Error: Undefined function 'getsnapshot' for input arguments of type 'double'.

I'm doing a program that captures a picture by pressing a button, but when I execute the code the error appears:

Undefined function 'getsnapshot' for input arguments of type 'double'.

global vid
  global work_area

a = getsnapshot(vid);
imagenGray = rgb2gray(a); 
foto = a;
    Idetector = vision.CascadeObjectDetector();
    BOX = step(Idetector,foto);
       cortar = imcrop(imagenGray,BOX(1,:));
       work_area = imresize(cortar,[64,48]);
axes(handles.axes1);
imshow(foto);
rectangle('position',BOX(1,:),'edgecolor','b','linewidth',2);

algun consejo?

[Image Analyst]

You forgot to show us the line of code where you assigned vid. It should look similar to

vidobj = videoinput(theCameraAdaptor, 1, highestResFormat);

Answer 1

[Walter Roberson]

You did not initialize the global variable vid