/**
* Updates the positions and state of eyes to the underlying graphic, according to the most recent
* face detection results. The graphic will render the eyes and simulate the motion of the iris
* based upon these changes over time.
*/
@Override
public void onUpdate(FaceDetector.Detections<Face> detectionResults, Face face) {
mOverlay.add(mEyesGraphic);
updatePreviousProportions(face);
PointF leftPosition = getLandmarkPosition(face, Landmark.LEFT_EYE);
PointF rightPosition = getLandmarkPosition(face, Landmark.RIGHT_EYE);
float leftOpenScore = face.getIsLeftEyeOpenProbability();
boolean isLeftOpen;
if (leftOpenScore == Face.UNCOMPUTED_PROBABILITY) {
isLeftOpen = mPreviousIsLeftOpen;
} else {
isLeftOpen = (leftOpenScore > EYE_CLOSED_THRESHOLD);
mPreviousIsLeftOpen = isLeftOpen;
}
float rightOpenScore = face.getIsRightEyeOpenProbability();
boolean isRightOpen;
if (rightOpenScore == Face.UNCOMPUTED_PROBABILITY) {
isRightOpen = mPreviousIsRightOpen;
} else {
isRightOpen = (rightOpenScore > EYE_CLOSED_THRESHOLD);
mPreviousIsRightOpen = isRightOpen;
}
mEyesGraphic.updateEyes(leftPosition, isLeftOpen, rightPosition, isRightOpen);
}
private void updatePreviousProportions(Face face) {
for (Landmark landmark : face.getLandmarks()) {
PointF position = landmark.getPosition();
float xProp = (position.x - face.getPosition().x) / face.getWidth();
float yProp = (position.y - face.getPosition().y) / face.getHeight();
mPreviousProportions.put(landmark.getType(), new PointF(xProp, yProp));
}
}
/**
* Finds a specific landmark position, or approximates the position based on past observations if
* it is not present.
*/
private PointF getLandmarkPosition(Face face, int landmarkId) {
for (Landmark landmark : face.getLandmarks()) {
if (landmark.getType() == landmarkId) {
return landmark.getPosition();
}
}
PointF prop = mPreviousProportions.get(landmarkId);
if (prop == null) {
return null;
}
float x = face.getPosition().x + (prop.x * face.getWidth());
float y = face.getPosition().y + (prop.y * face.getHeight());
return new PointF(x, y);
}