matlab 图像的扫描显示

本以为MATLAB的图像扫描显示很简单，先创建一个三维数组A，全部赋值为255（显示为白色），然后读入图像数组B，将B的元素逐行赋值给A,每赋值一次，显示A一次，中间停顿0.01秒即可。想得简单，做起来必然复杂，程序完成后，提示：Error using ==> image
TrueColor CData contains element out of range 0.0 <= value <= 1.0。imshow()函数可以运行，但完全不是我想要的结果，百思不得其解，那是个崩溃啊。做了半天无用空，决定还是从MATLAB的文档看起，help image,选中doc image,看了一眼，立刻有所醒悟：
When you read image data into MATLAB using imread, the data is usually stored as an array of 8-bit integers. However, imread also supports reading 16-bit-per-pixel data from TIFF and PNG files. These are more efficient storage methods than the double-precision (64-bit) floating-point numbers that MATLAB typically uses. However, it is necessary for MATLAB to interpret 8-bit and 16-bit image data differently from 64-bit data. This table summarizes these differences.

Image TypeDouble-Precision Data
(double Array)8-Bit Data (uint8 Array)
true color (RGB)Image is stored as a three-dimensional(m-by-n-by-3 http://www.liangpinwu.com) array of floating-point values in the range [0, 1].Image is stored as a three-dimensional (m-by-n-by-3) array of integers in the range [0, 255] (uint8) or [0, 65535] (uint16).
回到命令行，输入whos回车，显示如下：

Name       Size                           Bytes  Class

  Img      140x102x3                        42840  uint8 array
  Img1     140x102x3                       342720  double array
  a          1x1                                8  double array
  b          1x1                                8  double array
  c          1x1                                8  double array
  i          1x1                                8  double array
  j          1x1                                8  double array
  k          1x1                                8  double array
  x          1x1                                8  double array

原来在程序里定义的变量都是 double array，而读入的图像却是uint8,ok,将double array转变为uint8即可，保存，运行，完全没有问题，现将程序源码附上，望有助于需要的朋友。

Img=imread('D:/Backup/我的文档/美景6.jpg');  %读入图像

x=size(Img,1);

for a=1:x
    for b=1:size(Img,2)
        for c=1:3
            Img1(a,b,c)=255；
           
        end
    end
end
Img1=uint8(Img1);          %将double array 转为 uint8
for i=1:x
    for j=1:size(Img,2)
        for k=1:3
           
    Img1(i,j,k)=Img(i,j,k);
  
end
    end

    image(Img1);          %显示图像

    pause(0.01);          %程序停留0.01秒
end