1. A method of decoding video, the method comprising: obtaining bit strings corresponding to current transformation coefficient level information by arithmetic decoding a bitstream based on a context model; determining a current binarization parameter by updating or maintaining a previous binarization parameter based on a comparison of a predetermined value and a size of a previous transformation coefficient; obtaining the current transformation coefficient level information by performing de-binarization of the bit strings using the determined current binarization parameter; and generating a size of a current transformation coefficient using the current transformation coefficient level information.