MATLAB: How to add a histogram to a live video preview

Question

Hi I'm working on a project where I've created a custom GUI and connected the axes (axes1) to an external camera when a button is pushed and on the same button push a live histogram of the preview image should come up in a different axes. I have gotten the preview to appear and the histogram to appear, however, the histogram does not update itself automatically when the preview image is changed. I've tried everything and need a direction to go on with this. Here's my code below for just the button I'm trying to get working:

 function pushbutton1_Callback(hObject, eventdata, handles)
 handles = guidata(hObject);
 imaqmex('feature', '-previewFullBitDepth', true);
 axes(handles.axes1)
 vid = videoinput('Camera_source_1', 1, 'MONO16_BIN2x2_1024x1024_SlowMode');
 src = getselectedsource(vid);
 vidres = vid.VideoResolution;
 imWidth = vidres(1);
 imHeight = vidres(2);
 nBands = vid.NumberOfBands;
 himage = image(zeros(imHeight,imWidth, nBands), 'Parent', handles.axes1);
 figSize = get(handles.axes1, 'Position');
 figWidth = figSize(3);
 figHeight = figSize(4);
 gca.unit = 'pixels';
 gca.position = [((figWidth - imWidth)./2)...
                ((figHeight - imHeight)./2)...
                imWidth imHeight];
 vid.FramesPerTrigger = Inf;
 src.ExposureTime = user_val(1);
 im = preview(vid, himage);
 ax = im.Parent;
 im.CDataMapping = 'scaled';
 colormap(ax, gray);
 signalRange = [30 2000];
 ax.CLim = signalRange;
 axes(handles.axes2)
 himage.CData = im.CData;
 set(himage, 'CData', im.CData);
 imhist(himage.CData, 128)
 grid on
 grid minor
 drawnow
 preview(vid, himage)
 guidata(hObject, handles);

Answer 1

I think you're going to have to get a snapshot with getsnapshot() and then histogram that.