Image Processing Reference
In-Depth Information
8.7 Summary
This chapter has considered a range of issues that arise in the practical implementa-
tion of the techniques described earlier in the topic. The first part concerned enve-
lope filters, which are a useful technique for reducing the rare gross errors that can
occur in certain types of filters. The remainder of the chapter has been concerned
with hardware implementation. No matter how well the methods work, they will
not be widely adopted if there are serious problems with implementation.
While the techniques appear to map to hardware in a straightforward way, they
do not in general scale well. Small increases in window size and bit depth can cause
very rapid increases in the hardware required making it impractical in some situa-
tions. A number of smarter methods for implementation including bit-serial ap-
proaches and bit-vector architecture have been presented that result in efficient
implementations.
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