Kinect for Processing Library

Posted by bryan

Updates


05/07/2014 – The library is renamed again to Kinect4WinSDK in order not to use the prefix P or P5. It has been built in Windows 7, Kinect for Windows SDK 1.8, Java JRE 1.7u60 and Processing 2.2.1.

05/04/2014 – The library is renamed to P5Kinect according to suggestion from the Processing community, in order not to mix up with official Processing class.

28/03/2014 – The library is updated for the use of Kinect for Windows SDK 1.8, Java JRE 1.7u51 and Processing 2.1.1.

Introduction

The Kinect for Processing library is a Java wrapper of the Kinect for Windows SDK. And it of course, runs in Windows platform. At this moment, I have only tested in Windows 7. The following 4 functions are implemented. All images at this moment are 640 x 480.

  • Obtain the RGB image from the Kinect camera.
  • Obtain the depth image from the Kinect camera.
  • Align the RGB image with the depth image.
  • Obtain player and skeleton information.

API description

GetImage() returns a 640 x 480 ARGB PImage.

GetDepth() returns a 640 x 480 ARGB PImage. The image is, however, grey scale only. It resolution is also reduced from the original 13 bits to 8 bits for compatibility with the 256 grey scale image.

GetMask() returns a 640 x 480 ARGB PImage. The image is transparent in the background using the alpha channel. Only those areas with players are opaque with the aligned RGB images of the players.

Skeleton tracking is a bit complicated. The library will expect 3 event handlers in your Processing sketch. Each event handler uses one or two arguments of type SkeletonData (to be explained later). Each SkeletonData represents a human figure that appears, disappears or moves in front of the Kinect camera.

appearEvent – it is triggered whenever a new figure appears in front of the Kinect camera. The SkeletonData keeps the id and position information of the new figure.

disappearEvent – it is triggered whenever a tracked figure disappears from the screen. The SkeletonData keeps the id and position information of the left figure.

moveEvent – it is triggered whenever a tracked figure stays within the screen and may move around. The first SkeletonData keeps the old position information and the second SkeletonData maintains the new position information of the moving figure.

Please note that a new figure may not represent a real new human player. An existing player goes off screen and comes back may be considered as new.

Data structure description

The SkeletonData class is a subset of the NUI_SKELETON_DATA structure. It implements the following public fields:

public int trackingState;
public int dwTrackingID;
public PVector position;
public PVector[] skeletonPositions;
public int[] skeletonPositionTrackingState;

Javadoc information

Download

Example

import kinect4WinSDK.Kinect;
import kinect4WinSDK.SkeletonData;

Kinect kinect;
ArrayList  bodies;

void setup()
{
  size(640, 480);
  background(0);
  kinect = new Kinect(this);
  smooth();
  bodies = new ArrayList();
}

void draw()
{
  background(0);
  image(kinect.GetImage(), 320, 0, 320, 240);
  image(kinect.GetDepth(), 320, 240, 320, 240);
  image(kinect.GetMask(), 0, 240, 320, 240);
  for (int i=0; i=0; i--) 
    {
      if (_s.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.remove(i);
      }
    }
  }
}

void moveEvent(SkeletonData _b, SkeletonData _a) 
{
  if (_a.trackingState == Kinect.NUI_SKELETON_NOT_TRACKED) 
  {
    return;
  }
  synchronized(bodies) {
    for (int i=bodies.size ()-1; i>=0; i--) 
    {
      if (_b.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.get(i).copy(_a);
        break;
      }
    }
  }
}

Updated release of the PKinect library

Posted by bryan

Finally, I updated the original PKinect Processing library for the Microsoft Kinect camera with the latest Kinect for Windows SDK 1.8 and built with Java JRE 1.7 update 51. It was tested in the latest Processing version 2.1.1.

The testing library can be temporarily downloaded here. Place the code folder into your Processing sketch folder. The latest sources will be released in Github soon.

 

Domain Mall Interactive Wall

Posted by bryan

This is an interactive display for the Domain Mall public art project, with Otto Li. The mall is in Yau Tong, next to the MTR station. Two Kinect cameras capture the participant images to react with the animation. The season and weather information trigger further variations of the visual imageries.
 

