Encoding or decoding a video signal includes determining a first partitioning of at least a portion of a frame before a current frame in a video sequence. The first partitioning is modified to a second partitioning using a motion vector that predicts at least one prediction sub-region of a first region from the first partitioning. The second partitioning is used to encode or decode a current region of the current frame. The current region may be collocated with the first region. The technique eliminates the need to re-partition an entire frame each time, and can be used with both rectangular-shaped block partitioning and partitioning using masks and other partitioning techniques.