I am using this command: gst-launch-1.0 v4l2src ! xvimagesink
to stream video over usb on my nvidia jetson nano and I am getting this output:
Setting pipeline to PAUSED...
ERROR: Pipeline doesn't want to pause.
ERROR: from element /GstPipeline:pipeline0/GstXvImageSink:xvimagesink0: Could not initialise Xv output
Additional debug info:
xvimagesink.c(1773): gst_xv_image_sink_open (): /GstPipeline:pipeline0/GstXvImageSink:xvimagesink0:
Could not display (null)
Setting pipeline to NULL..
Freeing pipeline...
Related
I am creating a video stream from my headless raspberry pi using usb camera and opencv.
Ubuntu 18.04 LTS
Raspi OS: Bullseye
USB Camera
gst syntax test on terminal:
gst-launch-1.0 v4l2src device=/dev/video0 ! videoconvert! videoscale ! video/x-raw, width=640, height=480 ! autovideosink -v
In OpenCV C++:
string pipeline;
pipeline = "v4l2src device=/dev/video0 ! videoconvert! videoscale ! video/x-raw, width=640, height=480 ! autovideosink -v";
cv::VideoCapture cap(pipeline, cv::CAP_GSTREAMER);
When I launch the pipeline from terminal it creates a window with by usb webcam feed. However when I try to use the same pipeline from c++ it throws this error:
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (734) open OpenCV | GStreamer warning: Error opening bin: syntax error
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (501) isPipelinePlaying OpenCV | GStreamer warning: GStreamer: pipeline have not been created
terminate called after throwing an instance of 'std::invalid_argument'
what(): cannot predict with an empty OpenCV image
Aborted
What am i missing in the syntax in the code?
Edit:
After some trials I could get the pipeline generated, with this:
pipeline = "v4l2src device=/dev/video0 ! videoconvert! video/x-raw, width=640, height=480 ! appsink";
and warning:
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (961) open OpenCV | GStreamer warning: Cannot query video position: status=0, value=-1, duration=-1
.
.
.
some stuff for that frame
.
.
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (509) isPipelinePlaying OpenCV | GStreamer warning: unable to query pipeline state
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (1824) handleMessage OpenCV | GStreamer warning: Embedded video playback halted; module v4l2src0 reported: Could not read from resource.
When searched for it, I found this post. Which led to a bug report here and here.
I am using OpenCV 4.5, and I assume that bug would have been fixed by later version as it was reported for OpenCV 3.4.
when I am trying to send a video sample that I downloaded from the internet, which has both AAC and H-264 codecs the following command is working fine. but when I generated the mp4 file using OpenCV which has only the H-264 codec and no AAC as there was no audio it is giving me the following error.
command :
gst-launch-1.0 -v filesrc location="YourAudioVideo.mp4" ! qtdemux name=demux ! queue ! h264parse ! video/x-h264,stream-format=avc,alignment=au ! kvssink name=sink stream-name="audio-video-file" access-key="YourAccessKeyId" secret-key="YourSecretAccessKey" streaming-type=offline demux. ! queue ! aacparse ! sink.
error log :
Additional debug info:
./grammar.y(506): gst_parse_no_more_pads (): /GstPipeline:pipeline0/GstQTDemux:demux:
failed delayed linking some pad of GstQTDemux named demux to some pad of GstQueue named queue0
WARNING: from element /GstPipeline:pipeline0/GstQTDemux:demux: Delayed linking failed.
Additional debug info:
./grammar.y(506): gst_parse_no_more_pads (): /GstPipeline:pipeline0/GstQTDemux:demux:
failed delayed linking some pad of GstQTDemux named demux to some pad of GstQueue named queue1
ERROR: from element /GstPipeline:pipeline0/GstQTDemux:demux: Internal data stream error.
Additional debug info:
qtdemux.c(5850): gst_qtdemux_loop (): /GstPipeline:pipeline0/GstQTDemux:demux:
streaming stopped, reason not-linked (-1)
Execution ended after 0:00:00.005448416
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...
You obviously remove the AAC part in your pipeline then:
gst-launch-1.0 -v filesrc location="YourAudioVideo.mp4" ! qtdemux name=demux ! queue ! h264parse ! video/x-h264,stream-format=avc,alignment=au ! kvssink name=sink stream-name="audio-video-file" access-key="YourAccessKeyId" secret-key="YourSecretAccessKey" streaming-type=offline
Gstreamer playbin cannot play my IPCamera mjpeg rtsp with 2048x1534 resolution:
gst-launch-1.0 -v playbin uri=rtsp://admin:admin#192.168.1.100:554/1/1
It shows the following WARNING message:
WARNING: from element /GstPlayBin:playbin0/GstURIDecodeBin:uridecodebin0/GstDecodeBin:decodebin0/GstRtpJPEGDepay:rtpjpegdepay0: Invalid Dimension 0x1536.
