Events Recorder

Basic Knowledge Requirements

Before diving into this example, here's a quick heads-up on what you'll need to be familiar with:

1. Python Programming: It's essential to be well-versed in Python, as the example leverages foundational concepts such as functions, conditional statements, and command-line argument parsing using the argparse module.
2. Asynchronous Programming with asyncio: Familiarity with Python's asyncio for writing concurrent code using the async/await syntax.
3. farm-ng Recorder Service Overview: This overview provides a base understanding of the gRPC service the client you create will connect to.

In the Events Recorder example we show how to record events from farm-ng-brain using the EventClient class.

You can either run this example directly on a brain by ssh'ing in, or use your local PC. If using your local PC, it should be either connected to the same local network as the brain or linked to it through tailscale.

1. Install the farm-ng Brain ADK package

2. Setup

tip

It is recommended to also install these dependencies and run the example in the brain ADK virtual environment.

Create first a virtual environment

python3 -m venv venv
source venv/bin/activate

# Assuming you're already in the amiga-dev-kit/ directory
cd farm-ng-amiga/py/examples/events_recorder

3. Install the example's dependencies

pip3 install -r requirements.txt

4. Code overview

In the provided example, we show how to implement the recorder/start and recorder/stop requests to start and stop the recording of events. We also provide two example profiles record_camera_config.json and record_fiter_config.json that can be used to record the camera and filter events.

async def start_recording(
    service_config: EventServiceConfig, recording_profile: EventServiceConfig
) -> None:
    reply = await EventClient(service_config).request_reply(
        "recorder/start", recording_profile, decode=True
    )
    print(reply)


async def stop_recording(service_config: EventServiceConfig) -> None:
    reply = await EventClient(service_config).request_reply(
        "recorder/stop", Empty(), decode=True
    )
    print(reply)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(prog="amiga-camera-calibration")
    parser.add_argument(
        "--service-config", type=Path, required=True, help="The camera config.")

    subparsers = parser.add_subparsers(dest="command")

    start_command = subparsers.add_parser("start_recording", help="Start recording.")
    start_command.add_argument(
        "--recording-profile", type=Path, required=True, help="The recording profile.")

    stop_command = subparsers.add_parser("stop_recording", help="Stop recording.")

    args = parser.parse_args()

    # Create a client to the Recorder service
    service_config: EventServiceConfig = proto_from_json_file(
        args.service_config, EventServiceConfig()
    )

    if args.command == "start_recording":
        recording_profile = proto_from_json_file(
            args.recording_profile, EventServiceConfig()
        )
        asyncio.run(start_recording(service_config, recording_profile))

    if args.command == "stop_recording":
        asyncio.run(stop_recording(service_config))

5. Execute the Python script

info

To run this script from your PC, you need to update the service_config.json by modifying the host field with your Amiga brain name.

Please check out Amiga Development 101 for more details.

To start recording the camera events, run the following command:

python main.py --service-config service_config.json start_recording --recording-profile record_camera_config.json

You should see a similar output:

string_value: "/mnt/data/2023_09_28_10_24_07_212687_lead-mango"

In order to stop the recording, run the following command:

python main.py --service-config service_config.json stop_recording

Finally, to validate that the events have been recorded, you can run the following command:

python -m farm_ng.core.events_file_reader playback /mnt/data/2023_09_28_10_24_07_212687_lead-mango.0000.bin