Hierarchical encoding and decoding apparatus for a digital image signal

摘要

In a hierarchical encoding apparatus, predictors each including a look-up table are used to form predicted signals for respective hierarchical levels. The difference between the predicted signal and the original signal forms the differential signal for the higher hierarchical levels. The look-up table contains either predictive coefficients which are used as weights for pixels of a signal in one hierarchical level to produce a signal at a higher hierarchical level, or representative values which are combined with a dynamic range and redundant component in a set of pixels of a signal in one hierarchical level to produce a signal at a higher hierarchical level. The values in the look-up table are obtained from representative images.