code: @Override
  	public void compute(float x, float y, Point2D_F32 out) {
  		float sum = 0;
  
  		float radial[] = params.radial;
  		float t1 = params.t1, t2 = params.t2;
  
  		// out is undistorted normalized image coordinate
  		out.x = a11*x + a12*y + a13;
  		out.y = a22*y + a23;
  
  		float r2 = out.x * out.x + out.y * out.y;
  		float ri2 = r2;
  
  		for (int i = 0; i < radial.length; i++) {
  			sum += radial[i] * ri2;
  			ri2 *= r2;
  		}
  
  		float tx = 2 * t1 * out.x * out.y + t2 * (r2 + 2 * out.x * out.x);
  		float ty = t1 * (r2 + 2 * out.y * out.y) + 2 * t2 * out.x * out.y;
  
  		// now compute the distorted normalized image coordinate
  		out.x = out.x*(1 + sum) + tx;
  		out.y = out.y*(1 + sum) + ty;
  	}
docs: Adds radial distortion
  
  @param x   Undistorted x-coordinate pixel
  @param y   Undistorted y-coordinate pixel
  @param out Distorted pixel coordinate.