How to average values of more frames in Processing

Geonik84

I'm working on this code to manage and save data coming from the Microsoft kinect, the data are stored in the int array int[] depthValues, what I'd like to do is to store and save an average of more frames (let's say 10), in order to get smoother data, leaving the remaining part of the code as it is.

Here's the code:

import java.io.File;
import SimpleOpenNI.*;
import java.util.*;
SimpleOpenNI kinect;
void setup()
{
  size(640, 480);
  kinect = new SimpleOpenNI(this);
  kinect.enableDepth();
}
int precedente = millis();
void draw()
{
  kinect.update();
  PImage depthImage = kinect.depthImage();
  image(depthImage, 0, 0);
  int[] depthValues = kinect.depthMap();
  //depthValues = reverse(depthValues);
  StringBuilder sb = new StringBuilder();
  Deque<Integer> row = new LinkedList<Integer>();
  int kinectheight = 770; // kinect distance from the baselevel [mm]
  int scaleFactor = 1;
  int pixelsPerRow = 640;
  int pixelsToSkip = 40;
  int rowNum = 0;
  for (int i = 0; i < depthValues.length; i++) {
    if (i > 0 && i == (rowNum + 1) * pixelsPerRow) {
      fillStringBuilder(sb, row);
      rowNum++;
      sb.append("\n");
      row = new LinkedList<Integer>();
    }
    if (i >= (rowNum * pixelsPerRow) + pixelsToSkip) {
      row.addFirst((kinectheight - depthValues[i]) * scaleFactor);
    }
  }
  fillStringBuilder(sb, row);
  String kinectDEM = sb.toString();
  final String[] txt= new String[1]; //creates a string array of 2 elements
  int savingtimestep = 15000;  // time step in millisec between each saving
  if (millis() > precedente + savingtimestep) {
    txt[0] = "ncols         600\nnrows         480\nxllcorner     0\nyllcorner     0\ncellsize      91.6667\nNODATA_value  10\n" +kinectDEM;
    saveStrings("kinectDEM0.tmp", txt);
    precedente = millis();
    //  delete the old .txt file, from kinectDEM1 to kinectDEMtrash
    File f = new File (sketchPath("kinectDEM1.txt"));
    boolean success = f.delete();

    //  rename the old .txt file, from kinectDEM0 to kinectDEM1
    File oldName1 = new File(sketchPath("kinectDEM0.txt"));
    File newName1 = new File(sketchPath("kinectDEM1.txt"));
    oldName1.renameTo(newName1);
    //  rename kinectDEM0.tmp file to kinectDEM0.txt
    File oldName2 = new File(sketchPath("kinectDEM0.tmp"));
    File newName2 = new File(sketchPath("kinectDEM0.txt"));
    oldName2.renameTo(newName2);

  }
}
void fillStringBuilder(StringBuilder sb, Deque<Integer> row) {
  boolean emptyRow = false;
  while (!emptyRow) {
    Integer val = row.pollFirst();
    if (val == null) {
      emptyRow = true;
    } else {
      sb.append(val);
      val = row.peekFirst();
      if (val != null) {
        sb.append(" ");
      }
    }
  }
}