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Subband coding (SBC) has been a major technique in data
compression of speeches and images. Instead of conventional
rec- tangular bands in two dimensional subband coding of
images, a non-separable diamond-shaped frequency
decomposition which splits the original signal into four
uniform subbands along the diagonal directions is discussed
in this work. This diamond- shaped frequency decomposition
matches the human visual system more closely than the
conventional rectangular bands. The sub- band video coding
system proposed is built up based on this diamond-shaped
subband filtering system. One motivation of adopting subband
structures is that each subband can be coded by the optimal
coding algorithm according to its own characteristics. The
coding algorithms which are adaptive to the different
properties of the four subbands from diamond-shaped analysis
filter bank are discussed in this work. Subband coding system
is very suitable for the transmission of video or image in
the broadband ISDN for its hierarchical structure. In the
ATM network the priority scheme is used to provide the
basic service quality. An adaptive layered coding system which
is based on the diamond-shaped subband structure is proposed.
This adaptive scheme can provide a superior ability of cell
loss resilience. Some other processings which can reduce the
reconstruction errors introduced by cell loss or transmission
errors are also presented.
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