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Evaluation: 4-round policy, validations store, prev/next, copy/clear, build flag
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---
title: OpenCS2 Dataset - Viewer
emoji: 🎯
colorFrom: yellow
colorTo: gray
sdk: docker
app_port: 7860
pinned: false
license: mit
short_description: Browse the CS2 dataset by match, map, round, and POV.
---
# OpenCS2 Dataset - Viewer
![OpenCS2 Dataset β€” 10 tick-aligned player POVs, inputs, world state, and audio, built from professional HLTV demos.](static/header.webp)
Browser for [`blanchon/cs2_dataset_render`](https://huggingface.co/datasets/blanchon/cs2_dataset_render), the OpenCS2 dataset: a rendered Counter Strike 2 dataset built from professional HLTV demos. The viewer lists every match, map, and round in the dataset and plays the 10 synchronized player POVs back-to-back on a single timeline β€” without downloading the full archive.
It's a pure-frontend SvelteKit app: parquet indexes are read in the browser via [`hyparquet`](https://github.com/hyparquet/hyparquet), preview MP4s stream from Hugging Face, and 10 chunked players stay in sync through a custom [`mediabunny`](https://mediabunny.dev/) pipeline.
## Links
- **Dataset:** <https://huggingface.co/datasets/blanchon/cs2_dataset_render>
- **Live viewer (HF Space):** <https://huggingface.co/spaces/blanchon/opencs2-dataset-viewer>
- **Source dataset (raw demos):** <https://huggingface.co/datasets/blanchon/cs2_dataset_demo>
- **GitHub:** <https://github.com/julien-blanchon/opencs2-dataset>
- **Author:** [Julien Blanchon](https://guybrush.ink/) β€” [@JulienBlanchon](https://x.com/JulienBlanchon)
## Motivation
Counter Strike 2 is an interesting environment for sequential decision-making: long horizons, partial observability, dense visual signal, spatialized audio, 5 vs 5 multi-agent dynamics, and a competitive equilibrium that is genuinely hard. Pro HLTV demos give us tens of thousands of hours of expert play, but until now they've lived in a binary `.dem` format that is not directly trainable.
This dataset turns those demos into rendered, frame-accurate, fully-annotated training data. A few of the things it makes tractable:
- **Behaviour cloning / VLA policies.** `(frame, audio) β†’ action` for vision-conditioned action models.
- **Inverse Dynamics Models (IDM).** `(frame_t, frame_{t+k}) β†’ action` to recover actions from unlabelled video β€” the workhorse for VPT-style pre-training.
- **Forward dynamics / world models.** `(frame, action) β†’ frame_{t+1}` with all 10 player POVs of the same world state available as supervision.
- **Spatial-audio conditioning.** Per-player stereo recorded relative to each agent's position and orientation, so models can learn to localize footsteps, gunfire, and callouts.
- **Multi-agent training.** All 10 perspectives of the same round are kept aligned tick-for-tick β€” useful for collaborative policies, opponent modelling, and multi-player world models.
- **Multi-view SfM / depth benchmark.** Ground-truth camera intrinsics and metric depth maps from 10 synchronized viewpoints make this a clean reference for structure-from-motion, multi-view stereo, and camera pose estimation.
## What's recorded
For every chunk (≀ 1 minute, one player POV):
- **Video** β€” 1280Γ—720 @ 32 fps, near-lossless H.264. One stream per player; ten POVs per round all tick-aligned.
- **Audio** β€” per-player stereo, mixed from each agent's position and orientation (footsteps, gunfire, callouts).
- **Inputs** β€” every tick: keyboard state, mouse delta, fire/jump/use, weapon switches.
- **World state** β€” every tick, for all 10 players: position, velocity, view yaw/pitch, camera intrinsics, health, armor, ammo, primary/secondary weapon, alive flag.
- **G-buffers (coming soon)** β€” per-pixel luminance, depth map, and vertex-ID map for self-supervised pretraining and dense prediction heads.
