Nvbuf_utils: Could not get EGL display connection (ZED2)

Software Python
1

Hello there,
I am using with Jetson nano in handless mode through VNC (Xorg). I have ZED camera plunged into the nano and trying to get live feed through VNC to another computer, the problem is when I run the ZED explorer (launcher for the ZED camera) it gives me bellow error

  • nvbuf_utils: Could not get EGL display connection
  • No EGL Display
  • nvbufsurftransform: Could not get EGL display connection

I have reffered similar topic but can’t solve.

***Environment

  • Jet pack : R32 (release), REVISION: 7.6, GCID: 38171779, BOARD: t210ref, EABI: aarch64, DATE: Tue Nov 5 07:46:14 UTC 2024
  • Kernel : Linux jetson-desktop 4.9.337-tegra
  • Hardware model : NVIDIA Jetson Nano Developer Kit
  • Ubuntu : 18.04.6 LTS
  • CUDA : 10.2.300
  • cuDNN : 8.2.1
  • TensorRT : 8.2.1
  • Gstreamer : 1.14.5
  • opencv(python) : 4.11.0
  • ZED sdk : 4.2.3
  • ZED pythonAPI (pyzed) : 4.2
    *Other setup : ```
    sudo apt install xrdp
    sudo apt install xfce4 xfce4-goodies
    echo xfce4-session > ~/.xsession

**xrandr
Screen 0: minimum 256 x 256, current 1920 x 1080, maximum 16384 x 16384
rdp0 connected 1920x1080+0+0 0mm x 0mm
1920x1080 50.00

xclock and xeyes can be gotten through VNC.
After that I try to do ZED pythonAPI (pyzed) but get above errors.

Next I try these command.
$ sudo jetson_clocks
$ gst-launch-1.0 v4l2src device=/dev/video1 ! video/x-raw,forma=YUY2,width=1280,height=480,framerate=30/1 ! nvvidconv ! ‘video/x-raw(memory:NVMM),format=NV12’ ! nvoverlaysink

But the results are bellow.
nvbuf_utils: Could not get EGL display connection
Setting pipeline to PAUSED …
Pipeline is live and does not need PREROLL …
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data stream error.
Additional debug info:
gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming stopped, reason not-negotiated (-4)
ERROR: pipeline doesn’t want to preroll.
Setting pipeline to PAUSED …
Setting pipeline to READY …
Setting pipeline to NULL …
Freeing pipeline …

What’s the reason?
Any ideas how to fix this issue?
Thank you.

2

Hi @moheji_ko
welcome to the Stereolabs community.

You must use a dummy HDMI/DisplayPort plug inserted in the screen connector to simulate the presence of a monitor.

The reasons are explained on this support page.

3

Thank you for your reply.
Could you tell me how to setup a dummy plug?
I got the plug (for HDMI, Evanlak) but that did not solve the problem.

4

I recommend installing NoMachine instead of using VNC

5

Thank you, I will try it.
Before that, I want to confirm two things.

  1. Jetson nano does not recognize dummy plug (for HDMI, Evanlak).
    Is thre any setup (command) for jetson nano?
  2. Just to be sure, what is the proper zed sdk version for jetson nano?
    (My environment has shown above.)
6

They normally work with Jetson Nano. Have you checked they are not broken?

You can use the latest version if the installed Jetpack (L4T) version is supported

7

Thank you for reply.

Yes. I use some plugs. But Jetson nano does not recognize.
With “dmesg | grep -i hdmi” command, plug-unplug action is recognized like bellow.

[ 1530.180363] Extcon AUX1(HDMI) disable
[ 1530.211294] tegradc tegradc.0: hdmi: tmds rate:83500K prod-setting:prod_c_hdmi_75m_150m
[ 1530.212313] tegradc tegradc.0: hdmi: get YCC quant from EDID.
[ 1530.247196] Extcon AUX1(HDMI) enable

But with “xrandr” command, HDMI screen is not recognized like bellow.

xrandr
Screen 0: minimum 256 x 256, current 1920 x 1080, maximum 16384 x 16384
rdp0 connected 1920x1080+0+0 0mm x 0mm
   1920x1080     50.00*

The version is JetPack 4.6.4 (L4T 32.7.6). How about that?

8

This seems a problem with the old Jetpack version.
I advise you search and eventually ask for a solution to the NVIDIA Developer Forum where you can get in direct contact with NVIDIA’s engineers.