faceDetectionToRoi function
Expands a face bounding box and turns it into a square ROI suitable for face mesh alignment.
Implementation
RectF faceDetectionToRoi(RectF boundingBox, {double expandFraction = 0.6}) {
final RectF e = boundingBox.expand(expandFraction);
final double cx = (e.xmin + e.xmax) * 0.5;
final double cy = (e.ymin + e.ymax) * 0.5;
final double s = math.max(e.w, e.h) * 0.5;
return RectF(cx - s, cy - s, cx + s, cy + s);
}