- **Tick-perfect alignment** β€” every signal is sampled on the same CS2 tick clock. No drift, no resampling artifacts, no per-stream timestamp reconciliation.
## Dataset
`blanchon/cs2_dataset_render`, derived from `blanchon/cs2_dataset_demo`. Licensed under `CC-BY-4.0`.
Each row is a one-minute-or-shorter chunk of a single player's POV. Four configs are exposed:
| Config | Row | Use |
| -------------------- | ------------------------------------------------------------------------------------- | ------------------------------------- |
| `previews` (default) | One low-res `preview.mp4` per chunk + 1 Hz inputs/world sidecars | Cheap browsing, viewer, sanity checks |
| `chunks` | Path-only references to `video.mp4` + `audio.wav`, with embedded inputs/world streams | Full-resolution training |
| `matches` | One row per `(match_id, map_name)` with team/event/date metadata | Index / filtering |
| `rounds` | One row per `(match_id, map_name, round)` with tick boundaries | Index / filtering |
### Filesystem layout
```text
index/
manifest-<machine>-<uuid>.parquet # matches index
rounds-<machine>-<uuid>.parquet # rounds index
data/
match_id=<id>/map_name=<map>/player=<0-9>/
chunks-preview-<machine>-<uuid>.parquet
chunks-full-<machine>-<uuid>.parquet
chunks/chunk_<n>/{video.mp4,audio.wav}
previews/chunk_<n>/{preview.mp4,inputs.preview.json,world.preview.jsonl}
```
Hive-style `key=value` partitioning lets you prune at the path level. Recording starts at `freeze_end_tick` and stops at the player's death tick (or round end for survivors), so player streams have different durations within the same round.
### Quick query
```python
from datasets import load_dataset
# Default lightweight preview rows
previews = load_dataset("blanchon/cs2_dataset_render", split="train", streaming=True)
# Full training rows, columnar load
chunks = load_dataset(
"blanchon/cs2_dataset_render", "chunks",
split="train", streaming=True,
columns=["video", "audio", "inputs", "worlds", "match_id", "round", "player"],
filters=[("player", "==", 0)],
)
```
```sql
-- Match index via DuckDB
SELECT match_id, map_name, team1, team2, event, match_date
FROM 'hf://datasets/blanchon/cs2_dataset_render/index/manifest-*.parquet'
LIMIT 20;
```
## Develop
```sh
bun install
bun run dev # vite dev server
bun run build # static build β†’ dist/
bun run preview # serve the build
bun run check # svelte-check
```
The repo ships a `Dockerfile` and `serve.ts` that mirror the Hugging Face Space deployment.
### Build flags
- `PUBLIC_DISABLE_EVAL=1` β€” hide the evaluation surface (header toggle, eval bar, flag dialog) for public deploys. Set at build time only (`PUBLIC_DISABLE_EVAL=1 bun run build`); the eval module stays in the bundle but is never rendered.
## Viewer internals
- **`hyparquet` + `hyparquet-compressors`** read the match and round parquet shards directly from `hf://` URLs. No server, no DuckDB, no WASM bundle larger than necessary.
- **`mediabunny`** powers the 10 chunked POV players. One round's worth of `preview.mp4` chunks per player is concatenated into a single virtual timeline; players who died early have shorter timelines and gracefully fall out.
- **`world.preview.jsonl`** drives the minimap (player positions, team, alive/dead, weapon) and the per-tick state overlay.
- **`inputs.preview.json`** drives the input-overlay HUD (movement keys, mouse, fire/jump).
The whole viewer is a static SvelteKit build β€” there is no backend.
## Citation
```bibtex
@misc{blanchon2026opencs2,
author = {Julien Blanchon},
title = {OpenCS2 Dataset},
year = {2026},
publisher = {Hugging Face},
howpublished = {\url{https://github.com/julien-blanchon/opencs2-dataset}},
}
```
## License
Code: MIT. Dataset: CC-BY-4.0.