Can you get the maximal intensity of an frame in preview

I am using preview for having an live feed of the camera. I would like to also display the maximal intensity of each frame with the streaming video. The maximal intensity is to be sent to app.MaxIntensityStream.Value.

My code for dispalying preview:

                [app.img, app.ts] = snapshot(app.g);
                app.imHandle = imagesc(app.UIAxes, app.img);
                axis(app.UIAxes,'image')
                app.hdata = preview(app.g, app.imHandle);  % app.hdata.CData
                app.MaxIntensityStream.Value = double(max(max(max(app.imHandle.CData))));
                

But its not showing any intensity change during the video feed or when i change the exposure time of camera handle app.g, only shows the intensity in the first frame (as it seems).

What am I doing wrong?

Thanks!

[Kevin Holly]

If you stop it, does it update? If so, you may need to add

drawnow

after updating frames.

[Happy PhD]

I tried that but it doesn't work. I don't stop the preview. How can You make that work?

Answer 1

[Happy PhD]

Problem was solved by taking snapshot and find the maximal value in the frame.