compare_coef ( : : RealCoef1, ImaginaryCoef1, RealCoef2, ImaginaryCoef2, MaxCoef, Damping : Distance )
Similarity of two contours.
The operator compare_coef calculates the Euclidean distance
between two contours which are available as Fourier coefficients.
In order to avoid that the higher frequencies are in some way
too dominant, the following attenuation can be used:
none No attenuation.
1/index Absolute amounts of the Fourier coefficients will be
divided by their index.
1/index*index] Absolute amounts of the Fourier coefficients will be
divided by their square index.
The higher the result value, the greater the differences between the
pattern and the test contour. If the number of coefficients is not
the same, only the first n coefficients will be compared.
The parameter MaxCoef indicates the number of the coefficients
to be compared. If MaxCoef is set to zero, all
coefficients will be used.
Parameters
RealCoef1 (input_control)
|
real-array -> real
|
Real parts of the pattern Fourier coefficients. |
ImaginaryCoef1 (input_control)
|
real-array -> real
|
Imaginary parts of the pattern Fourier coefficients. |
RealCoef2 (input_control)
|
real-array -> real
|
Real parts of the Fourier coefficients to be
compared. |
ImaginaryCoef2 (input_control)
|
real-array -> real
|
Imaginary parts of the Fourier coefficients to be
compared. |
MaxCoef (input_control)
|
integer -> integer
|
Total number of Fourier coefficients. |
Default value: 50 |
Suggested values: 0, 5, 10, 15, 20, 30, 40, 50, 70, 100, 200, 400 |
Restriction: MaxCoef >= 0 |
Damping (input_control)
|
string -> string
|
Kind of attenuation. |
Default value: ''1/index'' |
Suggested values: 'none', ''1/index'', ''1/index*index'' |
Distance (output_control)
|
real -> real
|
Similarity of the contours. |
Example
create_param_cont(trow,tcol,"unsigned_area",¶m_scale);
fourier_1dim(trow,tcol,param_scale,50,&frow,&fcol);
invariances(frow,fcol,1,"affine_invar",&invrow,&invcol);
absolute_invariant(invrow,invcol,1,2,"az_invar1",&absrow,&abscol);
compare_coef(contur1_row, contur1_col, contur2_row, contur2_col, 50,
"1/index", &Distance_wert);
Possible Predecessors
invariances
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