def extract_t0(data, img_len):
	""" Extract timestamp (t0) captured by Zenoh's Consumer """
	to_p1_idx = img_len + 2
	to_p2_idx = img_len + 3

	t0 = "{}.{}".format(
		data[to_p1_idx][0],
		data[to_p2_idx][0],
	)
	return float(t0)