How can I find mean crossing irregularity?

I have a sound file that contains 144000 data points. Thanks to the buffer language, I was able to break this file into windows. For each of these windows, I'd like to calculate the mean crossing irregularity. If X is the random variable for the interval between two consecutive mean crossing indices, then The ratio of this variable's standard deviation to its mean value is known as mean crossing irregularity. I'm trying to figure out what this ratio is for both of these windows. Can you help me?

sound=structWheeze(2,1).SoundData;
piece = 400;
overlap = 200;
frames = buffer(sound, piece, overlap);
for k1 = 1:fix(size(frames,2)/10)
x = 1:length(sound);                                             
zci = @(v) find(v(:).*circshift(v(:), [-1 0]) <= 0);           
dy = zci(sound);                                                 
for k1 = 1:size(dy,1)-1
    b = [[1;1] [x(dy(k1)); x(dy(k1)+1)]]\[sound(dy(k1)); sound(dy(k1)+1)];   
    x0(k1) = -b(1)/b(2);                         
end
end

Answer 1

[dpb]

z=randn(1,1000);        % sample dataset
zs=(detrend(z)>0);      % convert to binary at mean
iz=diff(find([0 zs]));  % crossings distances
mci=std(iz)/mean(iz);   % desired statistic