Spectral entropy-activity classification in adaptive transform coding
Rudolf Mester, Uwe Franke · IEEE Journal on Selected Areas in Communications · 1992
A two-dimensional feature space for block classification which discriminates reliably between blocks that require very different processing is proposed. In combination with a block 'activity' measurement, the introduced 'spectral entropy' feature offers the possibility to stabilize the reconstruction quality of transform coding systems for each processed block on a high level. The classification is valid and useful for threshold-based and zonal coding schemes.>