The present invention, in one embodiment, is comprised of a method of performing region-of-interest editing of a video stream in the compressed domain. Inner and outer seal rings are provided to prevent leakage of the high-pressure fluid from the backpressure chamber. The collecting carrier is immovably connected to the object carrier of the automatic sun-tracking machine, and the object carrier is connected to the automatic sun-tracking machine. The gas bubble is formed at both sides of the heater.