# Gstreamer Compositor error

**URL:** <https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271>\
**Category:** Jetson Nano\
**Tags:** gstreamer\
**Created:** [November 9, 2022, 9:25am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271 "2022-11-09T09:25:51Z")\
**Posts on this page:** 9\
**Page:** 1

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**Author:** ![pulzappcheck890](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@pulzappcheck890](https://forums.developer.nvidia.com/u/pulzappcheck890)\
**Post date:** [November 9, 2022, 9:25am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/1 "2022-11-09T09:25:51Z")

</div>

Hi,

I’m trying to use compositor and when i try to run the pipeline it throws an error as below:

**WARNING: erroneous pipeline: could not link queue2 to comp**

The used pipeline as follows:

**gst-launch-1.0 -v v4l2src device=/dev/exCAM io-mode=2 ! tee name=t2 ! queue ! image/jpeg,width=1920,height=1080,framerate=30/1 ! videorate ! image/jpeg,width=1920,height=1080,framerate=30/1 ! nvv4l2decoder mjpeg=1 ! nvvidconv ! queue ! “video/x-raw(memory:NVMM),width=960,height=540,format=NV12”! identity ! queue ! comp.sink\_0 filesrc location=/home/ums4/Downloads/GST/eduscope-logo-.png ! image/png,width=1720 ,height=1440,framerate=0/1,pixel-aspect-ratio=1/1 ! pngdec ! videoconvert ! imagefreeze ! video/x-raw,framerate=30/1 ! nvvidconv ! ‘video/x-raw(memory:NVMM),width=1950,height=270,format=NV12,pixel-aspect-ratio=1/1’ ! identity ! queue ! comp.sink\_1 compositor name=comp sink\_0::xpos=0 sink\_0::ypos=0 sink\_0::width=320 sink\_0::height=240 sink\_1::xpos=0 sink\_1::ypos=240 sink\_1::width=320 sink\_1::height=240 ! video/x-raw,width=320,height=480 ! videoconvert ! xvimagesink**

Thanks in advance.

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<div class="post-metadata">

**Author:** ![pulzappcheck890](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@pulzappcheck890](https://forums.developer.nvidia.com/u/pulzappcheck890)\
**Post date:** [November 9, 2022, 10:17am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/2 "2022-11-09T10:17:03Z")

</div>

When i try to overlay an image over the video, it does not show the preview.

The used pipeline as follows:

**gst-launch-1.0 videotestsrc pattern=snow ! video/x-raw,width=1280,height=720,framerate=30/1 ! queue ! comp.sink\_0 gdkpixbufoverlay location=/home/ums4/Downloads/GST/eduscope-logo-.png offset-x=-1 offset-y=-1 overlay-width=40 overlay-height=40 ! videoconvert ! queue ! nvvidconv ! queue ! comp.sink\_1 compositor name=comp sink\_0::xpos=0 sink\_0::ypos=0 sink\_0::zorder=1 sink\_1::xpos=0 sink\_1::ypos=0 sink\_1::zorder=2 ! videoconvert ! xvimagesink**

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<div class="post-metadata">

**Author:** ![Honey\_Patouceul](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/honey_patouceul/32/389777_2.png) [@Honey\_Patouceul](https://forums.developer.nvidia.com/u/Honey_Patouceul)\
**Post date:** [November 9, 2022, 4:01pm UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/3 "2022-11-09T16:01:46Z")

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You have 2 issues:

- First one is that you are using nvvidconv that has at least one of its input or output in NVMM memory. For compositor, the inputs are expected to be in system memory.
- Second one is that gdkpixbufoverlay overlays the picture onto a video stream, but in your pipeline it has no input, so it never starts.  
You may try:

```auto
# With gdkpixbufoverlay:
gst-launch-1.0 videotestsrc pattern=snow ! video/x-raw,width=1280,height=720,framerate=30/1 ! gdkpixbufoverlay location=/usr/share/jetsonpowergui/logo/nv_logo.png offset-x=-1 offset-y=-1 overlay-width=272 overlay-height=203 ! videoconvert ! xvimagesink

# Or with compositor
gst-launch-1.0 \
videotestsrc pattern=snow ! video/x-raw,width=1280,height=720,framerate=30/1 ! queue ! comp.sink_0 \
filesrc location=/usr/share/jetsonpowergui/logo/nv_logo.png ! pngdec ! imagefreeze ! video/x-raw,framerate=30/1 ! videoconvert ! video/x-raw,format=RGBA ! queue ! comp.sink_1 \
compositor name=comp sink_0::width=1280 sink_0::height=720 sink_0::zorder=0 sink_1::xpos=1179 sink_1::ypos=619 sink_1::width=100 sink_1::height=100 sink_1::zorder=1 ! videoconvert ! xvimagesink

