if not proc.BeginImageProcessing([ie24RGB], x1, y1, x2, y2, 'CustomNegative', ProcBitmap, mask) then
    exit;
  for y := y1 to y2-1 do begin
    px := ProcBitmap.Scanline[y];
    for x := x1 to x2-1 do
    begin
      with px^ do
      begin
        r := 255-r;
        g := 255-g;
        b := 255-b;
      end;
      inc(px);
    end;
  end;
  // finalize
  proc.EndImageProcessing(ProcBitmap, mask);

void __fastcall TImageForm::UpdateImagePixels(WINSTRETCHPARAS &winStrechPara)
{
	TIEBitmap *ProcBitmap;
	TIEMask *mask;
	int x1, y1, x2, y2;
	if (!ImgEnMain->Proc->BeginImageProcessing(Hyiedefs::TIEPixelFormats()<<ie24RGB,
		x1, y1, x2, y2, "FloatStrech", ProcBitmap, mask))
		return;
int CPUCoreCount = ImageParas.CPUCoreCount;
    std::vector<std::thread> threads;
    const int chunkSize = (y2 - y1) / CPUCoreCount; // 
	TIERectangle  sel;
	sel = ImgEnMain->SelectedRect;
    for (int i = 0; i < CPUCoreCount; ++i) {
        int start = i * chunkSize;
        int end = (i == CPUCoreCount - 1) ?  (y2 - y1) : start + chunkSize;
        threads.push_back(std::thread(ppkSetBlockPixels, std::ref(ImgEnMain),  std::ref(RImage),
        	std::ref(mask), std::ref(sel), 	std::ref(winStrechPara), start, end, x1, x2));
    }
	ImgEnMain->Proc->EndImageProcessing(ProcBitmap, mask);
}
int __fastcall TImageForm::ppkSetBlockPixels(TImageEnView *imgen, TEImage *RImage,  TIEMask *mask,
							TIERectangle  &sel, WINSTRETCHPARAS &winStrechPara,
                            int startln, int endln, int startr, int endr)
{
    unsigned short xyGray;
    Hyiedefs::PRGB px;
    int x,y;
    Hyiedefs::TRGB tmppx;
    px = &tmppx;
	for (int i = startln; i < endln; i++) {
		y = sel.y + i;
		for (int j = startr; j <= endr; j++) {
			x = sel.x + j;
            xyGray = RImage->ProcData[y][x] * FIMGScale;
	
			if (winStrechPara.mbGrayStrech) {
				xyGray = winStrechPara.GrayHisto[xyGray];
			}
			if (winStrechPara.mbWindowedShow) {
				if (xyGray < winStrechPara.GWinLowvalue) {
					xyGray = 0;
				}
				if (xyGray > winStrechPara.GWinUpvalue) {
					xyGray = 255;
				}
			}
            if (imgen->Selected){
            	if(mask->GetPixel(x, y) > 0) {
                	setPixelColor(px, xyGray);
                    imgen->IEBitmap->Pixels_ie24RGB[x][y] = *px;
                }
			}else{
				setPixelColor(px, xyGray);
                imgen->IEBitmap->Pixels_ie24RGB[x][y] = *px;
            }
		}
	}
    return 1;
}