error using imfinfo()

When I using imfinfo() function for finding bit depth of an image it shows an error messege that my image is in uni8 type and image should be in char or string type.What can I do now? please help someone. Its very urgent.

Answer 1

[Walter Roberson]

Images in memory such as your compareimages do not have a "bitdepth", and cannot be queried with imfinfo()

Before you while loop, do

filenames = ds.Files;

Then change

info = imfinfo( compareimages);

to

thisfile = filenames{k};
info = imfinfo(thisfile);

[Sajitha K.N.]

ds.Files here am I want to put ds.compareimages?

[Sajitha K.N.]

I want to find bit depth of compareimages

[Walter Roberson]

Oh, here it is. You have

outputimage1 = im2uint8(filtered_3x3);
outputimage2 = im2uint8(filtered_3x3);

so no matter what the bit depth of the input image, your outputimage1 and outputimage2 are 8 bit. You then

compareimages = imabsdiff(outputimage2,outputimage1);

The result of imabsdiff() of two uint8 images is uint8 . Therefore the bit depth of compareimages is 8 no matter what the input files were.

It is possible that you will not need the full 8 bits to represent the result, but that is a different question. For example if you have an input image that consisted only of values 0 and 255, then each location could be encoded as a single bit for a bit depth of 1, but would still require a bit depth of 8 because of the way that the image is stored.