Question

我正在使用树莓派3 B型运行USB相机，并使用我正在使用的代码，它将不会在Pi上显示gif /相机显示。我正在寻找有关为什么可能无法正确显示的帮助。我正在使用Pi，将其插入带有USB键盘，鼠标和摄像头的显示器中。我希望代码对对象（人）进行计数并在它们停留在相机显示屏上设置的极限线内时对其进行计数。

我已经尝试了多个摄像头模块以及USB摄像头，但均无济于事。

import datetime
import math
import cv2
import numpy as np

import firebase

from firebase.firebase import FirebaseApplication

width = 0
height = 0
EntranceCounter = 0
ExitCounter = 0
min_area = 3000  # Adjust ths value according to your usage
_threshold = 70  # Adjust ths value according to your usage
OffsetRefLines = 150  # Adjust ths value according to your usage


# Check if an object in entering in monitored zone
def check_entrance_line_crossing(y, coor_y_entrance, coor_y_exit):
    abs_distance = abs(y - coor_y_entrance)

    if ((abs_distance <= 2) and (y < coor_y_exit)):
        return 1
    else:
        return 0


# Check if an object in exitting from monitored zone
def check_exit_line_crossing(y, coor_y_entrance, coor_y_exit):
    abs_distance = abs(y - coor_y_exit)

    if ((abs_distance <= 2) and (y > coor_y_entrance)):
        return 1
    else:
        return 0


camera = cv2.VideoCapture(0)

# force 640x480 webcam resolution
camera.set(3, 640)
camera.set(4, 480)

ReferenceFrame = None


# Frames may discard while adjusting to light
for i in range(0, 20):
    (grabbed, Frame) = camera.read()

    qtty_of_count = 0
while True:
    (grabbed, Frame) = camera.read()
    height = np.size(Frame, 0)
    width = np.size(Frame, 1)

    # if cannot grab a frame, this program ends here.
    if not grabbed:
        break

    # gray-scale and Gaussian blur filter applying
    GrayFrame = cv2.cvtColor(Frame, cv2.COLOR_BGR2GRAY)
    GrayFrame = cv2.GaussianBlur(GrayFrame, (21, 21), 0)

    if ReferenceFrame is None:
        ReferenceFrame = GrayFrame
        continue

    # Background subtraction and image manipulation
    FrameDelta = cv2.absdiff(ReferenceFrame, GrayFrame)
    FrameThresh = cv2.threshold(FrameDelta, _threshold, 255, cv2.THRESH_BINARY)[1]

    # Dilate image and find all the contours
    FrameThresh = cv2.dilate(FrameThresh, None, iterations=2)
    cnts, _ = cv2.findContours(FrameThresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)



    # plot reference lines (entrance and exit lines)
    coor_y_entrance = (height // 2) - OffsetRefLines
    coor_y_exit = (height // 2) + OffsetRefLines
    cv2.line(Frame, (0, coor_y_entrance), (width, coor_y_entrance), (255, 0, 0), 2)
    cv2.line(Frame, (0, coor_y_exit), (width, coor_y_exit), (0, 0, 255), 2)

    # check all found count
    for c in cnts:
        # if a contour has small area, it'll be ignored
        if cv2.contourArea(c) < min_area:
            continue

        qtty_of_count = qtty_of_count + 1
        app = FirebaseApplication('https://appproject-d5d51.firebaseio.com/', None)
        update = app.put('/car', "spaces", qtty_of_count)
        print("Updated value in FB value: " + str(update))
        (x, y, w, h) = cv2.boundingRect(c)
        cv2.rectangle(Frame, (x, y), (x + w, y + h), (0, 255, 0), 2)

        # find object's centroid
        coor_x_centroid = (x + x + w) // 2
        coor_y_centroid = (y + y + h) // 2
        ObjectCentroid = (coor_x_centroid, coor_y_centroid)
        cv2.circle(Frame, ObjectCentroid, 1, (0, 0, 0), 5)

        if (check_entrance_line_crossing(coor_y_centroid, coor_y_entrance, coor_y_exit)):
            EntranceCounter += 1

        if (check_exit_line_crossing(coor_y_centroid, coor_y_entrance, coor_y_exit)):
            ExitCounter += 1

print("Total countours found: " + str(qtty_of_count))

# Write entrance and exit counter values on frame and shows it
cv2.putText(Frame, "Entrances: {}".format(str(EntranceCounter)), (10, 50),
            cv2.FONT_HERSHEY_SIMPLEX, 0.5, (250, 0, 1), 2)
cv2.putText(Frame, "Exits: {}".format(str(ExitCounter)), (10, 70),
            cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255), 2)
cv2.imshow("Original Frame", Frame)
cv2.waitKey(1)

# cleanup the camera and close any open windows
camera.release()
cv2.destroyAllWindows()

我想显示摄像机并精确计数物体

运行代码时，使用USB摄像头没有摄像头显示出现

0 个答案: