how to convert this image to the original one?

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I am using 
imshow(filename) 

I also used map and ind2rgb, but these two are also not helping me to get back the original image(image 2).
Need your help...help me.

Answer 1

[Image Analyst]

You can't get back to the original, unless you'ved save the original. If you pseudocolor the image with rgb2ind() you basically force all pixels to be chosen from a limited number of colors, and you get a "grayscale" image where the "gray scale" or value of the image is not really a gray scale intensity or a color but really an index into a pseudocolor look up table (a "colormap"). After that, then you cannot get back the original image even with ind2rgb(). ind2rgb() will give you a color image but just with the limited number of colors.