update rendered dataset README

README.md

@@ -50,7 +50,10 @@ rendered training dataset.
 
 - `previews` (default): one low-resolution `preview_video` row per chunk with
   the input overlay baked in. Preview MP4s are stored as loose files and the
-  Parquet stores only their relative paths, so filtering stays cheap. The
+  Parquet stores only their relative paths, so filtering stays cheap. Each
+  preview directory also carries lightweight `inputs.preview.json` and
+  `world.preview.jsonl` sidecars sampled at 1 Hz for debugging/browsing without
+  loading the heavy `chunks` config. The
   `preview_path` column is relative to the preview Parquet directory
   (`previews/chunk_000123/preview.mp4`), while `preview_video.path` is an
   `hf://datasets/<repo>@main/...` URI so Hugging Face's dataset viewer can
@@ -74,7 +77,10 @@ data/
         video.mp4
         audio.wav
     previews/
-      chunk_<ordinal>/preview.mp4
+      chunk_<ordinal>/
+        preview.mp4
+        inputs.preview.json
+        world.preview.jsonl
 index/
   manifest-<machine>-<uuid>.parquet
   rounds-<machine>-<uuid>.parquet
@@ -137,13 +143,13 @@ LIMIT 20;
 ## Partial Download
 
 ```bash
-hf download blanchon/cs2_dataset_render --repo-type dataset \\
+hf download blanchon/cs2_dataset_render --repo-type dataset \
   --include "index/*.parquet"
 
-hf download blanchon/cs2_dataset_render --repo-type dataset \\
+hf download blanchon/cs2_dataset_render --repo-type dataset \
   --include "data/match_id=2393343/**/chunks-preview-*.parquet"
 
-hf download blanchon/cs2_dataset_render --repo-type dataset \\
+hf download blanchon/cs2_dataset_render --repo-type dataset \
   --include "data/match_id=2393343/map_name=de_ancient/player=0/chunks-full-*.parquet"
 ```