Effective wedgelet partition coding using spatial prediction

An encoder for encoding a sample array into a data stream configured to:

• predict a first block of the sample array using intra-prediction by copying values of already encoded samples of the sample array, neighboring the first block, along an intra-prediction direction into the first block;
• derive a position of a wedgelet separation line within a second block of the sample array neighboring the first block based on an extension direction of the wedgelet separation line within the second block, wherein the extension direction is based on the intra-prediction direction used to predict the first block, and the wedgelet separation line divides the second block into first and second wedgelet partitions;
• and
• encode the second block based on a first value related to samples within the first wedgelet partition and a second value related to samples within the second wedgelet partition.

A non-transitory computer readable medium including a computer program comprising a program code for performing, when running on a computer, a method for reconstructing a sample array from a data stream, the method comprising:

• predicting a first block of the sample array using intra-prediction by copying reconstructed values of samples of the sample array, neighboring the first block, along an intra-prediction direction into the first block;
• deriving a position of a wedgelet separation line within a second block of the sample array neighboring the first block based on an extension direction of the wedgelet separation line within the second block, wherein the extension direction is based on the intra-prediction direction used to predict the first block, and the wedgelet separation line divides the second block into first and second wedgelet partitions;
• and
• decoding the second block based on a first value related to samples within the first wedgelet partition and a second value related to samples within the second wedgelet partition.