matlab 图像配准问题，有代码，配准区域是绿色的，想要的是灰度图像的配准区域，求助大神？

  fixed  = rgb2gray(imread('1-60.bmp'));
  moving = rgb2gray(imread('1-120.bmp'));

  % View misaligned images 图片不一致
  figure,imshowpair(fixed, moving,'blend','Scaling','independent');
  title('两图差别');

  % Get a configuration suitable for registering images from different
  % sensors.
  [optimizer, metric] = imregconfig('monomodal');

  % Tune the properties of the optimizer to allow for more iterations
  % and reduce the initial step size we will take in parameter space so
  % that the registration will converge to a global maxima of mutual
  % information.
   optimizer.MaximumIterations = 300;  %最大迭代次数
%   optimizer.InitialRadius = 3.5e-3;

  % Align the moving image with the fixed image
  movingRegistered = imregister(moving, fixed, 'affine', optimizer, metric);
  % View registered images
  figure,
  imshowpair(fixed, movingRegistered,'Scaling','joint');
  title('配准完成');

  set(gca,'units','pixels','Visible','off');
frame=getframe;
im1=frame2im(frame);
imwrite(im1,'peizhun0.jpg','jpg');


想求助下怎么把 配准图片配准区域是原灰度值图片而不是绿色的？？？