The Bogong moth example

Every download includes 30 seconds of a real tethered Bogong moth (Agrotis infusa), filmed from above at 30 fps with its head down: samples/bogong-moth.avi (640×480, 900 frames, MJPEG, 10 MB). It plays whenever Rekkefly cannot open a camera, so you can learn every feature right after installing, and it is the real-footage test behind Rekkefly’s evidence.

Rekkefly tracking the Bogong moth with the debug traces open

Try it

rekkefly samples/bogong-moth.avi --loop        # watch it; the video brings its own markers
rekkefly --config configs/bogong-moth.toml     # the example config; your edits are saved
rekkefly track samples/bogong-moth.avi         # every frame, as fast as possible

In an installed app the files are in the app’s folders (for example /usr/share/rekkefly/samples/ on Ubuntu); portable folders have them beside rekkefly. On Ubuntu the app menu also has Open the Bogong moth example.

rekkefly track prints a summary:

Tracked 900 frames of bogong-moth.avi (640×480, robust detector, the video's own markers) in 0.87 s: 1032 frames/s, 340 µs tracking per frame (99% under 667 µs)
  left     mean   -20.9°  sd  28.0°  range  -66.2° …  +40.0°  (900 frames)
  right    mean   -15.1°  sd  21.0°  range  -59.6° …  +19.8°  (900 frames)
  L−R      mean    -5.9°  sd  11.1°  range  -27.5° …  +38.9°  (900 frames)

Why it is a good test

Antennae and legs reach out beside the wing sectors near the head. Extend a sector over them and a classic detector starts reporting them as the wing.
One wing is faint. The moth’s left wing (image right) is often barely lit.
Strobing. The wingbeat is faster than the camera, so each frame catches a different moment of it. L and R swing by tens of degrees between frames, while L − R, which compares the two wings at the same moment, stays steady.
Bright on dark. The moth is lit from above, so it is brighter than the background: dark_on_light = false. The display inverts it, so every rig looks the same on screen.

How its markers were placed

The markers were measured from the video, not placed by eye:

Marker	Value	How
Hinges	(371.5, 239) and (334.5, 239)	Straight lines fitted to one wing’s leading edge in 190 frames all pass within 0.7 px (median) of one point, (334.5, 239). The other wing’s fits gave (370, 242); the hinges were set symmetrically about the body axis
Inner radius	20 px	Just past the body
Outer radius	150 px	Inside the wing blur
Sector	−70° to +55° (image degrees, each wing mirrored)	Clear of the thorax toward the tail, past the most forward stroke, short of the legs
Leading edge	`primary_edge = "toward_head"`	Where the wing gives way to background on the head side

Compared with hinges placed by eye 20 px away, this halved the L − R noise. Starting the sectors at −75° instead of −70° let one sector clip the thorax and caused L − R spikes. The full config, with comments, is configs/bogong-moth.toml.

Settings on the Bogong moth: the robust detector, leading edge toward the head, hinges at the wing bases

The example’s markers are never saved

When the example plays because no camera opened, it uses its own markers, scaled to your camera’s processing size, and shows a banner. Your rig’s own markers are untouched: nothing from the example is ever saved into your config. Click Retry camera once a camera is connected.

The same rule applies to any video: opening recording.avi for one run picks up recording.toml beside it, if there is one, for that run only.

Use your own footage as the example

Put a clip at <your Rekkefly folder>/samples/sample.avi (on a Mac, ~/Library/Application Support/Rekkefly/samples/sample.avi), or set the environment variable REKKEFLY_SAMPLE=/path/to/clip.avi. It then plays instead of the moth. A sample.toml beside it gives it its own markers.

Cut 30 seconds from a recording:

rekkefly clip recording.avi sample.avi --start 60 --duration 30 --quality 75

At quality 75 the moth tracks the same as from lossless frames, at a tenth of the size.