Need a fast way to create a counter variable

I'm trying to find a faster way to calculate the time a time series data set is at a particular value. Here is my code (but i KNOW theres gotta be a better way to do this? using diff maybe?) Any ideas on how to make this faster? I need help in the middle section (not the initialization or the plotting)

%Create a sample set of data
time = 0:.12:(.12*10000 - .12);
data = zeros(10000,1);
data(2:100,1) = 1;
data(400:500,1) = 1;
value = 0;
timestep = 0.12;

%%This part will look at time series data and create a variable showing how long the variable has been active

%Initialize
currently_counting = 0;
counter_channel = zeros(size(data));
data_meets_conditions = find(data==value);

%For all of the data
for i = 1:size(data_meets_conditions,1)

      %Current index of the data channel that you are going through...
      cur_data_index = data_meets_conditions(i);

      if currently_counting == 1;
          %Use the last counter channel and add a time value to it.
          counter_channel(cur_data_index) = counter_channel(cur_data_index-1) + timestep;
      end

      %Used for the very first case
      min_index = max(1,cur_data_index-1);

      if data(cur_data_index) == data(min_index)
          %Start counting
          currently_counting = 1;
      else
          currently_counting = 0;
      end
  end

%%Plotting
figure
subplot(2,1,1);
plot(time,data)
subplot(2,1,2);
plot(time,counter_channel)

Answer 1

[Image Analyst]

If you have the Image Processing Toolbox (type ver on the command line to check), you can do that in like one line or two lines with regionprops().