Kinect in Windows for Processing 5

Posted by bryan

This is a more or less finished version of the Kinect for Processing library. It includes the basic skeleton tracking, the RGB image, depth image and a mask image. I shall move the related posts to the research page with more documentation on the data structure and method description. Stay tune.
 

 
The sample Processing code:

import pKinect.PKinect;
import pKinect.SkeletonData;
 
PKinect kinect;
PFont font;
ArrayList<SkeletonData> bodies;
PImage img;
 
void setup()
{
  size(640, 480);
  background(0);
  kinect = new PKinect(this);
  bodies = new ArrayList<SkeletonData>();
  smooth();
  font = loadFont("LucidaSans-18.vlw");
  textFont(font, 18);
  textAlign(CENTER);
  img = loadImage("background.png");
}
 
void draw()
{
  background(0);
  image(kinect.GetImage(), 320, 0, 320, 240);
  image(kinect.GetDepth(), 320, 240, 320, 240);
  image(img, 0, 240, 320, 240);
  image(kinect.GetMask(), 0, 240, 320, 240);
  for (int i=0; i<bodies.size(); i++) 
  {
    drawSkeleton(bodies.get(i));
    drawPosition(bodies.get(i));
  }
}
 
void mousePressed() 
{
  println(frameRate);
}
 
void drawPosition(SkeletonData _s) 
{
  noStroke();
  fill(0, 100, 255);
  String s1 = str(_s.dwTrackingID);
  text(s1, _s.position.x*width/2, _s.position.y*height/2);
}
 
void drawSkeleton(SkeletonData _s) 
{
  // Body
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HEAD, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SPINE, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT);
 
  // Left Arm
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_LEFT, 
  PKinect.NUI_SKELETON_POSITION_WRIST_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_WRIST_LEFT, 
  PKinect.NUI_SKELETON_POSITION_HAND_LEFT);
 
  // Right Arm
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_WRIST_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_WRIST_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_HAND_RIGHT);
 
  // Left Leg
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT, 
  PKinect.NUI_SKELETON_POSITION_KNEE_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_KNEE_LEFT, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_LEFT, 
  PKinect.NUI_SKELETON_POSITION_FOOT_LEFT);
 
  // Right Leg
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_KNEE_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_KNEE_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_FOOT_RIGHT);
}
 
void DrawBone(SkeletonData _s, int _j1, int _j2) 
{
  noFill();
  stroke(255, 255, 0);
  if (_s.skeletonPositionTrackingState[_j1] != PKinect.NUI_SKELETON_POSITION_NOT_TRACKED &&
    _s.skeletonPositionTrackingState[_j2] != PKinect.NUI_SKELETON_POSITION_NOT_TRACKED) {
    line(_s.skeletonPositions[_j1].x*width/2, 
    _s.skeletonPositions[_j1].y*height/2, 
    _s.skeletonPositions[_j2].x*width/2, 
    _s.skeletonPositions[_j2].y*height/2);
  }
}
 
void appearEvent(SkeletonData _s) 
{
  if (_s.trackingState == PKinect.NUI_SKELETON_NOT_TRACKED) 
  {
    return;
  }
  synchronized(bodies) {
    bodies.add(_s);
  }
}
 
void disappearEvent(SkeletonData _s) 
{
  synchronized(bodies) {
    for (int i=bodies.size()-1; i>=0; i--) 
    {
      if (_s.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.remove(i);
      }
    }
  }
}
 
void moveEvent(SkeletonData _b, SkeletonData _a) 
{
  if (_a.trackingState == PKinect.NUI_SKELETON_NOT_TRACKED) 
  {
    return;
  }
  synchronized(bodies) {
    for (int i=bodies.size()-1; i>=0; i--) 
    {
      if (_b.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.get(i).copy(_a);
        break;
      }
    }
  }
}

You can download the example and the library here.

