Question

我有多个OpenCV Videocapture来源，并且希望将其分别加载到不同的线程中。现在，图像和电影的加载很好，但是网络摄像头却给了我空的图像。仅当我在线程中执行此操作时才会发生这种情况。在我使用相同代码而没有线程的情况下，我从网络摄像头接收图像。 OpenCV给我以下错误：

[ERROR:0] VIDEOIO(makePtr<VideoCapture_DShow>(index)): raised unknown C++ exception!

有人可以帮我解决这个问题吗？

class render(threading.Thread):

    def __init__ (self, _scene):
        threading.Thread.__init__(self)
        self.scene = _scene

    def renderWebcam(self,src):
        camera = cv2.VideoCapture(src+cv2.CAP_DSHOW)
        camera.set(cv2.CAP_PROP_FRAME_WIDTH,1280)
        camera.set(cv2.CAP_PROP_FRAME_HEIGHT,720)

        while True:
            try:
                rc,image = camera.read()
                img = cv2.resize(image,(640,360))
                cv2.imwrite('renderfiles/Totaal.png', img)
                crop = image[100:460, 100:740]
                img = cv2.resize(crop,(640,360))
                cv2.imwrite('renderfiles/Ingezoomd.png', img)
            except KeyboardInterrupt:
                break;
        camera.release();
        cv2.destroyAllWindows()

我在Windows 10和Logitech网络摄像头上使用python 2.7

更新：发生此错误的最小设置是：

from threading import Thread
import cv2

def renderWebcam(src,name):
    camera = cv2.VideoCapture(src+cv2.CAP_DSHOW)

    while True:
        try:
            rc,image = camera.read()
            img = cv2.resize(image,(640,360))
            cv2.imwrite('renderfiles/'+name+'.png', img)
        except KeyboardInterrupt:
            break;
    camera.release();
    cv2.destroyAllWindows()

thread = Thread(target=renderWebcam, args=(0,'Webcam1')) 
thread.start()
thread = Thread(target=renderWebcam, args=(1,'Webcam2')) 
thread.start()

如何解决OpenCV错误捕获线程图像？

0 个答案: