https://github.com/timschneider42/python-natnet-client

Python client for Optitrack NatNet streams.
https://github.com/timschneider42/python-natnet-client

natnet natnet-sdk optitrack python

Last synced: about 2 months ago
JSON representation

Python client for Optitrack NatNet streams.

• Host: GitHub
• URL: https://github.com/timschneider42/python-natnet-client
• Owner: TimSchneider42
• License: mit
• Created: 2021-12-02T15:00:04.000Z (about 3 years ago)
• Default Branch: master
• Last Pushed: 2024-03-08T09:46:23.000Z (10 months ago)
• Last Synced: 2024-03-08T10:52:45.281Z (10 months ago)
• Topics: natnet, natnet-sdk, optitrack, python
• Language: Python
• Homepage:
• Size: 37.1 KB
• Stars: 4
• Watchers: 1
• Forks: 2
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# Python NatNet Client

Python client for Optitrack NatNet streams.

## Installation

Install this package via pip:

```bash

pip install git+https://github.com/TimSchneider42/python-natnet-client

```

## Usage

The following example highlights the basic usage of this package:

```python

import time

from natnet_client import DataDescriptions, DataFrame, NatNetClient

def receive_new_frame(data_frame: DataFrame):

    global num_frames

    num_frames += 1

def receive_new_desc(desc: DataDescriptions):

    print("Received data descriptions.")

num_frames = 0

if __name__ == "__main__":

    streaming_client = NatNetClient(server_ip_address="127.0.0.1", local_ip_address="127.0.0.1", use_multicast=False)

    streaming_client.on_data_description_received_event.handlers.append(receive_new_desc)

    streaming_client.on_data_frame_received_event.handlers.append(receive_new_frame)

    with streaming_client:

        streaming_client.request_modeldef()

        for i in range(10):

            time.sleep(1)

            streaming_client.update_sync()

            print(f"Received {num_frames} frames in {i + 1}s")

```

In this example, we first instantiate `NatNetClient` with the connection parameters and attach one callback function to

each of its events. The `streaming_client.on_data_description_received_event` event is triggered whenever a new data

description packet arrives, while the `streaming_client.on_data_frame_received_event` event is triggered on each

incoming data frame. For the configuration of the NatNet server, please refer to the official documentation.

You can process data synchronously, as in this example, by calling `streaming_client.update_sync()` in your run loop.

Alternatively, you can call `streaming_client.run_async()` once after connecting, which will handle data asynchronously

in two additional threads.

We then use the `streaming_client` instance as a context manager, which is equivalent to

calling `streaming_client.connect()` (and `streaming_client.shutdown()` afterwards). After the client has been

connected, we request the model definitions from the server, which causes it to send a data description packet. Note

that data frames do not have to be explicitly requested, but are continuously streamed once a connection has been

established.

Apart from requesting model definitions, the `NatNetClient` class allows sending arbitrary commands to the NatNet server

via the `send_command` and `send_request` functions. For a list of different commands and requests, please refer to the

official documentations.

## Notes

As of Motive version 2.3, the marker positions of rigid bodies are only transmitted correctly if "Y-up" is selected in

the streaming pane. If "Z-up" is selected, the frame of the rigid bodies is rotated but the marker positions are not,

resulting in wrong positions of the markers relative to the rigid body.