| --- |
| pretty_name: Blender6D Track4D v3 BF16 preprocessed conditions |
| language: |
| - en |
| size_categories: |
| - 10K<n<100K |
| tags: |
| - blender6d |
| - synthetic |
| - video |
| - 3d |
| - world-model |
| - precomputed-latents |
| - bf16 |
| --- |
| |
| # Blender6D Track4D v3 conditions — BF16 storage |
|
|
| Preprocessed conditioning data for **5,970 synthetic scenes and 23,880 directed |
| camera pairs**. Each scene supplies `cam_00 → cam_01`, `cam_01 → cam_02`, |
| `cam_02 → cam_03`, and `cam_03 → cam_00` at the same times. |
|
|
| ## BF16 revision, 2026-10-24 |
|
|
| Memory and control latents are now stored as **BF16 with lossless Zstandard |
| compression**, using `bf16_dynamic_zstd_v1`. Camera and geometry dtypes are preserved. |
|
|
| **These files were converted from the prior INT8 release.** The conversion stores |
| exactly the BF16 values returned by the previous loader, verified bit-for-bit for |
| every tensor. It does **not** recover precision lost during the original INT8 |
| quantization and is **not** a fresh full-precision inference run. Per-sample |
| `precision_provenance` records `origin=dequantized_int8`, the prior quantization |
| errors, and `original_precision_recovered=false`. Source RGB, geometry, cameras, |
| poses, captions, pair identities, and frame selection are unchanged. |
|
|
| The previous INT8 publication remains available at revision |
| `f3f92e5cf02a19b48a89bb58a7b4ee91bfc36ffe`. |
|
|
| ## Contents |
|
|
| - 33 target RGB frame indices at 30 fps; input resolution 704 × 1280. |
| - Five latent anchors; BF16 memory shape `[128, 5, 22, 40]` and control shape |
| `[2, 128, 5, 22, 40]`, with SANA normalization. |
| - English captions, camera information, target indices, condition-image references, |
| quality reports, object poses, and per-pair provenance. |
| - Metric geometry in metres: foreground depth uses a 0.001 conversion from source |
| millimetres; background geometry comes from the source Blender scene. |
| - All detected dynamic regions are excluded before static-memory construction. |
| - Cross-camera identity conditions; no bank-shuffle variants for Blender6D. |
|
|
| **Raw RGB videos, original `.blend` files, external target latents, and text |
| embeddings are not included.** Those inputs must be supplied separately when |
| required by training. SpatialVID and Stereo4D outputs are separate datasets. |
|
|
| ## Files |
|
|
| `shards/train-00000.tar` through `shards/train-00046.tar` contain checksum-verified |
| per-pair `conditions.zip`, `pairs-0000.jsonl`, `receipt.json`, and |
| `bf16-storage.json` under `data/scene_XXXXXX__cam_XX-cam_XX/`. |
|
|
| The top-level `pairs.jsonl` is portable: archive paths are relative to the download |
| root and RGB references use a `source-videos/` placeholder. Per-pair manifests and |
| archive metadata preserve original producer paths as provenance. Use the top-level |
| manifest after resolving paths for your server. |
|
|
| `checksums.json` records SHA-256 and byte counts for the publication files. |
| `provenance/` contains the preprocessing configuration, completion audit, and BF16 |
| migration summary. Training checkpoints, execution logs, credentials, and rollback |
| copies are excluded. |
|
|
| ## Download and prepare |
|
|
| ```python |
| from huggingface_hub import snapshot_download |
| snapshot_download( |
| repo_id="HugMinjun/Blender6D-Track4D-v3", |
| repo_type="dataset", |
| local_dir="blender6d-track4d-v3-bf16", |
| ) |
| ``` |
|
|
| Use Python 3.12+, or a Python 3.11 release supporting tar extraction filters: |
|
|
| ```bash |
| python blender6d-track4d-v3-bf16/prepare_manifest.py \ |
| --root blender6d-track4d-v3-bf16 \ |
| --video-root /path/to/train_geometry_rgb_instance_motion_gmos_v2 \ |
| --verify-shards |
| ``` |
|
|
| The RGB root must contain `scene_XXXXXX/cameras/cam_XX/rgb.mkv`. The preparation |
| script extracts the archives, resolves paths, and writes `pairs.local.jsonl`. |
| It reports missing RGB videos without providing those videos. |
|
|
| Use a Track4D loader that recognizes `bf16_dynamic_zstd_v1`. In the prior |
| `training_preprocessing/compact.py`, add this identifier to `READABLE_FORMATS`; |
| the existing decoder already leaves BF16 tensors without `_qscale_` unchanged. |
| The included `bf16_loader.py` can also inspect individual samples independently: |
|
|
| ```python |
| import json |
| from bf16_loader import load_conditions |
| |
| with open("pairs.local.jsonl") as f: |
| row = json.loads(next(f)) |
| sample = load_conditions(row["archive"], row["sample"]) |
| assert str(sample["memory_latent"].dtype) == "torch.bfloat16" |
| ``` |
|
|
| This minimal reader requires `torch`, `safetensors`, and `zstandard`; it does not |
| load RGB or create training targets. The initial condition latent must come from |
| the external target's exact first latent according to `external_target_contract`. |
|
|
| <!-- static-memory-holefill-20261025:start --> |
| ## Static memory correction (2026-10-25) |
|
|
| Use the [static memory correction folder](holefill-fix-20261025/README.md) with both the |
| original cross-camera release and `temporal-same-camera-33/`. It repairs |
| 6,187 affected condition archives while preserving all original downloads. |
| The corrected static hole-fill pyramid can materially change affected memory |
| latents. Other condition tensors, targets, captions and RGB references are unchanged. |
|
|
| Download `holefill-fix-20261025/` and run its `apply_patch_manifest.py` on each base release's |
| prepared local manifest. Use the resulting corrected manifest for training; |
| do not concatenate old and corrected manifests. The correction contains only |
| replacement archives, so existing base downloads can be reused. |
| <!-- static-memory-holefill-20261025:end --> |
|
|
