Image information encoding and decoding method
摘要
說明書
Referring to Table 14, sao_type_cr_idx indicates an offset type of a chroma (Cr) signal. sao_type_cb_idx indicates an offset type of a chroma (Cb) signal. sao_cr_offset indicates an offset value of a chroma (Cr) signal. sao_cb_offset indicates an offset value of a chroma (Cb) signal.
In the example shown in Table 14, when the offset type to be applied to the chroma (Cr) signals is indicated by sao_type_cr_idx, the offset value indicated by sao_cr_offset may be applied to the current pixel. When the offset type to be applied to the chroma (Cb) signals is indicated by sao_type_cb_idx, the offset value indicated by sao_cb_offset may be applied to the current pixel.
On the other hand, additional information may be reduced while maintaining performance of the chroma offset in consideration of the characteristic difference between chroma and luma. For example, a chroma signal is smaller in edge component and simpler than a luma signal.
Therefore, by setting two categories for the edge offsets without setting four categories as in case of luma, it is possible to reduce the additional information. For example, in the edge offset table shown in Table 1, Category 1 and Category 3 may be merged into a single category and Category 2 and Category 4 may be merged into a single category. By merging the categories, it is possible to reduce the amount of offset value data to be transmitted when the edge offset is applied.
Table 15 schematically shows an example of edge offset categories to be applied to chroma pixels.
