PARTITIONED INTRA CODING CONCEPT
Block-based coding of a picture is done by providing an intra-prediction coding concept according to which a certain block of the picture is intra-prediction coded using a certain intra-coding mode by partitioning the predetermined block into partitions which are, for reconstruction purposes, sequentially subject to spatial prediction using the intra-prediction coding mode signaled for the certain block followed by correcting the thus obtained predictor using a prediction residual so that for preceding partitions a reconstruction of the samples is available to the decoder at the time of processing the next, then current, partition.
1 . A method for decoding of a picture from a data stream, the method comprising:
decoding a split mode flag for a block of the picture from the data stream, wherein the block is a leaf block subdivided from a tree-root block using recursive multi-tree subdivision;
determining an intra-coding mode of the block;
in response to a determination that the split mode flag indicates a first split mode:
determining a number of partitions into which the block is partitioned, wherein a width of the partitions, measured along a partition dimension, is determined out of at least two different width settings using implicit signaling, and
sequentially reconstructing each partition of the block according to a partition order based on the intra-coding mode of the block; and
in response to a determination that the split mode flag indicates a second split mode, reconstructing the block using spatial intra prediction based on the intra-coding mode,
wherein using the spatial intra prediction for reconstructing the block, comprises:
further subdividing the block into leaf blocks of an hierarchical multi-tree subdivision of the block along horizontal and vertical subdivision leaf block borders, and
sequentially reconstructing the leaf blocks of the block according to a leaf block order which sequentially traverses the leaf blocks of the block.