一种用以更新转换系数准位之熵编码/译码所用之参数的方法。使用参数以将表示转换系数准位的语法元素进行二元化。将先前转换系数的尺寸与预定临界值做比较，且根据比较结果来更新或保留参数，其中预定临界值是基于先前转换系数准位语法元素实施反二元化时所用的先前参数而获得。预定临界值经设置以具有与先前参数成比例的值，当先前参数被更新时，更新后的参数相比先前参数而言具有逐步增大的值。

A method of updating a parameter used in entropy encoding and decoding of a transformation coefficient level. A syntax element indicating a transformation coefficient level is binarized by using a parameter. The parameter is renewed or maintained based on a result of comparing a size of a previous transformation coefficient with a predetermined critical value obtained based on a previous parameter used in de-binarization of a previous transformation coefficient level syntax element. The predetermined critical value is set to have a value proportional to the previous parameter, and when the previous parameter is renewed, the renewed parameter has a value that gradually increases compared to the previous parameter.