Detecting white color in moving video

Question

KDN 2015-11-8

评论： Image Analyst 2015-11-9

What change I have to do in given code below to detect white color from video and get it's brightness.

snap_red = imsubtract(snap(:,:,1), rgb2gray(snap));

Answer 1

Image Analyst 2015-11-8

hsvImage = rgb2hsv(double(rgbImage));
h = hsvImage(:,:,1);
s = hsvImage(:,:,2);
v = hsvImage(:,:,3);
whitePixels = s < 0.2 & v > 0.8;

or something like that.

whitePixels is a binary image, or "mask". Feel free to modify the parameters.

See my demo where I track a green Sharpie pen.

KDN 2015-11-9

编辑：KDN 2015-11-9

Thanks nice work, but I am getting error while running video.

Image Analyst 2015-11-9

It works for me. Was that for my demo video, or for one of yours? If you put a breakpoint on this line and execute it,

% Setup other parameters
numberOfFrames = videoObject.NumberOfFrame;

what does it say numberOfFrames is? Is the videoObject a valid object?