A hair extension holder including a main body and a cover. Power measurements for a neighboring cell can be scheduled during one or more frames not intended for power measurements. An encoding method may include encoding an input bit stream to generate first bit streams of C-bits, and receiving the first bit streams and shuffling data of the received first bit streams to generate second bit streams. The rotary inertial body, the rotary-body driving-force transmitting mechanism, and the rotary-inertial-body driving-force transmitting mechanism are provided coaxially with a rotary shaft of the rotary body. For example, by designating the resolution or size of an input digital image and determining the number of levels of the sub band encoding according to thus designated resolution or size, the decoding can be easily achieved to provide an image which is not much different in resolution or in size.