Tracking only a left or right hand

eaglface 2014-06-15 11:08:57 UTC #1

Hi there,

Is it possible to force detecting one hand, left or right one?

I'm developing software using the new skeletal tracking sdk, and I only need to track my right hand. I'm able to check if the detection is regarded as a left/right hand, but sometimes (frequently) the sdk confuses if the hand is left, and the detection results are flip-flopping btw left and right. I think if the detector assures if the hand is right, it may detect the hand without the flip-flopping.

does anyone know how to disable detecting left hand?

Thanks,

Badger99 2014-06-15 11:34:10 UTC #2

Please be more specific. What language are you coding in?
But here's how in JavaScript:

You can detect which hand is being held up by using hand.type

In context:Leap.loop(function(frame) { frame.hands.forEach(function(hand,index) { if(hand.type=="right"){ //do your stuff here } }); }).use('screenPosition', {scale: 0.25});

eaglface 2014-06-16 02:46:56 UTC #3

Thanks for the reply. I'm using C++ on Windows 7/MSVC.

The code that you show is exactly what I'm doing now. The problem is that the leap sdk sometimes confuses the right hand as a left hand, and the later processing ("// do your stuff here" part) can not be run and thus, the processing looks stuck because there is no "right" hand estimation.

What I asked is that is there a way to track only a right hand (meaning not even detecting any left hand at all) to reduce the confusion.

I feel that the hand detection/tracking uses some prior knowledge such as position. Though I did not evaluate it, it seems to prefer a pose with the palm downward to one upward, (which will make a left/right confusion.) Also the right hand detection/tracking works better on the sensor's right side than on its left side. Thus I think that if we can "turn off" the left hand detection, the single right hand detection performs much better.

Is it clearer? Any idea will be appreciated.

hackerpoet 2014-06-17 23:03:37 UTC #4

In the Leap Control Panel, try turning on "optimize for top-down tracking". This should help reduce the amount of incidents where hands incorrectly classify as left or right, especially when palms are facing upwards.

We do not support forcing a single hand chirality in tracking. As tracking improves, there will be fewer and fewer misclassifications (and faster corrections if it does misclassify) so filtering by hand type should be sufficient by the time we exit Beta.

ieysimurra 2022-10-20 17:12:50 UTC #5

Hi Guys,

I know this thread is a little old, but I just got a Leap Motion

Taking advantage of this thread on this topic, I would like to ask for help with Leap Motion in Java Processing to detect only the right hand independently of the left hand.

From the code below I can retrieve both hands only if the left was detected at first. I'd like to make the right one more autonomous.

Any help will be so appreciated. Thank you!

    import com.leapmotion.leap.*;

Controller controller = new Controller();

void setup() {
  size( displayWidth, displayHeight );
}

void draw() {
  background(0);

  InteractionBox iBox = controller.frame().interactionBox();

  HandList hands = controller.frame().hands();

  Hand leftHand = hands.get(0);
  Arm leftArm = leftHand.arm();
  Hand leftMost = hands.leftmost();

  Hand rightHand = hands.get(1);
  Arm rightArm = rightHand.arm();
  Hand rightMost = hands.rightmost();

  Vector filteredHandPositionL = leftHand.stabilizedPalmPosition();
  Vector normalizedPointL = iBox.normalizePoint(filteredHandPositionL, true);

  Vector filteredHandPositionR = rightHand.stabilizedPalmPosition();
  Vector normalizedPointR = iBox.normalizePoint(filteredHandPositionR, true);

  float leftX = normalizedPointL.getX() * width;
  float leftY = (1 - normalizedPointL.getY()) * height;

  float rightX = normalizedPointR.getX() * width;
  float rightY = (1 - normalizedPointR.getY()) * height;

  println(rightX, rightY);

  if (rightMost.isRight()) {//secondHand.isRight()) {
    fill(255, 0, 255);
    ellipse(rightX, rightY, 45, 45);
  }

  pushMatrix();
  if (leftHand.isLeft()) {
    fill(255, 0, 0);
    ellipse(leftX, leftY, 45, 45);
  }
  popMatrix();
}

Thank you guys for any help!
Cheers!