Kinect for Windows in Processing 4

Posted by bryan

This is the new version of the Kinect for Processing library using the Kinect for Windows 1.5 SDK. In this version, I only implement the skeleton tracking, without the previous RGB image and depth image yet. For all the field, method and constant names, I try to use the same ones as in the SDK. It can have multiple skeletons and comes with three events:

  • appear (new skeleton enters the screen)
  • disappear (existing skeleton leaves the screen)
  • move (existing skeleton stay in the screen)

 

Here is the example Processing code.

import pKinect.PKinect;
 
PKinect kinect;
PFont font;
ArrayList<SkeletonData> bodies;
 
void setup()
{
  size(640, 480);
  background(0);
  kinect = new PKinect(this);
  bodies = new ArrayList<SkeletonData>();
  smooth();
  font = loadFont("LucidaSans-18.vlw");
  textFont(font, 18);
  textAlign(CENTER);
}
 
void draw()
{
  fill(0, 0, 0, 16);
  rect(0, 0, width, height);
  for (int i=0; i<bodies.size(); i++) 
  {
    drawSkeleton(bodies.get(i));
    drawPosition(bodies.get(i));
  }
}
 
void drawPosition(SkeletonData _s) 
{
  noStroke();
  fill(0, 255, 255);
  String s1 = str(_s.dwTrackingID);
  text(s1, _s.position.x*width, _s.position.y*height);
}
 
void drawSkeleton(SkeletonData _s) 
{
  // Body
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HEAD, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_CENTER, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_SPINE);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SPINE, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_CENTER, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT);
 
  // Left Arm
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_LEFT, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_LEFT, 
  PKinect.NUI_SKELETON_POSITION_WRIST_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_WRIST_LEFT, 
  PKinect.NUI_SKELETON_POSITION_HAND_LEFT);
 
  // Right Arm
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_SHOULDER_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ELBOW_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_WRIST_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_WRIST_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_HAND_RIGHT);
 
  // Left Leg
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_LEFT, 
  PKinect.NUI_SKELETON_POSITION_KNEE_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_KNEE_LEFT, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_LEFT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_LEFT, 
  PKinect.NUI_SKELETON_POSITION_FOOT_LEFT);
 
  // Right Leg
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_HIP_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_KNEE_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_KNEE_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_RIGHT);
  DrawBone(_s, 
  PKinect.NUI_SKELETON_POSITION_ANKLE_RIGHT, 
  PKinect.NUI_SKELETON_POSITION_FOOT_RIGHT);
}
 
void DrawBone(SkeletonData _s, int _j1, int _j2) 
{
  noFill();
  stroke(255, 200, 0);
  if (_s.skeletonPositionTrackingState[_j1] != PKinect.NUI_SKELETON_POSITION_NOT_TRACKED &&
    _s.skeletonPositionTrackingState[_j2] != PKinect.NUI_SKELETON_POSITION_NOT_TRACKED) {
    line(_s.skeletonPositions[_j1].x*width, 
    _s.skeletonPositions[_j1].y*height, 
    _s.skeletonPositions[_j2].x*width, 
    _s.skeletonPositions[_j2].y*height);
  }
}
 
void appearEvent(SkeletonData _s) 
{
  if (_s.trackingState == PKinect.NUI_SKELETON_NOT_TRACKED) 
  {
    return;
  }
  synchronized(bodies) {
    bodies.add(_s);
  }
  println("appearing ..." + _s.dwTrackingID);
}
 
void disappearEvent(SkeletonData _s) 
{
  synchronized(bodies) {
    for (int i=bodies.size()-1; i>=0; i--) 
    {
      if (_s.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.remove(i);
      }
    }
  }
  println("Disappearing ... " + _s.dwTrackingID);
}
 
void moveEvent(SkeletonData _b, SkeletonData _a) 
{
  if (_a.trackingState == PKinect.NUI_SKELETON_NOT_TRACKED) 
  {
    return;
  }
  synchronized(bodies) {
    for (int i=bodies.size()-1; i>=0; i--) 
    {
      if (_b.dwTrackingID == bodies.get(i).dwTrackingID) 
      {
        bodies.get(i).copy(_a);
        break;
      }
    }
  }
}

 
The Processing code and library can be downloaded here.