Restore dataset card README with updated statistics

README.md

@@ -27,11 +27,24 @@ configs:
 
 # SparseVideoNav Datasets
 
-This private repository contains the processed SparseVideoNav IFN and BVN datasets.
-Images are stored in compressed tar.zst shards. Each shard preserves relative paths such as `images/<sequence>/rgb/000.jpg`.
+![SparseVideoNav dataset overview](assets/dataset_mosaic.png)
 
-The released annotations keep `id`, `video`, `actions`, and `instructions`; `data.jsonl` additionally repeats useful indexing metadata for loading.
-All images in this version have been processed by EgoBlur for face and license-plate blurring.
+This repository contains the real-world navigation datasets released with [OpenDriveLab/SparseVideoNav](https://github.com/OpenDriveLab/SparseVideoNav):
+
+- **BVN**: Beyond-the-View Navigation.
+- **IFN**: Instruction-Following Navigation.
+
+Project links:
+
+- Project page: https://opendrivelab.com/SparseVideoNav
+- GitHub: https://github.com/OpenDriveLab/SparseVideoNav
+- Paper: https://arxiv.org/abs/2602.05827
+
+## Dataset Summary
+
+SparseVideoNav studies real-world vision-language navigation with sparse future video generation. The datasets contain language instructions, RGB frame sequences, and low-level navigation actions. The number of actions matches the number of RGB frames for every released episode.
+
+This repository version contains the processed IFN and BVN subsets. All RGB frames have been processed with EgoBlur for face and license-plate blurring. At the released sampling rate of **4 fps**, the current IFN+BVN release contains **121.74 hours** of navigation data.
 
 | Subset | Episodes | RGB frames | Duration @ 4 fps | Task |
 | --- | ---: | ---: | ---: | --- |
@@ -41,21 +54,118 @@ All images in this version have been processed by EgoBlur for face and license-p
 
 Duration is computed as `num_frames / 4 / 3600`.
 
-## Structure
+## Repository Structure
+
+Images are stored in compressed tar shards to avoid hundreds of thousands of small files in the Hugging Face repository. Each shard preserves the original relative paths.
+
+```text
+.
+├── README.md
+├── assets/
+│   └── dataset_mosaic.png
+├── bvn/
+│   ├── annotations.json
+│   ├── data.jsonl
+│   ├── merge_info.json
+│   ├── shard_manifest.jsonl
+│   └── shards/
+│       ├── bvn-00000.tar.zst
+│       └── ...
+└── ifn/
+    ├── annotations.json
+    ├── data.jsonl
+    ├── merge_info.json
+    ├── shard_manifest.jsonl
+    └── shards/
+        ├── ifn-00000.tar.zst
+        └── ...
+```
+
+Current shard counts:
+
+| Subset | Shards | Compressed shard bytes |
+| --- | ---: | ---: |
+| `bvn` | 8 | 14,597,684,355 |
+| `ifn` | 9 | 16,623,840,035 |
+
+## Data Format
+
+Each line in `bvn/data.jsonl` or `ifn/data.jsonl` is an episode-level JSON object.
+
+| Field | Type | Description |
+| --- | --- | --- |
+| `dataset` | string | Dataset subset name, either `bvn` or `ifn`. |
+| `subset` | string | Release subset marker. The current release uses `main`. |
+| `episode_id` | string | Unique episode identifier. This matches the `id` field in `annotations.json`. |
+| `instruction` | string | Primary natural-language navigation instruction. |
+| `instructions` | list[string] | Instruction list. Current records contain one instruction. |
+| `task_type` | string | Task label, e.g. `beyond_the_view_navigation` or `instruction_following_navigation`. |
+| `split` | string | Dataset split. Current release uses `train`. |
+| `image_dir` | string | Relative episode image directory after extraction. |
+| `rgb_dir` | string | Relative RGB frame directory after extraction. |
+| `num_frames` | integer | Number of RGB frames in the episode. |
+| `num_actions` | integer | Number of low-level actions. This matches `num_frames`. |
+| `actions` | list[object] | Per-frame low-level navigation actions. Each action has `dx`, `dy`, and `dyaw`. |
+
+Each action object contains:
+
+| Field | Type | Description |
+| --- | --- | --- |
+| `dx` | float | Relative forward/backward displacement for the corresponding step. |
+| `dy` | float | Relative lateral displacement for the corresponding step. |
+| `dyaw` | float | Relative yaw change for the corresponding step. |
+
+Example:
+
+```json
+{
+  "dataset": "ifn",
+  "episode_id": "<episode_id>",
+  "instruction": "please go along with the rail until you are near by a red cone.",
+  "num_frames": 177,
+  "num_actions": 177,
+  "rgb_dir": "images/<episode_dir>/rgb",
+  "actions": [{"dx": 0.0429, "dy": -0.0311, "dyaw": 0.0271}]
+}
+```
+
+`annotations.json` stores the annotation records with the core fields `id`, `video`, `actions`, and `instructions`. `shard_manifest.jsonl` stores shard-level metadata, including the shard path, episode ids, raw byte size, compressed byte size, and frame count.
+
+## Usage
+
+Load episode metadata with Hugging Face Datasets:
+
+```python
+from datasets import load_dataset
+
+bvn = load_dataset("OpenDriveLab/SparseVideoNav", "bvn")
+ifn = load_dataset("OpenDriveLab/SparseVideoNav", "ifn")
+```
+
+Download and inspect shards:
+
+```bash
+tar -I zstd -tf ifn/shards/ifn-00000.tar.zst | head
+tar -I zstd -xf ifn/shards/ifn-00000.tar.zst
+```
+
+After extraction, image paths resolve to paths such as:
 
 ```text
-bvn/
-  annotations.json
-  data.jsonl
-  merge_info.json
-  shard_manifest.jsonl
-  shards/bvn-00000.tar.zst
-ifn/
-  annotations.json
-  data.jsonl
-  merge_info.json
-  shard_manifest.jsonl
-  shards/ifn-00000.tar.zst
+images/<episode_dir>/rgb/000.jpg
 ```
 
-Generated at `2026-07-06 14:23:43` from `/mnt/HDD-raid/siqiteam/140h_data`.
+## License
+
+The dataset is released under CC BY-NC-SA 4.0.
+
+## Citation
+
+```bibtex
+@article{zhang2026sparse,
+  title={Sparse Video Generation Propels Real-World Beyond-the-View Vision-Language Navigation},
+  author={Zhang, Hai and Liang, Siqi and Chen, Li and Li, Yuxian and Xu, Yukuan and Zhong, Yichao and Zhang, Fu and Li, Hongyang},
+  journal={arXiv preprint arXiv:2602.05827},
+  year={2026}
+}
+```