A scalable decoder system having a decoder reconstruction system, wherein the
decoder
reconstruction system comprises: an estimation algorithm
##EQU1##
for estimating a lost discrete cosine transform (DCT) coefficient, which incorporates
the quantization noise of previous enhancement layer data into the expectation,
wherein the estimation algorithm includes a density distribution dependent on at
least one unknown parameter {circumflex over ()}l; and a parameter
estimation algorithm for estimating {circumflex over ()}l according
to the equation:
##EQU2##
wherein bl denotes each of a set of quantizer decision levels
l, and {circumflex over (P)}l is the sum of a set of a normalized frequency
of occurrences of data quantized to each quantizer decision level 1,2, . . . , l.