```

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<div class="post-metadata">

**Author:** ![pulzappcheck890](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@pulzappcheck890](https://forums.developer.nvidia.com/u/pulzappcheck890)\
**Post date:** [November 10, 2022, 5:04am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/4 "2022-11-10T05:04:17Z")

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Thank You. This was the exact output needed.

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<div class="post-metadata">

**Author:** ![pulzappcheck890](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@pulzappcheck890](https://forums.developer.nvidia.com/u/pulzappcheck890)\
**Post date:** [November 10, 2022, 11:31am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/5 "2022-11-10T11:31:31Z")

</div>

Hi,

i tried the above mentioned pipeline with **v4lsrc** and when i try to run the pipeline with a PNG image, the video feed seems to be lagging. The used p-line as follows:

**gst-launch-1.0 videotestsrc pattern=red ! video/x-raw,width=1280,height=720,framerate=30/1 ! queue ! comp.sink\_0 v4l2src device=/dev/exCAM io-mode=2 ! tee name=t2 ! queue ! image/jpeg,width=1920,height=1080,framerate=30/1 ! videorate ! image/jpeg,width=1920,height=1080,framerate=30/1 ! nvv4l2decoder mjpeg=1 ! nvvidconv ! queue ! “video/x-raw,width=960,height=540,format=NV12” ! queue ! queue ! comp.sink\_1 filesrc location=/home/usr/Downloads/GST/logo-.png ! pngdec ! imagefreeze ! video/x-raw,framerate=30/1 ! videoconvert ! comp.sink\_2 compositor name=comp sink\_0::width=1280 sink\_0::height=720 sink\_0::zorder=0 sink\_1::xpos=1179 sink\_1::ypos=619 sink\_1::width=100 sink\_1::height=100 sink\_1::zorder=2 sink\_2::xpos=179 sink\_2::ypos=619 sink\_2::width=500 sink\_2::height=100 sink\_2::zorder=1 ! videoconvert ! ximagesink**

Also, when i try to run without any image, the pipeline seems to be functioning with no lag. The p-line as follows:

**gst-launch-1.0 videotestsrc pattern=red ! video/x-raw,width=1280,height=720,framerate=30/1 ! queue ! comp.sink\_0 v4l2src device=/dev/exCAM io-mode=2 ! tee name=t2 ! queue ! image/jpeg,width=1920,height=1080,framerate=30/1 ! videorate ! image/jpeg,width=1920,height=1080,framerate=30/1 ! nvv4l2decoder mjpeg=1 ! nvvidconv ! queue ! “video/x-raw,width=960,height=540,format=NV12” ! queue ! queue ! comp.sink\_2 compositor name=comp sink\_0::width=1280 sink\_0::height=720 sink\_0::zorder=0 sink\_1::xpos=1179 sink\_1::ypos=619 sink\_1::width=100 sink\_1::height=100 sink\_1::zorder=2 sink\_2::xpos=179 sink\_2::ypos=619 sink\_2::width=500 sink\_2::height=100 sink\_2::zorder=1 ! videoconvert ! ximagesink**

How to eliminate this problem?

Thanks in advance.

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<div class="post-metadata">

**Author:** ![Honey\_Patouceul](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/honey_patouceul/32/389777_2.png) [@Honey\_Patouceul](https://forums.developer.nvidia.com/u/Honey_Patouceul)\
**Post date:** [November 10, 2022, 12:48pm UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/6 "2022-11-10T12:48:12Z")

</div>

You may enclose your code into code blocks starting and closing with a line having just : ```  
This would save many time when trying your case.

