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Table 2. Interpretation rules for quarter-notes and sharps
Structural contexts before
recognition - Hand-drawn
strokes
Structural contexts after
recognition - Re-transcribed
symbols
Interpretation rules
FilledNoteHead
(Stroke s)
DCV:
Staff→staff[on,all]s.
SCV:
.
SR:
HeadNotes, {
FilledNoteHead }.
DCC:
this[left,all]Accidental
1
,
this[right,all]Dot
1
,
(this[rightUprising,all] UprisingStem
1
|
this[leftDescending,all] DescendingStem
1
).
Sharp
(HorizontalSegment hs1 , HorizontalSegment hs2,
VecticalSegment vs1 , VecticalSegment vs2)
DCV:
Head→head[left,all]hs1,
head[left,all]hs2,
head[left,all]vs1,
head[left,all]vs2.
SCV:
hs1[intersects]vs1,
hs1[intersects]vs2,
hs2[intersects]vs1,
hs2[intersects]vs2,
hs1[below,all]hs2,
vs1[right,all]vs2.
SR:
Accidentals, {Sharp}.
DCC: .
only the relevant recognizers, depending on the
context of an element. It is essential to increase
the interpretation process robustness, since the
less symbols a recognizer must interpret, the
more efficient and the more reliable it is. The SR
block syntax is:
For example, to interpret a sharp, we exploit
a recognizer able to recognize accidentals, and
we want its answer to be a sharp. This way, the
coupling of the global and the local visions model
that it is more pertinent to call an accidental rec-
ognizer than a stem recognizer or a dot recognizer
on elements located on the left of a note head. A
SR block modelling this can be written as:
SR: SymbolFamily , {AcceptedAnswers}.
This expression means that the recognizer of
SymbolFamily
is called, with the rule parameters
as input. If its answer is included in
{AcceptedAn-
swers}
the recognition process is a success. If no
{AcceptedAnswers}
is specified, then any answer
of the recognizer is acceptable. The order of the
elements presented to the recognizer is the order
of the parameters in the declaration of the rule;
so it is always the same. As a result, its work is
relieved, because it has to interpret the elements
always in the same order.
Stem
recognizer
SR: Accidentals ,
Accidental
recognizer
{Sharp}.
Dot
recognizer
Document Context Creation Block (DCC)
The document context creation block specifies
a list of document structural contexts which are
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