Matlab Imshow command does not show the same binary image with original

I read the image with:

   W=double(imread('rose32.bmp'));

Then: imshow(W,[]); or imshow(W);

But, Showed image seems to invert of original image. How Can I solve this problem ? It is a Matlab problem ?

Answer 1

[Walter Roberson]

You are treating the image as if it is a binary or RGB image, but it is not: it is an index (pseudocolor) image. You can see this by using

iminfo('rose32.bmp')

and noticing the "ColorType: 'indexed'"

A proper way to display it:

[W,cmap]=imread('rose32.bmp');
image(ind2rgb(W,cmap))

[Mevlut Dogru]

Below code running. But iminfo function do not working at Matlab 2010. Do you know of this reason ?

[Walter Roberson]

sorry, should be imfinfo()

[Mevlut Dogru]

for Gri Level image imfinfo('Lena.gif') command shows "ColorType: 'indexed'" is it true ?

[Walter Roberson]

If the Colormap shows up as nonempty then it is a pseudo color image not a grayscale image. .gif are mostly pseudo color.