1. A method of decoding video data hierarchically encoded as a set that has subsets with set symbols, the method comprising: receiving encoded data; and using the encoded data, reconstructing data values hierarchically encoded as a given set, including: evaluating a set symbol of the given set; selectively decoding a symbol combination code that indicates respective set symbols of plural subsets of the given set, including, when the set symbol of the given set is a first symbol element, skipping the decoding the symbol combination code, and otherwise performing the decoding the symbol combination code; assigning the respective set symbols of the plural subsets to the plural subsets of the given set; and for each of the plural subsets, selectively repeating the reconstructing when the subset has multiple data values, including, for a given subset of the plural subsets, evaluating the set symbol of the given subset, selectively decoding a symbol combination code that indicates respective set symbols of further subsets of the given subset, assigning the respective set symbols of the further subsets to the further subsets of the given subset, and, for each of the further subsets, selectively repeating the reconstructing for that further subset.