Capture camera by UDP

1

I stream the camera from another device by UDP, when I use a .sdp file with such content:

m=video 5000 RTP/AVP 96
c=IN IP4 224.1.1.1
a=rtpmap:96 H264/90000

I successfully receive my stream in VLC, but I would like to receive it by OpenCV.
I tried using VideoCapture(“udp://224.1.1.1:5000”, cv::CAP_FFMPEG) on my PC but I get :

[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\videoio_registry.cpp (197) cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Enabled backends(8, sorted by priority): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940); UEYE(930)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (396) cv::impl::getPluginCandidates Found 3 plugin(s) for FFMPEG
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_ffmpeg451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_ffmpeg451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_ffmpeg451_64.dll => OK
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (245) cv::impl::PluginBackend::PluginBackend Video I/O: initialized 'FFmpeg OpenCV Video I/O plugin': built with OpenCV 4.5 (ABI/API = 0/0), current OpenCV version is '4.5.1' (ABI/API = 0/1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (256) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: plugin is supported, but there is API version mismath: plugin API level (0) != OpenCV API level (1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (259) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: some functionality may be unavailable due to lack of support by plugin implementation
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (262) cv::impl::PluginBackend::PluginBackend Video I/O: plugin is ready to use 'FFmpeg OpenCV Video I/O plugin'
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (396) cv::impl::getPluginCandidates Found 2 plugin(s) for GSTREAMER
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_gstreamer451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_gstreamer451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (396) cv::impl::getPluginCandidates Found 2 plugin(s) for INTEL_MFX
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_intel_mfx451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_intel_mfx451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (396) cv::impl::getPluginCandidates Found 2 plugin(s) for MSMF
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_msmf451_64d.dll => OK
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (245) cv::impl::PluginBackend::PluginBackend Video I/O: initialized 'Microsoft Media Foundation OpenCV Video I/O plugin': built with OpenCV 4.5 (ABI/API = 0/0), current OpenCV version is '4.5.1' (ABI/API = 0/1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (256) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: plugin is supported, but there is API version mismath: plugin API level (0) != OpenCV API level (1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (259) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: some functionality may be unavailable due to lack of support by plugin implementation
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (262) cv::impl::PluginBackend::PluginBackend Video I/O: plugin is ready to use 'Microsoft Media Foundation OpenCV Video I/O plugin'
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\cap_images.cpp (282) cv::icvExtractPattern Pattern: udp://%03d.1.1.1:5000 @ 224
[ INFO:1] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (181) cv::impl::DynamicLib::libraryRelease unload H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_msmf451_64d.dll
[ INFO:2] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (181) cv::impl::DynamicLib::libraryRelease unload opencv_videoio_ffmpeg451_64.dll

I installed FFmpeg on my PC.

I don’t know how to do that, any idea?

2

Hi,

In which folder A is opencv_videoio_ffmpeg451_64d.dll?

Is A in Path variable?

3

I do can’t find “opencv_videoio_ffmpeg451_64d.dll” in my opencv dir (I downloaded it from the official site) I looked around my openCv folder but there’s no sign of it - am I doing something wrong? I only have “opencv_videoio_ffmpeg451_64.dll” in /bin. I copied that .dll to the compilation folder before.

Now I added it as a Path variable and my application doesn’t stop as before but I still get no image.

[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\videoio_registry.cpp (197) cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Enabled backends(8, sorted by priority): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940); UEYE(930)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (396) cv::impl::getPluginCandidates Found 3 plugin(s) for FFMPEG
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load H:\Moje\Pulpit\Praca\Git\TestProjects\OpenCVTest\opencv_videoio_ffmpeg451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_ffmpeg451_64d.dll => FAILED
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (175) cv::impl::DynamicLib::libraryLoad load opencv_videoio_ffmpeg451_64.dll => OK
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (245) cv::impl::PluginBackend::PluginBackend Video I/O: initialized 'FFmpeg OpenCV Video I/O plugin': built with OpenCV 4.5 (ABI/API = 0/0), current OpenCV version is '4.5.1' (ABI/API = 0/1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (256) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: plugin is supported, but there is API version mismath: plugin API level (0) != OpenCV API level (1)
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (259) cv::impl::PluginBackend::PluginBackend Video I/O: NOTE: some functionality may be unavailable due to lack of support by plugin implementation
[ INFO:0] global C:\build\master_winpack-build-win64-vc14\opencv\modules\videoio\src\backend_plugin.cpp (262) cv::impl::PluginBackend::PluginBackend Video I/O: plugin is ready to use 'FFmpeg OpenCV Video I/O plugin'
4

Hello, I was receiving the same INFO 0 messages in my code. I did not change any library from place, the error was in my code only, nevertheless the message still appearing, I guess these messages are only information about the process not error.

5

I noticed that I compile in Debug mode - in which it surely look for …d.dll (that I could not find). After compiling as Release I get no errors from the library. Only “.isOpened” returns false for me now.

So I still can’t receive my camera stream in OpenCV - in VLC it’s working. Am I passing something wrong? After all, VLC has that whole .sdp, maybe I need to give it something more parameters?

6

Is there no solution?

9

maybe ffmpeg can’t handle udp streams, maybe it can, I don’t know, I didn’t check, but it’s a possibility.

build with gstreamer. that might be able to handle your stream.