Hi,
Multiple use-cases are supported in deepstream-app, so certain plugins are used. And we can easily modify config file to run different use-cases.
There are posts about constructing pipelines through gst-launch-1.0 commands:
Adding a ghost pad after splitting a pipeline using Tee? - #11 by DaneLLL
Could not link nvarguscamerasrc0 to nvstreammux0 - #10 by DaneLLL
Writing a custom Gstreamer plugin - #3 by DaneLLL
Nvmultistreamtiler/nvstreamdemux with omxh264enc won't work - #5 by DaneLLL
You may refer to the pipelines and construct yours.