Methods, systems and devices for using flexible and efficient partitioning techniques are described. An exemplary method for visual media decoding includes applying, to a current visual media block, a partitioning process that splits the current visual media block into exactly four sub-blocks including at least one sub-block that has a size different from half of a width of the current visual media block times half of a height of the current visual media block, decoding, based on a bitstream representation, the four sub-blocks, and decoding, based on the four sub-blocks and the partitioning process, the current visual media block.