A method for decoding of a video bitstream implemented by a decoding device, wherein the video bitstream includes data representing an image region and an image region header of the image region, the video bitstream further comprises data representing a parameter set of the video bitstream, characterized in that the decoding method comprises: obtaining an override enabled flag from the parameter set of the video bitstream, wherein the parameter set is a sequence parameter set, SPS; when the value of the override enabled flag is an enabling value, obtaining an override flag from the image region header of the video bitstream, wherein the override flag indicates whether first partition constraint information from the image region header or second partition constraint information from the parameter set is to be used for partitioning a block of the image region, wherein the first partition constraint information comprises information of a minimum allowed quadtree leaf node size, information of a maximum multi-type tree depth, information of a maximum allowed ternary tree root node size or information of a maximum allowed binary tree root node size, and wherein the second partition constraint information comprises information of the minimum allowed quadtree leaf node size, information of the maximum multi-type tree depth, information of the maximum allowed ternary tree root node size or information of the maximum allowed binary tree root node size; when the value of the override flag is an overriding value, obtaining the first partition constraint information for the image region from the image region header; and partitioning the block of the image region according to the first partition constraint information; when the value of the override enabled flag is a disabling value, partitioning the block of the image region according to the second partition constraint information from the parameter set. obtaining an override enabled flag from the parameter set of the video bitstream, wherein the parameter set is a sequence parameter set, SPS; when the value of the override enabled flag is an enabling value, obtaining an override flag from the image region header of the video bitstream, wherein the override flag indicates whether first partition constraint information from the image region header or second partition constraint information from the parameter set is to be used for partitioning a block of the image region, wherein the first partition constraint information comprises information of a minimum allowed quadtree leaf node size, information of a maximum multi-type tree depth, information of a maximum allowed ternary tree root node size or information of a maximum allowed binary tree root node size, and wherein the second partition constraint information comprises information of the minimum allowed quadtree leaf node size, information of the maximum multi-type tree depth, information of the maximum allowed ternary tree root node size or information of the maximum allowed binary tree root node size; when the value of the override flag is an overriding value, obtaining the first partition constraint information for the image region from the image region header; and partitioning the block of the image region according to the first partition constraint information; when the value of the override flag is an overriding value, obtaining the first partition constraint information for the image region from the image region header; and partitioning the block of the image region according to the first partition constraint information; when the value of the override enabled flag is a disabling value, partitioning the block of the image region according to the second partition constraint information from the parameter set.