Add an "orb" step to your pipeline, then capture a template to enable object tracking.
blur - Gaussian blur filter
thresh - Binary threshold
adaptive - Adaptive threshold
erode/dilate - Morphological operations
sobel - Edge detection
otsu - Automatic threshold selection
blobs - Connected component analysis (red boxes)
keypoints - FAST corner detection (green circles)
orb - ORB features with orientation (blue circles with lines)
contours - Boundary tracing (colored boxes with length info)