void mvContours::get_hu_moments (CvSeq* contour1, HU_MOMENTS &hu_moments) {
CvMoments moments;
double hus[7];
cvContourMoments(contour1, &moments);
cvGetHuMoments(&moments, (CvHuMoments*)hus);
hu_moments = std::vector<double>(hus, hus+sizeof(hus)/sizeof(double));
}
/*
* 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;
}
static int hu_moments_test( void )
{
const double success_error_level = 1e-7;
CvSize size = { 512, 512 };
int i;
IplImage* img = atsCreateImage( size.width, size.height, 8, 1, 0 );
CvMoments moments;
CvHuMoments a, b;
AtsRandState rng_state;
int seed = atsGetSeed();
double nu20, nu02, nu11, nu30, nu21, nu12, nu03;
double err = 0;
char buffer[100];
atsRandInit( &rng_state, 0, 255, seed );
atsbRand8u( &rng_state, (uchar*)(img->imageData), size.width * size.height );
cvMoments( img, &moments, 0 );
atsReleaseImage( img );
nu20 = cvGetNormalizedCentralMoment( &moments, 2, 0 );
nu11 = cvGetNormalizedCentralMoment( &moments, 1, 1 );
nu02 = cvGetNormalizedCentralMoment( &moments, 0, 2 );
nu30 = cvGetNormalizedCentralMoment( &moments, 3, 0 );
nu21 = cvGetNormalizedCentralMoment( &moments, 2, 1 );
nu12 = cvGetNormalizedCentralMoment( &moments, 1, 2 );
nu03 = cvGetNormalizedCentralMoment( &moments, 0, 3 );
cvGetHuMoments( &moments, &a );
b.hu1 = nu20 + nu02;
b.hu2 = sqr(nu20 - nu02) + 4*sqr(nu11);
b.hu3 = sqr(nu30 - 3*nu12) + sqr(3*nu21 - nu03);
b.hu4 = sqr(nu30 + nu12) + sqr(nu21 + nu03);
b.hu5 = (nu30 - 3*nu12)*(nu30 + nu12)*(sqr(nu30 + nu12) - 3*sqr(nu21 + nu03)) +
(3*nu21 - nu03)*(nu21 + nu03)*(3*sqr(nu30 + nu12) - sqr(nu21 + nu03));
b.hu6 = (nu20 - nu02)*(sqr(nu30 + nu12) - sqr(nu21 + nu03)) +
4*nu11*(nu30 + nu12)*(nu21 + nu03);
b.hu7 = (3*nu21 - nu03)*(nu30 + nu12)*(sqr(nu30 + nu12) - 3*sqr(nu21 + nu03)) +
(3*nu12 - nu30)*(nu21 + nu03)*(3*sqr(nu30 + nu12) - sqr(nu21 + nu03));
for( i = 0; i < 7; i++ )
{
double t = rel_err( ((double*)&b)[i], ((double*)&a)[i] );
if( t > err ) err = t;
}
sprintf( buffer, "Accuracy: %.4e", err );
return trsResult( err > success_error_level ? TRS_FAIL : TRS_OK, buffer );
}
VALUE
new_object(CvMoments *src_moments)
{
VALUE object = rb_allocate(rb_klass);
try {
cvGetHuMoments(src_moments, CVHUMOMENTS(object));
}
catch (cv::Exception& e) {
raise_cverror(e);
}
return object;
}
void mvHuMoments(IplImage *src, double *hus){
CvMoments moments;
cvMoments(src, &moments, true);
cvGetHuMoments(&moments, (CvHuMoments*)hus);
}
/*F///////////////////////////////////////////////////////////////////////////////////////
// Name: cvMatchContours
// Purpose:
// Calculates matching of the two contours
// Context:
// Parameters:
// contour_1 - pointer to the first input contour object.
// contour_2 - pointer to the second input contour object.
// method - method for the matching calculation
// (now CV_IPPI_CONTOURS_MATCH_I1, CV_CONTOURS_MATCH_I2 or
// CV_CONTOURS_MATCH_I3 only )
// rezult - output calculated measure
//
//F*/
CV_IMPL double
cvMatchShapes( const void* contour1, const void* contour2,
int method, double /*parameter*/ )
{
CvMoments moments;
CvHuMoments huMoments;
double ma[7], mb[7];
int i, sma, smb;
double eps = 1.e-5;
double mmm;
double result = 0;
if( !contour1 || !contour2 )
CV_Error( CV_StsNullPtr, "" );
// calculate moments of the first shape
cvMoments( contour1, &moments );
cvGetHuMoments( &moments, &huMoments );
ma[0] = huMoments.hu1;
ma[1] = huMoments.hu2;
ma[2] = huMoments.hu3;
ma[3] = huMoments.hu4;
ma[4] = huMoments.hu5;
ma[5] = huMoments.hu6;
ma[6] = huMoments.hu7;
// calculate moments of the second shape
cvMoments( contour2, &moments );
cvGetHuMoments( &moments, &huMoments );
mb[0] = huMoments.hu1;
mb[1] = huMoments.hu2;
mb[2] = huMoments.hu3;
mb[3] = huMoments.hu4;
mb[4] = huMoments.hu5;
mb[5] = huMoments.hu6;
mb[6] = huMoments.hu7;
switch (method)
{
case 1:
{
for( i = 0; i < 7; i++ )
{
double ama = fabs( ma[i] );
double amb = fabs( mb[i] );
if( ma[i] > 0 )
sma = 1;
else if( ma[i] < 0 )
sma = -1;
else
sma = 0;
if( mb[i] > 0 )
smb = 1;
else if( mb[i] < 0 )
smb = -1;
else
smb = 0;
if( ama > eps && amb > eps )
{
ama = 1. / (sma * log10( ama ));
amb = 1. / (smb * log10( amb ));
result += fabs( -ama + amb );
}
}
break;
}
case 2:
{
for( i = 0; i < 7; i++ )
{
double ama = fabs( ma[i] );
double amb = fabs( mb[i] );
if( ma[i] > 0 )
sma = 1;
else if( ma[i] < 0 )
sma = -1;
else
sma = 0;
if( mb[i] > 0 )
smb = 1;
else if( mb[i] < 0 )
smb = -1;
else
smb = 0;
if( ama > eps && amb > eps )
{
ama = sma * log10( ama );
amb = smb * log10( amb );
result += fabs( -ama + amb );
}
}
break;
}
case 3:
{
for( i = 0; i < 7; i++ )
{
double ama = fabs( ma[i] );
double amb = fabs( mb[i] );
if( ma[i] > 0 )
sma = 1;
else if( ma[i] < 0 )
sma = -1;
else
sma = 0;
if( mb[i] > 0 )
smb = 1;
else if( mb[i] < 0 )
smb = -1;
else
smb = 0;
if( ama > eps && amb > eps )
{
ama = sma * log10( ama );
amb = smb * log10( amb );
mmm = fabs( (ama - amb) / ama );
if( result < mmm )
result = mmm;
}
}
break;
}
default:
CV_Error( CV_StsBadArg, "Unknown comparison method" );
}
return result;
}
