Current gaze sample use the uridecodebin as the source, it does not support V4L2 interface camera. deepstream_tao_apps/apps/tao_others/deepstream-gaze-app/deepstream_gaze_app.cpp at release/tao5.3_ds7.0ga · NVIDIA-AI-IOT/deepstream_tao_apps
Please refer to DeepStream SDK FAQ - Intelligent Video Analytics / DeepStream SDK - NVIDIA Developer Forums to find out the proper pipeline settings of your camera and modify the source code. deepstream_tao_apps/apps/tao_others/deepstream-gaze-app at release/tao5.3_ds7.0ga · NVIDIA-AI-IOT/deepstream_tao_apps is open source.
Do you mean you want to use the Gaze Estimation | NVIDIA NGC model directly in your project? The model is just a pre-trained sample model, you may refer to Get Started with TAO Toolkit | NVIDIA Developer | NVIDIA Developer to customize and train the model for your project.
As for the app, the deepstream_tao_apps/apps/tao_others/deepstream-gaze-app at release/tao5.3_ds7.0ga · NVIDIA-AI-IOT/deepstream_tao_apps is open source, you can check the source code for how the data is transferred through DeepStream SDK interfaces for inferencing. All the interfaces have been introduced in Welcome to the DeepStream Documentation — DeepStream documentation
You may choose the proper methods based on your own requirement and the resources you already have.