Download ridge counting and tracing

Ridge Counting
The process of counting the ridges that touch or
cross the line of count drawn between the delta
and core of loop patterns. A white space must
always intervene between the delta and the first
ridge to be counted.
Ridge Count
The number of ridges intervening between the
delta and core.
Rules in Ridge Counting
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Locate the exact points of the core and delta
Count all the ridges which touch or cross an
imaginary line drawn between the core and
delta
Never include the core and delta in counting.
Count only those ridges which intervene or pass
the imaginary line of count of line
Incipient ridges are never counted no matter
where they appear. The general rule is that in
order to be counted, the width of a ridge must
be equal to the width of the other ridges in the
pattern under consideration.
Ridges included in ridge counting
and their numerical value:
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An island ridge or dot ridge is given one ridge
count
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A short ridge is given one ridge count
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A long ridge is given one ridge count
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An abrupt ending ridge is given one count
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If a ridge bifurcates into two across the
imaginary line, the ridge count is two
If the point of origin of a bifurcating ridge is on
the line of count, the ridge count is two
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If the legs of enclosure or eyelet ridge is on the
line of count, the ridge count is two
If the intersection of two enclosures is on the
line of count, the ridge count is two
If the intersection of two enclosures is on the
line of count, then the ridge count is four
When the core is located on ending ridge which
touches the inside of the innermost re-curving
ridge, the recurve is included in counting only
when the delta is located below a line drawn at
right angle to the end or tip of such ending ridge
Ridge Counting in Whorl Patterns
Whorl patterns are counted only if they appear in
the little fingers of both hands. If there is no loop in
the eight fingers (little fingers not included), the
first whorl is to be counted to obtain the key
classification formula
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A plain whorl and central pocket loop are
treated as an ulnar loop
A double loop (twinned loop) is counted to an
upright loop
An accidental whorl is counted from the
extreme corresponding delta to the nearest core
(least number of ridge count)
The counting in a lateral loop is made between
the lower delta and the nearer loop regardless
of whether the print is found on the left or right
hand.
Ridge Tracing
The process of coursing or tracing the ridge that
originates from the left delta flowing towards the
right delta or near the point and determining the
number of intervening ridges between the traced
ridge and right delta to constitute the three
subdivisions such as inner, meeting and outer
presented by capital I, M, O.
Rules in Ridge Tracing
When the deltas have been located, the tracing
starts on the ridge emanating from the lower side
or point of the left delta until the point nearest or
opposite the right delta is reached. Then the
number of ridges intervening between the traced
ridge and the right delta are counted to determine
whether it is inner (I), meet or meeting (M) or outer
(O).
If the traced ridge ends without reaching the right
side, it is necessary to drop perpendicularly to a
point on a ridge directly below and continue the
tracing up to the relative point nearest the right
delta.
If the traced ridge is a bifurcation, follow the lower
branch and if this branch ends abruptly, drop on
the next ridge until tracing is completed.
Subdivisions of Whorls
According to Tracing
Inner Whorl (I)
If the traced ridge reached the relative point
nearest the right delta and goes above or inside
it and there are 3 or more intervening ridges
between the traced ridge and the right delta, it is
considered as an inner whorl.
Meet or Meeting Whorl (M)
A whorl pattern is considered meet or meeting if
the traced ridge reached the relative point nearest
the right delta and goes above/ inside; or below/
outside with 1 or 2 intervening ridges between
such delta and traced ridge, or if the traced ridge
started from the left delta and runs directly to
the right delta.
Outer Whorl (O)
A whorl pattern is considered outer if the traced
ridge reached the relative point near the right delta
and goes below or outside such delta with 3 or
more ridges intervening between such delta and
traced ridge.