; y )
{
Byte *ptr1=(Byte*)photo1->ScanLine[y];
for(int x = 0 ; x < 320 ; x )
{
k=3*x;
B1 = ptr1[k ];
G1 = ptr1[k 1];
R1 = ptr1[k 2];
gray=(B1 R1 G1)/3;
ptr1[k ]=gray;
ptr1[k 1]=gray;
ptr1[k 2]=gray;

}
}

Image1->Canvas->Draw(0,0,photo1);
delete photo1;
delete csBuf1;

}
//---------------------------------------------------------------------------

void __fastcall TForm1::ConnectClick(TObject *Sender)
{
hWndC_CCD1=capCreateCaptureWindow("Capture Window1",WS_CHILD | WS_VISIBLE,0,0,320,240,Panel1->Handle,0);
capDriverConnect(hWndC_CCD1,0); //與驅動程式連結
capPreviewRate(hWndC_CCD1,10); //每秒影像變化張數
CAPDRIVERCAPS aCAPDRIVERCAPS;
aCAPDRIVERCAPS.wDeviceIndex=0;
capDriverConnect(hWndC_CCD1,aCAPDRIVERCAPS.wDeviceIndex);
capPreview(hWndC_CCD1,true);//使影像在視窗上顯示
Timer1->Enabled=true;
}
//---------------------------------------------------------------------------


void __fastcall TForm1::Button2Click(TObject *Sender)
{
//靜態圖做灰階
Graphics::TBitmap *pBitmap = new Graphics::TBitmap;
Byte *ptr;
unsigned int B,G,R;
int x,y;
pBitmap->Assign(Image2->Picture);
for (y = 0; y < pBitmap->Height; y )//掃圖先掃行在掃列
{ //將圖的每BITE找出來
ptr = (BYTE*)pBitmap->ScanLine[y];
for (x = 0; x < pBitmap->Width; x )
{
B=*(ptr x*3);
G=*(ptr x*3 1);
R=*(ptr x*3 2);
*(ptr x*3)=(B G R)/3; //灰階的操作式(全部相加除3)
*(ptr x*3 1)=(B G R)/3;
*(ptr x*3 2)=(B G R)/3;
}
}
Image2->Canvas->Draw(0,0,pBitmap);//畫出圖
delete pBitmap;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button3Click(TObject *Sender)

{
//背景相減
Graphics::TBitmap *pBitmap2 = new Graphics::TBitmap;
Byte *ptr2;
Graphics::TBitmap *pBitmap3 = new Graphics::TBitmap;
Byte *ptr3;
Graphics::TBitmap *pBitmap4 = new Graphics::TBitmap;
Byte *ptr4;
pBitmap2->Assign(Image2->Picture);
pBitmap3->Assign(Image1->Picture);
pBitmap4->Assign(Image3->Picture);
int x1,y1;
for (y1 = 0; y1 < 240; y1 )//掃圖先掃行在掃列
{ //將圖的每BITE找出來
ptr2 = (BYTE*)pBitmap2->ScanLine[y1];
ptr3 = (BYTE*)pBitmap3->ScanLine[y1];
ptr4 = (BYTE*)pBitmap4->ScanLine[y1];
for (x1 = 0; x1 < 320; x1 )
{
int r1=ptr2[x1*3];
int g1=ptr2[x1*3 1];
int b1=ptr2[x1*3 2];
int r2=ptr3[x1*3];
int g2=ptr3[x1*3 1];
int b2=ptr3[x1*3 2];
int gray1 = (r1 b1 g1)/3;
int gray2 = (r2 b2 g2)/3;
int sub = abs( gray1 - gray2 );
if(sub >= ScrollBar1->Position && sub <= ScrollBar2->Position)
{
sub = 0;
}
else
{
sub = 255;
}
ptr4[x1*3 ] = (Byte)sub;
ptr4[x1*3 1] = (Byte)sub;
ptr4[x1*3 2] = (Byte)sub;
}
}
Image2->Canvas->Draw(0,0,pBitmap2);
Image1->Canvas->Draw(0,0,pBitmap3);
Image3->Canvas->Draw(0,0,pBitmap4);
delete pBitmap2;
delete pBitmap3;
delete pBitmap4;

}
//---------------------------------------------------------------------------

1.錯誤訊息是?
2.有沒有試過單純的兩張影像相減是否OK?

感謝大大的回覆~~我發現錯誤的地方是不能直接用TBitmap 抓他的動態影像~感謝大大!!我有做出來了~~