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README.md

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-license: mit
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+---
+license: mit
+---
+*EgoWalk Trajectories*
+
+This is the extracted version of the EgoWalk dataset, obtained from the [raw one](https://huggingface.co/datasets/EgoWalk/traverse).
+Please check the [API for this dataset](https://github.com/egowalk/egowalk-dataset) for the basic usage.
+
+**Data format**
+The data is mainly organized in following directories:
+- *data*: includes csv with the main per-frame annotations - video name, frame index, UTC timestamp, camera pose (may be `null` due to odometry failures, see next sections)
+- *video*: includes video files that are referenced in *data*. Lossy encoding is used for RGB channel, lossless - is for Depth channel.
+- *annotations*: includes language goal annotations for the selected frames. We release to versions of annotations: *normal* - the main version, and *brief* - the version with slightly more brief sentences.
+- *meta*: includes additional metadata, namely, approximate camera heights, camera params, list of trajectories, etc.
+
+**Notes on the odometry**
+[ZED SDK](https://www.stereolabs.com/en-ru/developers/release) was used to calculate the odometry from the raw data. This odometry is still imperfect, and sometimes may result in odometry failures of two kinds:
+- `nulls`: odometry method failed to compute the pose at this particular timestamp
+- Reinitialization: due two large amount of sequential failures odometry was re-initialized in the middle of trajectory, and re-initialized pose starts in zero.
+API includes some mechanisms to process such cases, such as [cutters](https://github.com/egowalk/egowalk-dataset/blob/main/egowalk_dataset/datasets/gnm/cutters.py).