VALUE
new_object(CvArr *arr, int is_binary = 0)
{
VALUE object = rb_allocate(rb_class());
cvMoments(arr, CVMOMENTS(object), is_binary);
return object;
}
/*
* call-seq:
* gravity_center -> cvpoint2d32f
*
* Return gravity center.
*/
VALUE
rb_gravity_center(VALUE self)
{
CvMoments *moments = CVMOMENTS(self);
double
m00 = cvGetSpatialMoment(moments, 0, 0),
m10 = cvGetSpatialMoment(moments, 1, 0),
m01 = cvGetSpatialMoment(moments, 0, 1);
return cCvPoint2D32f::new_object(cvPoint2D32f(m10 / m00, m01 / m00));
}
/*
* call-seq:
* CvHuMoments.new(<i>src_moments</i>)
*
* Calculates the seven Hu invariants.
* <i>src_moments</i> The input moments
*
* seven Hu invariants that are defined as:
* h1=η20+η02
* h2=(η20-η02)²+4η11²
* h3=(η30-3η12)²+ (3η21-η03)²
* h4=(η30+η12)²+ (η21+η03)²
* h5=(η30-3η12)(η30+η12)[(η30+η12)²-3(η21+η03)²]+(3η21-η03)(η21+η03)[3(η30+η12)²-(η21+η03)²]
* h6=(η20-η02)[(η30+η12)²- (η21+η03)²]+4η11(η30+η12)(η21+η03)
* h7=(3η21-η03)(η21+η03)[3(η30+η12)²-(η21+η03)²]-(η30-3η12)(η21+η03)[3(η30+η12)²-(η21+η03)²]
* where ηi,j are normalized central moments of 2-nd and 3-rd orders. The computed values are proved to be invariant to the image scaling, rotation, and reflection except the seventh one, whose sign is changed by reflection.
*/
VALUE
rb_initialize(VALUE self, VALUE src_moments)
{
try {
cvGetHuMoments(CVMOMENTS(src_moments), CVHUMOMENTS(self));
}
catch (cv::Exception& e) {
raise_cverror(e);
}
return self;
}
/*
* call-seq:
* CvMoments.new(<i>src[,is_binary = nil]</i>)
*
* Calculates all moments up to third order of a polygon or rasterized shape.
* <i>src</i> should be CvMat or CvPolygon.
*
* If is_binary = true, all the zero pixel values are treated as zeroes, all the others are treated as 1's.
*/
VALUE
rb_initialize(int argc, VALUE *argv, VALUE self)
{
VALUE src, is_binary;
rb_scan_args(argc, argv, "02", &src, &is_binary);
if (!NIL_P(src)) {
if (rb_obj_is_kind_of(src, cCvMat::rb_class()) || rb_obj_is_kind_of(src, cCvSeq::rb_class()))
cvMoments(CVARR(src), CVMOMENTS(self), TRUE_OR_FALSE(is_binary, 0));
else
rb_raise(rb_eTypeError, "argument 1 (src) should be %s or %s.",
rb_class2name(cCvMat::rb_class()), rb_class2name(cCvSeq::rb_class()));
}
return self;
}
/*
* call-seq:
* angle -> float
*
* Return angle.
*/
VALUE
rb_angle(VALUE self)
{
CvMoments *moments = CVMOMENTS(self);
double
m11 = cvGetCentralMoment(moments, 1, 1),
m20 = cvGetCentralMoment(moments, 2, 0),
m02 = cvGetCentralMoment(moments, 0, 2),
mangle = 0.5 * atan(2 * m11 / (m20 - m02));
if(cvIsNaN(mangle) || cvIsInf(mangle))
return Qnil;
else
return rb_float_new(mangle);
}
/*
* call-seq:
* hu -> cvhumoments
*
* Calculates seven Hu invariants.
*
* seven Hu invariants that are defined as:
* h1=η20+η02
* h2=(η20-η02)²+4η11²
* h3=(η30-3η12)²+ (3η21-η03)²
* h4=(η30+η12)²+ (η21+η03)²
* h5=(η30-3η12)(η30+η12)[(η30+η12)²-3(η21+η03)²]+(3η21-η03)(η21+η03)[3(η30+η12)²-(η21+η03)²]
* h6=(η20-η02)[(η30+η12)²- (η21+η03)²]+4η11(η30+η12)(η21+η03)
* h7=(3η21-η03)(η21+η03)[3(η30+η12)²-(η21+η03)²]-(η30-3η12)(η21+η03)[3(η30+η12)²-(η21+η03)²]
* where ηi,j are normalized central moments of 2-nd and 3-rd orders. The computed values are proved to be invariant to the image scaling, rotation, and reflection except the seventh one, whose sign is changed by reflection.
*/
VALUE
rb_hu(VALUE self)
{
return cCvHuMoments::new_object(CVMOMENTS(self));
}
/*
* call-seq:
* normalized_central -> float
*
* Retrieves normalized central moment.
*
* ηx_order,y_order= μx_order,y_order/M00((y_order+x_order)/2+1)
*/
VALUE
rb_normalized_central(VALUE self, VALUE x_order, VALUE y_order)
{
return rb_float_new(cvGetNormalizedCentralMoment(CVMOMENTS(self), NUM2INT(x_order), NUM2INT(y_order)));
}
/*
* call-seq:
* spatial -> float
*
* Retrieves spatial moment.
*
* which in case of image moments is defined as:
* Mx_order,y_order=sumx,y(I(x,y)*xx_order*yy_order)
* where I(x,y) is the intensity of the pixel (x, y).
*/
VALUE
rb_spatial(VALUE self, VALUE x_order, VALUE y_order)
{
return rb_float_new(cvGetSpatialMoment(CVMOMENTS(self), NUM2INT(x_order), NUM2INT(y_order)));
}
