Update README.md

README.md

@@ -418,6 +418,49 @@ for split_name, split_data in [("CV", cv_split), ("CS", cs_split)]:
 
 ```
 
+## Label definitions
+
+In this section we provide additional information about the labelling process to provide as much transparency as possible.
+
+There are 10 labels:
+
+- **`0|walk`** - Move around, including jogging and running and "drunk walking", but only if it is not part of some special exercise like pulling your knees up. Not when pushing a large object like a chair, but included carrying something small like an apple.
+- **`1|fall`** - The act of falling (from any previous state). Includes falling on a bed, if the process is not a controlled lying down with arms as support.
+- **`2|fallen`** - Being on the ground or a mattress after a fall.
+- **`3|sit_down`** - Sitting down on bed or chair or ground.
+- **`4|sitting`** - Sitting on bed or chair or ground.
+- **`5|lie_down`** - Lying down intentionally (in contrast to a fall) on ground or bed.
+- **`6|lying`** - Being in a lying position (in bed or on the ground) after intentionally getting into that position.
+- **`7|stand_up`** - Standing up from a fallen state, from lying or sitting. Includes getting from lying position into sitting position.
+- **`8|standing`** - Standing around without walking.
+- **`9|other`** - Any other activity, including e.g. walking while pushing an object like a chair.
+
+## Motion Types
+
+There are two types of motions, **dynamic** ones like `walk` or `stand_up` and **static** ones like `fallen`, `sitting`, `lying`.
+
+**Generally we annotate dynamic motions as soon as the first frame appears which belongs to that action**.
+
+Let's say we see a person `walk`, then `fall`. The first frame which indicates a motion which does seem to be different to `walk` is the start of `fall`. Sometimes it is necessary to have a look at a person walking to learn when the motion begins to change to something else.
+
+**For static motions the label begins with the first frame where the person comes to a resting state.** For `sit_down`, the label ends when the person reaches a state where it is no longer adjusting its body position but comes to a rest. `fall` ends when the person is no longer moving caused by the inertia of the fall. The following `fallen` might contain movement on the ground, but no movement which belongs to `fall` or `stand_up`.
+
+## Label Sequences
+
+There are some natural sequences of labels like `fall`, `fallen` and `stand_up`. However, it is not always the case that these appear together. Sometimes the person might directly stand up again without any time at rest on the ground, in this case there is no `fallen` segment. Likewise sometimes there is no sitting segment.
+
+Lying down can be on a bed or on the ground, it is intentional in contrast to `fall`. There are falls which follow `sit_down` or `lie_down` if it is from a chair or from a bed.
+
+When a person is lying in a bed and getting up to sit in the bed we label this as `stand_up`, even if the person is still sitting in the bed. A sequence could then be `lying`, `stand_up`, `sitting`, `stand_up` to describe a person which first lies down, then gets into a sitting position, waits a little, then gets fully up.
+
+Sometimes it is not perfectly clear if it is `sit_down` followed by `lie_down` or simply `lie_down`. This depends on there being a moment of rest or not. If the person spends a short amount of time in the sitting position it is the former, if the person directly goes from `sit_down` to `lie_down` without rest it is only labeled `lie_down`. Similar thoughts apply to `stand_up`.
+
+In the following video we show how we leveraged VGG VIA to perform the annotations. Note, that we pre-load the original dataset labels as visual aid, but relabel the whole video with our label definitions. In the video below, CMDFall is shown, which already provides relatively detailed labels, the original labels of other datasets are more sparse. Additionally, even CMDFall does not label all frames, but only specific segments, while our labels cover mostly every frame.
+
+The blurred out regions were added by us in post-processing to protect the subjects privacy on this page, they are not part of the original videos.
+
+<video src="https://huggingface.co/datasets/simplexsigil2/omnifall/resolve/main/annotation_remarks.webm" controls />
+
 
 ## Citation