python - 如何使速度计算能够从两个方向（从上到下和从下到上）进行计算？

Question

我目前正在使用 Haar-cascade 进行人类步行速度估计的项目。该程序是这样工作的：检测到的物体通过两条假想线，当它通过第二条线时，程序将显示速度。我目前工作的程序只计算检测到的从上到下的物体，但我希望程序也能捕捉到从下到上的计算，这样它就可以双向计算。

这是程序：

import cv2
import time

cascade_src = 'haarcascade_fullbody.xml'
video_src = 'video-1.mp4'

#line a
ax1=15
ay=225
ax2=600

#line b
bx1=15
by=275
bx2=600

#car num
i = 1
start_time = time.time()

#video ....
cap = cv2.VideoCapture(video_src)
human_cascade = cv2.CascadeClassifier(cascade_src)   

videoWidth = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
videoHeight = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))

fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('wisuda-14.mp4', fourcc, 25.0, (videoWidth,videoHeight))

def Speed_Cal(time):
    try:
        Speed = (9.144*3600)/(time*1000)
        return Speed
    except ZeroDivisionError:
        print (5)

while True:
    ret, img = cap.read()
    if (type(img) == type(None)):
        break
    
    #bluring to have exacter detection
    blurred = cv2.blur(img, ksize=(3,3))
    gray = cv2.cvtColor(blurred, cv2.COLOR_BGR2GRAY)
    human = human_cascade.detectMultiScale(gray, scaleFactor=1.04865, minNeighbors=6)
    
    #line a #i know road has got 
    cv2.line(img,(ax1,ay),(ax2,ay),(255,0,0),2)
    #line b
    cv2.line(img,(bx1,by),(bx2,by),(255,0,0),2)
    
    for (x,y,w,h) in human:
        cv2.rectangle(img, (x,y), (x + w, y + h), (0, 0, 255), 2)
        roi_blurred = blurred[x: x + h, y:y + w]
        roi_gray = gray[x: x + h, y:y + w]
        roi_img = img[x: x + h, y:y + w]
        cv2.circle(img,(int((x+x+w)/2),int((y+y+h)/2)), 2,(0,255,0), -1)
        #cv2.putText(img, "ID : " + str(i), (x, y-15), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 0, 0), 1);
        
        while int(ay) == int((y+y+h)/2):
            start_time = time.time()
            break
            
        while int(ay) <= int((y+y+h)/2):
            if int(by) <= int((y+y+h)/2)&int(by+10) >= int((y+y+h)/2):
                cv2.line(img, (bx1,by), (bx2,by), (0,255,0), 2)
                Speed = Speed_Cal(time.time() - start_time)
                print("ID Number "+str(i)+" Speed: " + str(int(Speed)))
                i = i + 1
                cv2.putText(img, "Speed: "+str(int(Speed))+"km/jam", (x,y), cv2.FONT_HERSHEY_SIMPLEX, 1, (255,0,0), 2);
                break
            else :        
                break
                
                
    out.write(img)
    cv2.imshow('video', img)
    cv2.imshow('Gray', gray)
    cv2.imshow('Blurr', blurred)
    
    if cv2.waitKey(33) == 27:
        break

cap.release()
out.release()
cv2.destroyAllWindows()

希望你能帮助小伙伴们

标签： pythonopencvimage-processingvideo-processing