32bits save as int32

Hi there,

I have a 32bit tif image https://we.tl/t-H0WliT3O50 . This image is 'single' but Matlab assumes by default 32bit means int32 and when the image is open with imread() the image is binary. I would to read the image using grey scale. How can I do this? I´ve tried itconvert in double but the image is open as binary image.

Any help would be very much appreciated , thanks

[Ameer Hamza]

In R2020a, MATLAB reads the image as uint32, and imshow shows it correctly as a grayscale image

img = imread('lh.average.CURVATURE.tif');
imshow(img);

Can you show the code to read the image? Also, can you show the output of

class(img)

where img is variable in which image is loaded.

[Pamela Garcia]

Thanks for answer quickly.

I would to see the image like this https://we.tl/t-VCQDOLoBcr but imread() open as binary

https://we.tl/t-QQaKiKxDul

The result of class(img)

ans =

'int32'

[Ameer Hamza]

Which MATLAB release are you using?

[Pamela Garcia]

Matlab R2020a

[Ameer Hamza]

I am also using R2020a, and it reads the tiff image as uint32. Also, does the tiff and png files you shared corresponds to the same image?

[Pamela Garcia]

Yes, I just updated the images and the initial file.

[Ameer Hamza]

This tiff file seems to have very unusual encoding. How did you generate the png file from the tiff file?

[Pamela Garcia]

It is the result of windows photo visualizer

Answer 1

[Walter Roberson]

If you look at imfinfo() of the file, you can see that the headers say it is a collection of nine images with 32 bit signed integer. If it is intended to be single instead, then the metadata is wrong.

for IDX = 1 : 9
    imgint32 = imread('lh.average.CURVATURE.tif','index',IDX);
    imgsingle{IDX} = reshape(typecast(imgint32(:), 'single'), size(img32));
end

[Pamela Garcia]

Thank's a lot !