Plot image in 3D and ignore certain values

I’d like to visualise the following image (see the image) in 3D without showing the blue part (see the 3D plot). The image is basically a plane where the white part has intensity values ranging from 247 to 252. The black part has intensity value 0. Please find the image in the attachment.

Image:

3D plot:

Here is the code I am using to visualize the image in 3D:

Img_8Bit = imread('Image-1.png');

figure
surf(Img_8Bit,'EdgeColor','none');

Any suggestions?

Answer 1

[Rik]

If you switch to double, you can set the zeros to NaN, which will be hidden by surf. You'll then have to adjust the axis limits and color axis limits.

Img_8Bit = imread('Image-1.png');

Img_double=double(Img_8Bit);
Img_double(Img_double==0)=NaN;

figure(1),clf(1)
surf(Img_double,'EdgeColor','none');
axlims=[1 size(Img_double,2) 1 size(Img_double,1) 0 255];
caxis([0 255]),axis(axlims)

[Tariqul]

Great, works nicely!