obtaining division information from a bitstream for an image;

dividing a first block included in the image into a plurality of second blocks based on the division information; and

reconstructing each of the second blocks,

wherein the first block is divided into the plurality of second blocks based on tree-based partitioning and type-based partitioning,

wherein the tree-based partitioning is performed recursively to divide a target block based on at least one of a quad tree division, a binary tree division or a triple tree division,

wherein the quad tree division refers to a division type of dividing the target block into four subblocks, the binary tree division refers to a division type of dividing the target block into two subblocks, and the triple tree division refers to a division type of dividing the target block into three subblocks,

wherein the type-based partitioning comprises

determining whether to perform the type-based partitioning on the target block based on a size of the target block;

obtaining, in case the type-based partitioning is determined to be performed, an index indicating a partitioning type for the target block; and

partitioning the target block based on the obtained index,

wherein the partitioning type of the type-based partitioning comprises a partitioning type where the target block is divided into four second blocks by three horizontal divisional lines or three vertical divisional lines,

wherein the type-based partitioning is performed once.