pixel smoothing and moving average in javascript, for Kinect depth frame buffers in https://github.com/whichlight/figure-sketching-kinect/

kinect-depth-smoothing.js

//from http://www.codeproject.com/Articles/317974/KinectDepthSmoothing

function smoothDepth(arr){
  var res = createArray(width,height);
  for(var i=2; i< width-2; i++){
    for(var j=2; j < height-2; j++){
      if(arr[i][j]===0){
        var innerBandCount = 0;
        var outerBandCount = 0;
        var filterCollection = [];

        for (var y = -2; y < 3; y++)
        {
          for (var x = -2; x < 3; x++)
          {
            if (x != 0 || y != 0)
            {
              var i2 = i + x;
              var j2 = j + y;
              if(arr[i2][j2]!=0){
                filterCollection.push(arr[i2][j2]);
                if (y != 2 && y != -2 && x != 2 && x != -2){
                  innerBandCount++;
                }
                else{
                  outerBandCount++;
                }

              }
            }
          }
        }
        if (innerBandCount >= innerBandThreshold || outerBandCount >= outerBandThreshold)
        {
          res[i][j] = mode(filterCollection);
        }
        else{
          res[i][j] = arr[i][j];
        }
      }
      else{
        res[i][j] = arr[i][j];
      }
    }
  }
  return res;
}

function movingAverage(arr, movingAverageWindow){
  depthQueue.push(arr);

  if (depthQueue.length > movingAverageWindow){
    depthQueue.shift();
  }

  var denominator = 0;
  var count = 1;
  var sumDepthArray = createArray(width,height);
  var averagedDepthArray = createArray(width,height);

  for(var i=0; i<width; i++){
    for( var j=0; j<height; j++){
      sumDepthArray[i][j] =0;
    }
  }

  for(var layer=depthQueue.length-1; layer >=0 ; layer--){
    for(var i=0; i<width; i++){
      for( var j=0; j<height; j++){
        sumDepthArray[i][j] += depthQueue[layer][i][j] * count;
      }
    }
    denominator+=count;
    count++;
  }
  for(var i=0; i<width; i++){
    for( var j=0; j<height; j++){
      averagedDepthArray[i][j] = sumDepthArray[i][j]/denominator;
    }
  }
  return averagedDepthArray;
}