# Video composition use cases
Source: [https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html](https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html)
The video composition GStreamer use cases show how to read the video streams from the
source, compose them, and then display them either side by side or picture-in-picture on a
display device.
Before you run the use cases, ensure that you complete the preconditions mentioned in
[GStreamer command-line use cases](https://docs.qualcomm.com/doc/80-70022-50/topic/gstreamer-application-use-cases.html).
## 16 480p offline stream side by side composition
Source: [https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html](https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html)
The use case shows how to read 16 480p video streams from file sources and composing
them side by side. These streams are then displayed as a single frame on a local display
device.
Run the use case on the target
device:
ulimit -n 4096 && gst-launch-1.0 qtivcomposer name=mix sink_0::position="<0, 0>" sink_0::dimensions="<480, 270>" sink_1::position="<480, 0>" sink_1::dimensions="<480, 270>" sink_2::position="<960, 0>" sink_2::dimensions="<480, 270>" sink_3::position="<1440, 0>" sink_3::dimensions="<480, 270>" sink_4::position="<0, 270>" sink_4::dimensions="<480, 270>" sink_5::position="<480, 270>" sink_5::dimensions="<480, 270>" sink_6::position="<960, 270>" sink_6::dimensions="<480, 270>" sink_7::position="<1440, 270>" sink_7::dimensions="<480, 270>" sink_8::position="<0, 540>" sink_8::dimensions="<480, 270>" sink_9::position="<480, 540>" sink_9::dimensions="<480, 270>" sink_10::position="<960, 540>" sink_10::dimensions="<480, 270>" sink_11::position="<1440, 540>" sink_11::dimensions="<480, 270>" sink_12::position="<0, 810>" sink_12::dimensions="<480, 270>" sink_13::position="<480, 810>" sink_13::dimensions="<480, 270>" sink_14::position="<960, 810>" sink_14::dimensions="<480, 270>" sink_15::position="<1440, 810>" sink_15::dimensions="<480, 270>" mix. ! queue ! waylandsink sync=true fullscreen=true filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! queue ! mix.Copy to clipboard
To stop the use case, use CTRL + C.
Figure : Pipeline for side by side display of 16 480p video streams–file sources
## 1080p + 1080p offline picture-in-picture composition
Source: [https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html](https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html)
This use case shows the composition of two 1080p streams to get a picture-in-picture
display. The two 1080p streams are read from two file sources.
Run the use case on the target
device:
gst-launch-1.0 -e qtivcomposer name=mixer sink_0::position="<0, 0>" sink_0::dimensions="<1280, 720>" sink_1::position="<590, 310>" sink_1::dimensions="<640, 360>" mixer. ! queue ! waylandsink fullscreen=true filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! mixer. filesrc location=/tmp/Animals_000_720p_180s_30FPS.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! mixer. Copy to clipboard
To stop the use case, use CTRL + C.
Figure : Pipeline for picture-in-picture display of 1080p streams–file source
## 1080p live camera and 1080p offline picture-in-picture composition
Source: [https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html](https://docs.qualcomm.com/doc/80-70022-50/topic/video-composition.html)
The use case shows the composition of two 1080p streams to get a picture-in-picture
display. The first 1080p stream is read from a file source. The second stream is collected
from a camera.
Run the use case on the target device:
gst-launch-1.0 -e qtivcomposer name=mixer sink_0::position="<0, 0>" sink_0::dimensions="<1280, 720>" sink_1::position="<590, 310>" sink_1::dimensions="<640, 360>" mixer. ! queue ! waylandsink fullscreen=true qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! mixer. filesrc location=/opt/<1080p_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw, format=NV12 ! mixer.Copy to clipboard
To stop the use case, use CTRL + C.
Figure : Pipeline for picture-in-picture display of 1080p streams–file source and camera
source
### Related information
[Video composition](https://docs.qualcomm.com/doc/80-70022-50/topic/gst-weston-composition-example.html)
Last Published: Feb 20, 2026
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