Recognition of facial expressions - Knowledge Based Systems ...

o call a specialized routine for computing the probability of existence of
current parameter being in current state, given the parent parameters
being in the states specified through the current combination
o fills in the data in the Conditional Probability Table (CPT) of the
current parameter
- saves the data on the disk, in a file having the same name as the input file. The
difference is that the saved model has the data in parameter CPTs.
In order to be able to query the program for obtaining the probability associated to a
certain state of the parameters, a C++ class tackles the data within the chosen
parametric model (Listing 9).
//---------------------------------------------------
1: class model
2: {
3: public:
4: file a[1000];
5: int n;
6: int NP; //no.of parameters
7: int NC; //no.of classes
8: public:
9: model():n(0){}
10: bool readDatabase(char*);
11: void show(void);
12: float computeP(cere&);
13: float computeP2(cere2&);
14: float computeP3(int,char*);
15: float computeP4(int,char*,bool);
16: int countExpression(char*);
17: bool isIncluded(FACS&,FACS&);
18: void select(query&,model&);
19: void emptyDatabase(void){n=0;}
20: int countFields(void){return n;}
21: int getClass(int,int);
22: void save(char*);
23: char* getFieldExpression(int);
24: private:
25: float compare(FACS&,FACS&);
26: void insertField(int,int,FACS&,char*);
27: };
//---------------------------------------------------
Listing 9. C++ class to handle the model data
The class is used to manage all the processing on the data and to store the data related to
the sample data from the initial sample database. An instance of the structure “file” stores
internally the Action Units sequence, the description of the facial emotion and the value
of the parameters. The definition is given in Listing 10.
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