Opencv中KeyPoint类中的默认构造函数如下:
CV_WRAP KeyPoint() : pt(0,0), size(0), angle(-1), response(0), octave(0), class_id(-1) {}
现分析各项属性
pt(x,y):关键点的点坐标;point2f类型;
size():该关键点邻域直径大小;
angle:角度,表示关键点的方向,值为[零,三百六十),负值表示不使用。
response:响应强度,网络上有如下解释:
1)”The response, by which the strongest keypoints have been selected.”
2)”Responseis indeed an indicator of “how good” (roughly speaking, in terms of corner-ness) a point is. The higher, the better. The strongest keypoints means the ones that are the best.“
octacv:从哪一层金字塔得到的此关键点。
class_id:当要对图片进行分类时,用class_id对每个关键点进行区分,默认为-1。