- ... convergence1
- In the case of active shape models, on the contrary, inspection of
nearby structures guided the model so that it better matched the target.
Since the model landmarks usually reflect on the location of strong
edges, similarity could be well-approximated by the distance between
model points and strongest edges in their vicinity. Search along normals
to the lines joining these landmarks led to appropriate edges location,
provided that initialisation placed the model close enough to the
target.
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- ...
images2
- This reverse process is used, for example, in application where reconstruction
of faces or generation of flexible faces is of some value. Real-time
animation is another possible extension of this.
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- ... analysis3
- Procrustes analysis has proved to be a popular method of shape analysis.
The generalized Procrustes procedure was developed by Gower (1975)
and has been adapted for shape analysis by Goodall (1991).
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- ... model4
- The model is constructed using only
examples where
is
the total number of examples and is then evaluated in accordance with
the single left-out example. This procedure is usually performed
times, with a different example put aside at each iteration and averaging
is then used to estimate the relevancy of the model.
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- ... folding5
- For closed curves, convex in particular, such problems are minute
yet not negligible. A monotonically increasing reparameterisation
function will ensure that points along the curve will at no stage
overlap or conflict with one another in some way. It also has the
advantage of allowing any number of landmarks to be considered, so
resolution constrained could be specified beforehand.
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- ... time6
- There has been the temptation of optimising several examples from
the set in a distributed manner.
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- ... slow7
- The algorithms currently used for demonstration purposes take 3 days
to run, but substantial speed-up is expected soon.
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- ... group-wise8
- Another advancement in current research is the inclusion of the whole
set of data rather than just a one-to-one (pairwise) correlation between
data and the current AAM. An investigation of just a couple at a time
leads to poorer results in later practical use. That are due to the
limited scope of the approach.
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- ... unprecedented9
- Comment: I am making some risky guesses here (as I often
did beforehand). Apologies for any disturbing assumptions
that I make to preserve good flow.
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