Question about the Time warping implementation

[helloyide]

In paper: "A random point along the horizontal line passing through the center of the image within the time steps (W, τ − W ) is to be warped either to the left or right by a distance w chosen from a uniform distribution from 0 to the time warp parameter W along that line."

I checked the tensorflow implementation, it just move to right:
w = np.random.uniform(low=0, high=time_warping_para)
control_point_destination = [[center_position, random_point + w]]

Should I change it to
w = np.random.uniform(low=-time_warping_para, high=time_warping_para)
So the move could be in two directions?

Thanks