IMAGE DECODING METHOD, IMAGE CODING METHOD, IMAGE DECODING APPARATUS, IMAGE CODING APPARATUS, AND IMAGE CODING AND DECODING APPARATUS

An image includes a plurality of rows of largest coding units (LCUs). Encoding the image includes determining whether or not wavefront parallel processing is enabled, and partitioning the plurality of rows of LCUs to comprise a normal slice and a group of dependent slices. The normal slice includes at least one LCU, and the group of dependent slices includes at least one LCU and consists of every dependent slice that uses information from a slice header of the normal slice for encoding. Based on the determination that wavefront parallel processing is enabled, the partitioning of the plurality of rows of LCUs is restricted such that a last LCU in the group of dependent slices belongs in a same row as a first LCU of the normal slice when the first LCU of the normal slice is not a first LCU of the row.