TABLE I: Context annotation guideline.
Attribute Attribute Value Description
time of day daytime Selected if any other condition does not fit.
dawn dusk It is selected in case of a low-lying sun, dawn/dusk, or twilight.
night There is no natural light, the sky is black, and the vehicle is not inside a building,
tunnel, or similar.
undefined The environment is not visible, e.g., because the vehicle is inside a building,
tunnel, or similar.
sky clear Not a single cloud is visible in the sky.
partly cloudy At least one cloud is visible in the sky.
overcast Clouds completely cover the sky.
foggy Fog is visible, or visibility is in general low.
undefined Clouds are not visible/recognizable because the sky is too light/dark or obscured,
e.g., by trees, buildings, or other obstacles.
illumination natural Selected if any other condition does not fit.
sun glare Directly or indirectly (via reflection) dazzling sun or very bright/white sky,
e.g., between buildings, at the exit of tunnels or a forest.
artificial The primary light source is artificial and is not the ego vehicle’s headlights.
Borderline case: twilight with street lighting falls in here.
dark No natural or artificial light source apart from the ego vehicle’s headlights.
precipitation nothing No raindrops or snowflakes are visible in the image.
rain There are large raindrops on the windshield clearly distinguishable from dirt.
snow Falling snowflakes are well visible in the image.
infrastructure inner city There are dense buildings all around, and everything else does not apply.
industrial There are factories or similar visible.
highway The vehicle is on the highway, and the surrounding area does not matter.
suburb There is more than one building visible and some greenery.
nature No or very few buildings/infrastructure are visible (max. one small building).
parking lot Recognizable parking lot markings or appropriate signs are visible.
gas station Gas station or parts of it are visible somewhere in the picture (roadside also suffices).
undefined Surroundings are not clearly recognizable/obscured/too dark/too light
or the vehicle is in a tunnel, building, or similar.
road dry There is no water, mud, or snow on the road.
(Drivable area only,
edge of roadway
and sidewalk are
ignored.)
wet At least wetness is recognizable on the road, e.g., via reflection.
slushy There is recognizable snow mud, and the road is not completely covered by snow.
snowy The road is completely covered by snow.
undefined State is not clearly discernible, or the passable area is largely obscured/too dark.
tunnel true, false The vehicle is recognizably in or just in front of a tunnel.
construction site true, false Construction site markings are somewhere in the picture. Construction vehicles alone are
not sufficient.
clear windshield true, false The windshield is unclear if dirt, raindrops, leaves, or the windshield wipers is blocking
the view. Other obstacles (e.g., mirror, dashboard, hood) does not count as unclear.
light exposure true, false In the image, there is a light source, e.g., sun or spotlight, and the light shines into the
camera. For example, oncoming traffic, streetlights, or rising sun.
reflections true, false The reflection of the dashboard or objects (ghost objects) in the windshield are labeled as
true. Reflections of objects in the hood or glass facades do not count.
