Questions and answers

Which insects does Rekkefly work with?

Any tethered insect whose beating wings leave a motion-blur envelope in the image: flies (Drosophila and larger), bees, moths. The example that ships with it is a Bogong moth, and the synthetic test flies have six legs, antennae and translucent wings.

Does it need a particular camera?

No. Any camera your system can use as a webcam works: USB machine-vision cameras with UVC support, webcams, and built-in cameras. For wing-stroke amplitude, the exposure should be long enough to blur several wingbeats into an envelope. Video files and network streams work too.

How fast is it? Can it keep up with a high-speed camera?

Tracking takes about 0.3 ms per 640×480 frame, so one rig can process about 3,000 frames/s of tracking alone, and about 1,000 frames/s when it also has to decode MJPEG video. See Performance.

What is the latency?

A frame is tracked on the capture thread the moment it arrives, and its measurement is published immediately: the added delay is the tracking time (about 0.3 ms) plus sending a small message. The camera’s own exposure and transfer usually dominate.

Can I use it with my existing Kinefly experiment code?

Yes. Rekkefly publishes the same ZMQ JSON message as the Kinefly Docker bridge, on the same default port. See Coming from Kinefly.

Does it measure wingbeat frequency?

Not yet. Rekkefly measures stroke amplitude (the envelope’s leading edge), as Kinefly does. Wingbeat frequency and stopped-flight detection are not implemented.

Is it accurate?

On synthetic flies with known angles, the median error is about 0.25°, and no frame was off by more than 4° even with legs kicking through the wings. On the real Bogong moth, which has no ground truth, painted antennae moved L − R on 3 of 900 frames. See Evidence, including what has not been verified yet.

Why “Rekkefly”?

ರೆಕ್ಕೆ (rekke) is Kannada for wing. Rekkefly is the wing-tracker for flies, and the successor to Kinefly.

Is it free?

Yes: free and open source under the MIT License, for any use, including commercial. If you use it in published research, please cite it.

Can an AI agent run my rigs?

Yes, through the built-in MCP server. It can start and stop rigs, look at the tracking overlay, move markers, record and measure trials. Agents only get the access you give the MCP client that runs it.

Does Rekkefly send data anywhere?

Only where you configure it: ZMQ and UDP measurements to the addresses in the config. It has no telemetry and checks for nothing online.

Can I run it without a screen?

Yes: --headless, or rigs from a manifest with --rigs … --headless. A build without the GUI and camera support is also possible (cargo build --release --no-default-features) for offline analysis on servers.