I don’t have a real V4L JPG camera, so I emulated one:

```auto
gst-launch-1.0 \
  videotestsrc ! video/x-raw,width=640,height=480,framerate=30/1 ! nvvidconv ! 'video/x-raw(memory:NVMM),format=I420' ! nvvidconv ! 'video/x-raw(memory:NVMM),width=1920,height=1080' ! nvjpegenc ! image/jpeg,width=1920,height=1080,framerate=30/1 ! tee name=jpgcam \
  videotestsrc pattern=red ! video/x-raw,width=1280,height=720,framerate=30/1,format=RGBA ! queue ! comp.sink_0 \
  jpgcam. ! queue ! image/jpeg,width=1920,height=1080,framerate=30/1 ! nvv4l2decoder mjpeg=1 ! nvvidconv ! 'video/x-raw,width=500,height=500,format=RGBA,pixel-aspect-ratio=1/1' ! queue ! comp.sink_1 \
  filesrc location=/usr/share/jetsonpowergui/logo/nv_logo.png ! pngdec ! imagefreeze ! video/x-raw,framerate=30/1 ! videoscale add-borders=0 ! 'video/x-raw,width=500,height=100,pixel-aspect-ratio=1/1' ! videoconvert ! video/x-raw,format=RGBA ! queue ! comp.sink_2 \
  compositor name=comp sink_0::width=1280 sink_0::height=720 sink_0::zorder=0 sink_1::xpos=1179 sink_1::ypos=619 sink_1::width=100 sink_1::height=100 sink_1::zorder=2 sink_2::xpos=179 sink_2::ypos=619 sink_2::width=500 sink_2::height=100 sink_2::zorder=1 ! videoconvert ! ximagesink -v

```

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<div class="post-metadata">

**Author:** ![pulzappcheck890](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@pulzappcheck890](https://forums.developer.nvidia.com/u/pulzappcheck890)\
**Post date:** [November 11, 2022, 6:07am UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/7 "2022-11-11T06:07:18Z")

</div>

The pipeline works by making the image transparent. But, when i try to make the webcam video size bigger,  
the frame-rate drops relatively. The P-line as follows:

**gst-launch-1.0 videotestsrc pattern=red ! video/x-raw,width=1280,height=720,framerate=30/1,format=RGBA ! queue ! comp.sink\_0 v4l2src device=/dev/exCAM io-mode=2 ! queue ! image/jpeg,width=1920,height=1080,framerate=30/1 ! nvv4l2decoder mjpeg=1 ! nvvidconv ! ‘video/x-raw,width=500,height=500,format=RGBA,pixel-aspect-ratio=1/1’ ! queue ! comp.sink\_1 filesrc location=/home/usr/Downloads/GST/-logo-.png ! pngdec ! imagefreeze ! video/x-raw,framerate=30/1 ! videoscale add-borders=0 ! ‘video/x-raw,width=500,height=100,pixel-aspect-ratio=1/1’ ! videoconvert ! video/x-raw,format=RGBA ! queue ! comp.sink\_2 compositor name=comp sink\_0::width=1280 sink\_0::height=720 sink\_0::zorder=0 sink\_1::xpos=79 sink\_1::ypos=19 sink\_1::width=970 sink\_1::height=540 sink\_1::zorder=2 sink\_2::xpos=179 sink\_2::ypos=19 sink\_2::width=500 sink\_2::height=100 sink\_2::zorder=2 ! videoconvert ! ximagesink -v**

How can we achieve this while using NVIDIA encoders to function without frame drop?

Thanks In advance

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<div class="post-metadata">

**Author:** ![Honey\_Patouceul](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/honey_patouceul/32/389777_2.png) [@Honey\_Patouceul](https://forums.developer.nvidia.com/u/Honey_Patouceul)\
**Post date:** [November 13, 2022, 9:22pm UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/8 "2022-11-13T21:22:36Z")

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> [@Honey\_Patouceul](#):
>
> You may enclose your code into code blocks starting and closing with a line having just : ```  
> This would save many time when trying your case.

Please help me to help you.  
Once this is ok, better create a new topic for this new issue.

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**Author:** ![system](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/system/32/68080_2.png) [@system](https://forums.developer.nvidia.com/u/system)\
**Post date:** [November 27, 2022, 9:22pm UTC](https://forums.developer.nvidia.com/t/gstreamer-compositor-error/233271/9 "2022-11-27T21:22:49Z")

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Closed on November 27, 2022, 9:22pm UTC

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