Hi,
Officially TAO user guide is expecting customer to run with GitHub - NVIDIA-AI-IOT/deepstream_tao_apps: Sample apps to demonstrate how to deploy models trained with TAO on DeepStream 1
We do not know/verify when using deepstream-python-apps repo.
For using USB camera with deepstream-python-apps, could you search in deepstream forum or ask the question directly in deepstream forum (DeepStream SDK - NVIDIA Developer Forums)? I believe there are similar topics there.
For example,
https://forums.developer.nvidia.com/search?q=%22usb%20camera%22%20%20%20%23intelligent-video-analytics%3Adeepstream-sdk%20%20order%3Alatest
→ Deepstream 6.01 - Python app error - USB Camera ,
Deepstream4.0 TLT, How to run the application with USB video source - #2