小编Moh*_*mar的帖子

这个代码块(在views.py中)由URL触发.导入cv2时没有问题.(使用virtualenvwrapper尝试的同样的事情显示相同的结果(添加所有必需的库之后)相机初始化和....

def caminit(request):  
  cam.open(0)
  img=cam.read()
  cv2.imwrite("snap"+".jpg",img[1])
  cam.release()                                #takes the instant pic

  faceCascade =cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
  eye_cascade = cv2.CascadeClassifier('haarcascade_eye.xml')

检查时 print type(faceCascade) 给出<type 'cv2.CascadeClassifier'>.对象已创建.

继续前进 caminit

image = cv2.imread("snap.jpg")

# when checked with image.dtype it shows correct uint8 also image.shape shows correct data {Eg: (480, 640, 3)}

gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# Detect faces in the image
faces = faceCascade.detectMultiScale(
    gray,
    scaleFactor=1.1,
    minNeighbors=5,
    minSize=(30, 30),
    flags = cv2.cv.CV_HAAR_SCALE_IMAGE
)

现在关键部分"寻找面孔的数量"

print "Found {0} faces!".format(len(faces))

终端输出:

Found 0 faces!

为什么会这样？ …

以下给出了下面提到的代码的错误.哪里出错了？

error: ‘function’ is not a member of ‘std’

我想使用C++ std lib队列进行优先级队列,最小化队列是IceCream,它花费的时间最少.我试过实现这个 - > 用自定义比较器在c ++中声明一个priority_queue

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <map>
#include <vector>
#include <queue>
#include <deque>
#include <iterator>
#include <string>
#include <sstream>

using namespace std;


class IceCream
{
 public:
   int time_to_prep;
    IceCream(int flav) {
          time_to_prep = flav;
       }
};

bool Compare(IceCream a, IceCream b)
{
    return a.time_to_prep > b.time_to_prep;
}

int main()
{
    priority_queue<IceCream, vector<IceCream>, std::function<bool(IceCream a, IceCream b)> > my_pq(Compare);
    my_pq.push(IceCream(4)); …