| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a variable length decoder corresponding to a variable length encoding method that improves encoding efficiency in encoding a coefficient value. <P>SOLUTION: The variable length decoder includes: an arithmetic decoding means for arithmetically decoding code sequences from a high frequency component to a low frequency component in a predetermined order while switching a plurality of probability tables to be used for decoding; and a converting means for converting an absolute value of the coefficient value obtained by arithmetic decoding by the arithmetic decoding means into a coefficient value of a two-dimensional sequence in a block. In the arithmetic decoding means, the switching of the plurality of probability tables is one direction in which in arithmetically decoding the absolute value of a coefficient value subsequent to a coefficient value to be initially decoded after switching a new probability table, a probability table which has been used before the new probability table is not used again. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
