A life vest includes a hydration pack capable of providing hydration to a user of the life vest; and a personal locator having a global positioning system receiver and a transmitter capable of transmitting the global positioning system location of the user of the life vest. The graphics processing pipeline includes a chroma downsampling unit for performing buffer-free downsampling of chroma pixel components. The novel sensors and flow controllers require only small amounts of electrical power for sensing users of bathroom facilities, and thus enable battery operation for many years.