are very promising, taking into account that the tested
schemes are extremely simple. Only a fraction of
available information, i.e., the line/edge code with-
out amplitude and color information, and without a
linking of scales as explored in the segregation model,
has been used so far. More extensive tests are being
conducted, with more images and objects, concentrat-
ing on a linking of scales and a steering of attention
from coarse to fine scales. Such improved schemes
are expected to yield better results, from very fast de-
tection (where) to slower categorization (where/what)
to recognition (what). The balance between keypoint
and line/edge representations is an important aspect.
ACKNOWLEDGEMENTS
This research is partly financed by PRODEP III Me-
dida 5, Action 5.3, and by the FCT program POSI,
framework QCA III.
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