Some opencv testing code

I made a little module to have a more controlled and programmatic testing of tracking algorithms and stuff.

I could use real world data, like a video recording, but I’d like to start here. I think this is smart. I also could have used a more complicated 3d imaging package. vpython makes sense, since it is easy, but getting programmatic access to the images in unsupported somehow as far as I can tell. Now, there is no way something that might work here will necessarily transfer over to real video even after I add noise and point mismatch, but it should simplify some things. I’ve been having more trouble than makes sense to me getting good rotations off of a KLT tracker that is clearly doing a pretty bang up job.


import cv2
import numpy as np

class MyCam():
	def __init__(self, frameSize=(480,640), focus =600, avgPointPos=np.array([0,0,3]), sigma = .5, pointNum=300):
		self.pointCloud = sigma * np.random.randn(pointNum, 3)
		self.pointCloud = map(lambda pnt: pnt + avgPointPos, self.pointCloud)
		self.t = np.zeros(3)
		self.R = np.identity(3)
		self.frameSize = frameSize
		self.focus = focus
	def read(self):
		pnts = np.array(self.projectPoints())
		frame = np.zeros(self.frameSize + (3,))

		for pnt in pnts.astype(int):
			if pnt[0] > 0 and pnt[1] > 1 and pnt[0] < self.frameSize[0] and pnt[1] < self.frameSize[1]:,tuple(pnt),5,[0,0,255],-1)
		return frame
	def addVecToPoint(self,points,vec):
		return map(lambda pnt: pnt + vec, points)
	def transformPoints(self):
		rotated =, self.R.T)
		translated = self.addVecToPoint(rotated, self.t)
		return translated
	def projectPoints(self):
		transformed = self.transformPoints()
		inFrontofCameraPoints = filter(lambda pnt: pnt[2] > 0, transformed)
		return map(lambda pnt: self.focus * pnt[:2]/pnt[2] + np.array(self.frameSize)/2, inFrontofCameraPoints)

cam = MyCam()
frame =
k = cv2.waitKey(0)

angle = .1

rotateZ = np.array([[np.cos(angle), np.sin(angle), 0],
					[-np.sin(angle), np.cos(angle), 0],
	frame =
	cam.R =, cam.R)
	k = cv2.waitKey(30) & 0xff
	if k == 27:

rotateX = np.array([[np.cos(angle), np.sin(angle), 0],
					[-np.sin(angle), np.cos(angle), 0],


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