FIELD: data processing.
SUBSTANCE: invention relates to the field of encoding / decoding video data. Video decoding device contains: a processor and a memory device storing executable instructions, which, when executed by the processor, induce it to: obtain a binary string corresponding to a level information of the current conversion coefficients by performing the arithmetic decoding of a bit stream; determine the current binary conversion parameter to determine a prefix binary string from mentioned binary string as one of (i) the previous binary conversion parameter and (ii) an updated value of the previous binary conversion parameter, obtained by adding n to the previous binary conversion parameter, based on a comparison between a predetermined value, which is proportional to the previous binary conversion parameter, and the value of the previous conversion coefficient; obtain the level information of the current conversion coefficient indicating the size of the conversion coefficient by cancelling a binary conversion of the binary value of the prefix binary string using a specific current binary conversion parameter, and determine the value of the current transform coefficient using the level information of the current conversion coefficient; and decode the data included in a conversion unit using inverse quantization and inverse conversion based on the value of the current conversion coefficient.
EFFECT: reducing the number of bits generated during encoding by varying the conversion parameter.
3 cl, 27 dwg, 2 tbl
