1. An apparatus, comprising: a video encoder for encoding picture data for a block in a picture, wherein one or more tree structures are used to encode a binary set of data for indicating coefficient significance for the block, the one or more tree structures, comprising one or more sub-trees, each having a plurality of nodes, wherein, a set of sub-trees is used to encode a particular part of a significance map, said significance map indicating coefficient significance for the block, wherein each sub-tree is a data structure used to convey a particular significance map for a set of scanned coefficients, the coefficient significance is mapped to nodes of the tree structures, linked to neighboring coefficients from two dimensions, and wherein some nodes of the tree structures are processed to encode non-zeros, while other nodes of the tree structures are processed to encode zeros, and a flag indicates at least one significant coefficient in said block corresponding to the significance map.