static void draw_line2( double *x, double *y, int num )
{
ARMat *input, *evec;
ARVec *ev, *mean;
double a, b, c;
int i;
ev = arVecAlloc( 2 );
mean = arVecAlloc( 2 );
evec = arMatrixAlloc( 2, 2 );
input = arMatrixAlloc( num, 2 );
for( i = 0; i < num; i++ ) {
arParamObserv2Ideal( dist_factor, x[i], y[i],
&(input->m[i*2+0]), &(input->m[i*2+1]) );
}
if( arMatrixPCA(input, evec, ev, mean) < 0 ) exit(0);
a = evec->m[1];
b = -evec->m[0];
c = -(a*mean->v[0] + b*mean->v[1]);
arMatrixFree( input );
arMatrixFree( evec );
arVecFree( mean );
arVecFree( ev );
draw_warp_line(a, b, c);
}
static int arGetLine2(int x_coord[], int y_coord[], int coord_num,
int vertex[], double line[4][3], double v[4][2], double *dist_factor)
{
ARMat *input, *evec;
ARVec *ev, *mean;
double w1;
int st, ed, n;
int i, j;
ev = arVecAlloc( 2 );
mean = arVecAlloc( 2 );
evec = arMatrixAlloc( 2, 2 );
for( i = 0; i < 4; i++ ) {
w1 = (double)(vertex[i+1]-vertex[i]+1) * 0.05 + 0.5;
st = (int)(vertex[i] + w1);
ed = (int)(vertex[i+1] - w1);
n = ed - st + 1;
input = arMatrixAlloc( n, 2 );
for( j = 0; j < n; j++ ) {
arParamObserv2Ideal( dist_factor, x_coord[st+j], y_coord[st+j],
&(input->m[j*2+0]), &(input->m[j*2+1]) );
}
if( arMatrixPCA(input, evec, ev, mean) < 0 ) {
arMatrixFree( input );
arMatrixFree( evec );
arVecFree( mean );
arVecFree( ev );
return(-1);
}
line[i][0] = evec->m[1];
line[i][1] = -evec->m[0];
line[i][2] = -(line[i][0]*mean->v[0] + line[i][1]*mean->v[1]);
arMatrixFree( input );
}
arMatrixFree( evec );
arVecFree( mean );
arVecFree( ev );
for( i = 0; i < 4; i++ ) {
w1 = line[(i+3)%4][0] * line[i][1] - line[i][0] * line[(i+3)%4][1];
if( w1 == 0.0 ) return(-1);
v[i][0] = ( line[(i+3)%4][1] * line[i][2]
- line[i][1] * line[(i+3)%4][2] ) / w1;
v[i][1] = ( line[i][0] * line[(i+3)%4][2]
- line[(i+3)%4][0] * line[i][2] ) / w1;
}
return(0);
}
static double check_error( double *x, double *y, int num, double dist_factor[4] )
{
ARMat *input, *evec;
ARVec *ev, *mean;
double a, b, c;
double error;
int i;
ev = arVecAlloc( 2 );
mean = arVecAlloc( 2 );
evec = arMatrixAlloc( 2, 2 );
input = arMatrixAlloc( num, 2 );
for( i = 0; i < num; i++ ) {
arParamObserv2Ideal( dist_factor, x[i], y[i],
&(input->m[i*2+0]), &(input->m[i*2+1]) );
}
if( arMatrixPCA(input, evec, ev, mean) < 0 ) exit(0);
a = evec->m[1];
b = -evec->m[0];
c = -(a*mean->v[0] + b*mean->v[1]);
error = 0.0;
for( i = 0; i < num; i++ ) {
error += (a*input->m[i*2+0] + b*input->m[i*2+1] + c)
* (a*input->m[i*2+0] + b*input->m[i*2+1] + c);
}
error /= (a*a + b*b);
arMatrixFree( input );
arMatrixFree( evec );
arVecFree( mean );
arVecFree( ev );
return error;
}