Kinect V2 Depth Changes

Hi All,

I am currently working with the Kinect V2 to develop a method of tracking respiratory motion.

How can I model and plot the depth changes over time? From looking into the array the depth image stores, the depth seems to be an index between the height and width.

For simplicity I want to plot the depth changes of a 5x5 pixel square in the center of the screen over 300 frames, so roughly 10 seconds. (I'll change the frequency to fixed 10 Hz later) but right now i'm stuck on the basics.

Any help would be appreciated!

Thank you in advance.

Answer 1

[Walter Roberson]

maxFrame = 300;
vid = videoinput('kinect', 2);   %1 for color, 2 for depth
vid.FramesPerTrigger = 1;
vid.TriggerRepeat = maxFrame;
start(vid);
for nFrame = 1 : maxFrame
    d = getdata(vid);
    [h,w,p] = size(d);
    hh = floor(h/2);
    hw = floor(w/2);
    d55 = d(hh-2:hh+2, hw-2:hw+2,:);
    ...
end

[Anthony Foti]

Hey Walter,

Thank you for the quick reply!

I am receiving an error "Index in position 1 exceeds array bounds (must not exceed

424)."

[Walter Roberson]

I have adjusted the code. You might want to double-check the behavior on even vs odd sized matrices as to what it means to take a " 5x5 pixel square in the center of the screen"

[Anthony Foti]

Sorry, reading that back makes it sound silly. I appreicate and have accepted your answer!

[Walter Roberson]

No it isn't silly: it is just that typically the arrays are even length and then it becomes a challenge to say what the center pixel is.