首页>
外国专利>
Parameter update procedure for decoding entropy of the conversion coefficient level, and entropy decoding device of the conversion coefficient level using the same
Parameter update procedure for decoding entropy of the conversion coefficient level, and entropy decoding device of the conversion coefficient level using the same
展开▼
机译：用于解码转换系数等级的熵的参数更新过程，以及使用该参数更新过程的转换系数等级的熵解码设备
展开▼
页面导航
摘要
著录项
相似文献
摘要
A method for updating a parameter for its desbinarization when a transformation coefficient level syntax element is decoded by entropy, the procedure comprising: obtaining a binary string corresponding to a transformation coefficient level syntax element indicating a size of transformation coefficient included in a transformation unit, from a sequence of bits, in which the binary string includes a binary string of prefixes that is binarized using a truncated unary binarization and a binary string of suffixes that is binarized using binarization of exponential Golomb of order k-th; determine whether to update a previous parameter by comparing a size of a previous transformation coefficient that is restored before a current transformation coefficient, with a predetermined critical value obtained based on the previous parameter used in the desbinarization of a coefficient level syntax element of previous transformation indicating the size of the previous transformation coefficient, the previous parameter being used to determine a maximum value of a binary string of prefixes from a binary chain corresponding to a syntax element of the previous transformation coefficient level; obtain a current parameter used in the desbinarization of a current transformation coefficient level syntax element indicating a size of the current transformation coefficient by updating or maintaining the previous parameter based on a result of the determination, using the current parameter to determine a maximum value of a binary string of prefixes from a binary string corresponding to the current transformation coefficient level syntax element; and obtain the size of the current transformation coefficient by unbining the current transformation coefficient level syntax element using the current parameter obtained, in which obtaining the current parameter further comprises: when the value of the previous transformation coefficient is equal or more smaller than the predetermined critical value, it is determined that the current parameter is the previous parameter, and when the value of the previous transformation coefficient is larger than the predetermined critical value, it is determined that the current parameter is an updated value, in which the default critical value is set to have a value proportional to the previous parameter, and when the previous parameter is updated, the updated parameter has a value obtained by adding one to the previous parameter, and in which, when the size of the transformation coefficient is called absCoeff, a syntax element that indicates whether the c The transformation coefficient has a value greater than 1 is called coeff_abs_level_greater1_flag, and a syntax element that indicates whether the transformation coefficient has a value greater than 2 is called coeff_abs_level_greather2_flag, and when a basic level value is called baseLevel determined according with the equation: baseLevel = 1 + coeff_abs_level_greather1_flag + coeff_abs_level_greather2_flag, the transformation coefficient level syntax element indicates a size (absCoeff - baseLevel) that is a difference between the size of the determined absCoeff transformation coefficient and the basic level value baseLevel, in which, in determining whether to update the previous parameter, when the previous parameter is called cLastRiceParam, the same critical value is obtained based on the equation: th 3 * (1 cLastRiceParam), where " "indicates a left shift operator bit by bit and in which the p Current binarization parameter has a value equal to or smaller than a predetermined threshold value that has a value of 4.
展开▼