I have also test the following pipeline to force video size:
gst-launch-1.0 -v rtspsrc location=rtsp://admin:admin#192.168.1.100:554/1/1 ! application/x-rtp,media="video",width=2048,height=1536 ! rtpjpegdepay ! jpegdec ! autovideosink
but it complains similar WARNING message.
It should be note that when I change my video encoding to H.264 from camera panel everything is OK with playbin!
I'm trying to open UDP stream video in Raspberry Pi using this pipeline:
VideoCapture video("udpsrc port=5600 ! application/x-rtp,payload=96,encoding-name=H264 !"
"rtpjitterbuffer mode=1 ! rtph264depay ! h264parse ! decodebin ! videoconvert ! appsink emit-signals=true sync=false max-buffers=2 drop=true", cv::CAP_GSTREAMER);
// Exit if video is not opened
if(!video.isOpened())
{
cout << "Could not read video file" << endl;
return 1;
}
However, video.isOpened() return false and I couldn't be able to open with this code. This works on loopback test and another Ubuntu 18.04 PC but RPi 4 (Buster OS) couldn't run it. Also following lines can run upcoming gstream video:
gst-launch-1.0 udpsrc port=5600 caps='application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264' ! rtph264depay ! h264parse ! avdec_h264 ! autovideosink fps-update-interval=1000 sync=false
Furthermore specific code stack (e.g. [video_udp.cpp][1]) can easily handle video but also it's hard to use with opencv.
NOTE: OpenCV version is 4.2.0-pre
The problem is about using GStreamer library as a plugin of OpenCV. OpenCV doesn't throw exception even you build source code without GStreamer support. (In default, GStreamer library was directly found by Ubuntu, conversely Raspberry Pi 4 couldn't find it.)
Firstly I check build information of OpenCV with std::cout<<cv::getBuildInformation(); in Ubuntu 18.04 machine and found that:
GStreamer: YES (1.14.5)
Also I just check this on Raspberry Pi 4 side and build information was:
GStreamer:NO
Before the build OpenCV I just compare GStreamer plugins with gst-inspect-1.0 command for both of them and I just install some missing plugins like gstreamer1.0-tools . Also I wasn't know the problem, before the checking build information, so I installed some other GStreamer plugins that currently I don't remember.
Lastly, I build system by adding -D WITH_GSTREAMER=ON flag. And now it works well.
I'll edit answer if the problem related to missing plugins those are installed later. For this, I'll check this issue with clean Buster OS image.
I'm trying to develop an application which should analyse a video stream from a MIPI camera(5MP). So I'm using gstreamer to get the video feed access it using OpenCV. I tried the following pipeline and it's working:
imxv4l2videosrc device="/dev/video0" ! autovideosink
But when I try to use it with OpenCV, it gives some errors.
VideoCapture cap("imxv4l2videosrc device=\"/dev/video0\" ! autovideosink");
OpenCV Error: Unspecified error (GStreamer: cannot find appsink in manual pipeline
) in cvCaptureFromCAM_GStreamer, file /root/OpenCV/opencv/modules/videoio/src/cap_gstreamer.cpp, line 759
VIDEOIO(cvCreateCapture_GStreamer (CV_CAP_GSTREAMER_FILE, filename)): raised OpenCV exception:
/root/OpenCV/opencv/modules/videoio/src/cap_gstreamer.cpp:759: error: (-2) GStreamer: cannot find appsink in manual pipeline
in function cvCaptureFromCAM_GStreamer
Then I tried to use the following pipeline, and it's not working as well:
VideoCapture cap("imxv4l2videosrc device=\"/dev/video0\" ! appsink");
ERROR: unrecognized std! 0 (PAL=ff, NTSC=b000
ERROR: v4l2 capture: unsupported ioctrl!
GStreamer Plugin: Embedded video playback halted; module imxv4l2videosrc0 reported: Internal data flow error.
ERROR: v4l2 capture: unsupported ioctrl!
OpenCV Error: Unspecified error (GStreamer: unable to start pipeline
) in cvCaptureFromCAM_GStreamer, file /root/OpenCV/opencv/modules/videoio/src/cap_gstreamer.cpp, line 832
VIDEOIO(cvCreateCapture_GStreamer (CV_CAP_GSTREAMER_FILE, filename)): raised OpenCV exception:
/root/OpenCV/opencv/modules/videoio/src/cap_gstreamer.cpp:832: error: (-2) GStreamer: unable to start pipeline
in function cvCaptureFromCAM_GStreamer
GStreamer version: 1.0
OpenCV version: 3.2
What is the piece i'm missing here?
Or is my approach is wrong?
Here is the answer to my question(with #Alper Kucukkomurler's help)
You can access the MIPI camera through OpenCV (with GStreamer) with
VideoCapture cap("imxv4l2videosrc device=\"/dev/video0\" ! videoconvert ! appsink");
Also If you want to change the resolution of the input, imx-capture-mode parameter can be used, which is of imxv4l2videosrc element.
For example,
imxv4l2videosrc imx-capture-mode=5 ! <other elements>