colorbar not matching disparity image values

I calculated a disparity image. Plotting this image, i use the following basic code:

figure

imshow(dispa)

title('Disparity Map1')

colormap jet

colorbar

The disparity image is a variable of type 478x638 double.

The result of the given plotting code shows me a colorbar, which does not match the colorbar:

I displayed an example DataTip. The 'value' of this pixel ist 38.5105. The colorbar is still going from 0 to 1.

If i extend the colorbar range, the colorbar becomes nearly completely red:

How can i display the disparity image with a suitable colorbar next to the disparity image?

[Jonas]

did you try imagesc() instead of imshow()?

Answer 1

[Yash]

Hi Ozan,

I understand that you are facing issues while plotting a disparity image using the "imshow" function.

According to the documentation (https://www.mathworks.com/help/images/ref/imshow.html), the function "imshow" uses the default display range for the image data type and optimizes figure, axes, and image object properties for image display. In this case, the default range is set from 0 to 1.

To address this issue, you can modify the default display range by providing the "DisplayRange" argument to the "imshow" function. For more information on how to use this argument, you can refer to the documentation at the following link: https://www.mathworks.com/help/images/ref/imshow.html#bvmnrxi-1-DisplayRange

You can modify the code to set the display range as shown below:

figure
imshow(dispa,[0 max(dispa)])
title('Disparity Map1')
colormap jet
colorbar

Alternatively, you can use the "imagesc" function to plot the image. The "imagesc" function displays the data in an array as an image, utilizing the full range of colors in the colormap. You can find more details about the "imagesc" function in the MATLAB documentation at the following link: https://www.mathworks.com/help/matlab/ref/imagesc.html

I hope this resolves the issue faced by you.