获取OpenCV中RotatedRect的绝对角度

static double calcLineDegree(const Point2f& firstPt, const Point2f& secondPt)
{
double curLineAngle = 0.0f;
if (secondPt.x - firstPt.x != 0)
{
curLineAngle = atan(static_cast<double>(firstPt.y - secondPt.y) / static_cast<double>(secondPt.x - firstPt.x));
if (curLineAngle < 0)
{
curLineAngle += CV_PI;
}
}
else
{
curLineAngle = CV_PI / 2.0f; //90度
}
return curLineAngle*180.0f/CV_PI;
}
static double getRcDegree(const RotatedRect box)
{
double degree = 0.0f;
Point2f vertVect[4];
box.points(vertVect);
//line 1
const double firstLineLen = (vertVect[1].x - vertVect[0].x)*(vertVect[1].x - vertVect[0].x) +
(vertVect[1].y - vertVect[0].y)*(vertVect[1].y - vertVect[0].y);
//line 2
const double secondLineLen = (vertVect[2].x - vertVect[1].x)*(vertVect[2].x - vertVect[1].x) +
(vertVect[2].y - vertVect[1].y)*(vertVect[2].y - vertVect[1].y);
if (firstLineLen > secondLineLen)
{
degree = calcLineDegree(vertVect[0], vertVect[1]);
}
else
{
degree = calcLineDegree(vertVect[2], vertVect[1]);
}
return degree;
}