使用OpenCV打开MJPEG流失败

我想读一个像这样的本地流

try
{
    cv::utils::logging::setLogLevel(cv::utils::logging::LOG_LEVEL_VERBOSE);

    cv::VideoCapture vc;
    vc.setExceptionMode(true);
    vc.open("http://localhost:5010/TabletContent/Mjpeg", cv::CAP_OPENCV_MJPEG);

    std::vector<cv::VideoCapture> streams{ vc };
    std::vector<int> readyIndex;

    cv::Mat frame;
    while (cv::VideoCapture::waitAny(streams, readyIndex))
    {
        vc.retrieve(frame);
    }

}
catch (const std::exception& ex)
{
    std::cout << "\n" << ex.what();
}

[DEBUG:0] global C:\build\master_winpack-build-win64-vc15\opencv\modules\videoio\src\videoio_registry.cpp (165) cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Builtin backends(7): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940)
[DEBUG:0] global C:\build\master_winpack-build-win64-vc15\opencv\modules\videoio\src\videoio_registry.cpp (189) cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Available backends(7): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940)
[ INFO:0] global C:\build\master_winpack-build-win64-vc15\opencv\modules\videoio\src\videoio_registry.cpp (191) cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Enabled backends(7, sorted by priority): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940)
OpenCV(4.4.0) Error: Unspecified error (could not open 'http://localhost:5010/TabletContent/Mjpeg') in cv::VideoCapture::open, file C:\build\master_winpack-build-win64-vc15\opencv\modules\videoio\src\cap.cpp, line 177

OpenCV(4.4.0) C:\build\master_winpack-build-win64-vc15\opencv\modules\videoio\src\cap.cpp:177: error: (-2:Unspecified error) could not open 'http://localhost:5010/TabletContent/Mjpeg' in function 'cv::VideoCapture::open'