Return and show bounding box confidence

Show bounding box on screen too

Unify batched and non-batched versions

Show FPS on demo video

Resize in keeping aspect ratio in visualization

Add model format (ONNX/Engine) & input size detection (based on file header, not on filename) for RTMO

Bugfix for batch demo: add padding if remaning number of frames is not equal to batch size

Make ONNX models compatible with ONNXruntime's TensorrtExecutionProvider

Use RTMO_GPU_Batch to demo