Question

import numpy as np
import cv2 as cv
cap = cv.VideoCapture("walking")
kernel = cv.getStructuringElement(cv.MORPH_ELLIPSE,(3,3))
fgbg = cv.bgsegm.createBackgroundSubtractorGMG()
    while(1):
        ret, frame = cap.read()
        fgmask = fgbg.apply(frame)
        fgmask = cv.morphologyEx(fgmask, cv.MORPH_OPEN, kernel)
        im2, contours, hierarchy = cv.findContours(fgmask, cv.RETR_TREE, cv.CHAIN_APPROX_SIMPLE)
        cv.drawContours(fgmask, contours, -1, (0,255,0), 3)

    if len(contours) > 0:
        for count in contours:
            x,y,w,h = cv.boundingRect(count)
            cv.rectangle(fgmask,(x,y),(x+w,y+h),(0,255,0),2)

    cv.imshow('frame',fgmask)
    cv.imshow("stan",frame)
    k = cv.waitKey(30) & 0xff
    if k == 27:
        break
cap.release()
cv.destroyAllWindows()

这是我的代码，我试图在视频中围绕轮廓设置一个方框，在这种情况下是多个行人走路。根本没有盒子出现，我在某个地方犯了一个简单的错误吗？

Answer 1

缩进错误。检测到的轮廓的边界框的绘制以及显示结果不在while循环中。因此，您只是在阅读框架，查找这些框架的轮廓，但您没有在显示窗口上显示它们。当您在视频中阅读时，您需要对框架进行更新。

取while循环和后面的前5行并将其移至缩进级别0：

import numpy as np
import cv2 as cv
cap = cv.VideoCapture("walking")
kernel = cv.getStructuringElement(cv.MORPH_ELLIPSE,(3,3))
fgbg = cv.bgsegm.createBackgroundSubtractorGMG()

while(1):
    ret, frame = cap.read()
    fgmask = fgbg.apply(frame)
    fgmask = cv.morphologyEx(fgmask, cv.MORPH_OPEN, kernel)
    im2, contours, hierarchy = cv.findContours(fgmask, cv.RETR_TREE, cv.CHAIN_APPROX_SIMPLE)
    cv.drawContours(fgmask, contours, -1, (0,255,0), 

    if len(contours) > 0:
        for count in contours:
            x,y,w,h = cv.boundingRect(count)
            cv.rectangle(fgmask,(x,y),(x+w,y+h),(0,255,0),2)

    cv.imshow('frame',fgmask)
    cv.imshow("stan",frame)
    k = cv.waitKey(30) & 0xff
    if k == 27:
        break

cap.release()
cv.destroyAllWindows()

边界框没有显示在背景中使用opencv减去视频

1 个答案: