README.md

---
license: mit
library_name: bcdl
tags:
- rdk-s100
- rdk-s100p
- d-robotics
- bpu
- hbm
- depth-estimation
- stereo
---

# Lite Any Stereo V2 for RDK S100/S100P — zero-shot stereo disparity

Compiled BPU models (`.hbm`) for the **D-Robotics RDK S100 / S100P**, ready to
load — no ONNX export, no calibration, no `hb_compile`. Built and measured with
[**BCDL**](https://github.com/ruisv/bcdl), a C++17 inference and media library
for the RDK S-series with Python bindings.

Upstream: [Lite Any Stereo V2](https://github.com/Tinker-Twins/LiteAnyStereo) (M)

> [!TIP]
> **Redistributable, including commercially.** The licence chain was checked on
> the code, the pretrained weights it started from, and the data it was trained
> on — all three, because a permissive repository badge does not by itself say
> anything about the weights. See [Licence](#licence).

## Files

| file | what it is |
|---|---|
| `las2_m_crop_nashm.hbm` | centre-crop-fit calibration, 640x480 — 38.8 MB |
| `las2_m_int16_nashm.hbm` | resize-fit calibration, 640x480 — 39.3 MB |

## Measured on an S100P

| stage | latency | throughput |
|---|---|---|
| either build | 13.70 ms | 73 FPS |

`hrt_model_exec perf`, one thread, minimum of three runs, on a board first gated
against its own previously recorded numbers. **BPU time only** — CPU
pre/post-processing is on top and is listed per task in BCDL's
[benchmark results](https://github.com/ruisv/bcdl/blob/main/benchmarks/RESULTS.md).

## Use it

```bash
conda install -c https://mirrors.ruis.ai/conda -c conda-forge bcdl
```

```python
import bcdl
engine = bcdl.Engine("las2_m_crop_nashm.hbm")
print(engine.input_shape(0), engine.output_shape(0))
```

Each task has a decoder in BCDL that turns those raw outputs into boxes,
keypoints, masks, disparity or text — see the
[Python API](https://github.com/ruisv/bcdl/blob/main/docs/API.md)
([中文](https://github.com/ruisv/bcdl/blob/main/docs/API.zh.md)).

## What to know before deploying

**Two calibration modes, and you must match the one you letterbox with.** `_crop`
was calibrated on centre-cropped pairs and `_int16` on resize-fitted ones; feed a
build the geometry it was not calibrated for and the disparity degrades quietly
rather than failing.

All-2D and feed-forward — no 3-D cost volume — which is exactly why it runs at
73 FPS here. Cost-volume stereo of comparable quality took ~40 s/frame on this
part and was abandoned.

## Licence

MIT on the code and the weights. One thing worth knowing rather than a term passed down: the release was distilled from FoundationStereo, whose NVIDIA licence is research-only. That is upstream's compliance question, but look at it before a commercial build.

**BCDL itself is Apache-2.0 and is unrelated to these terms** — it is a
general-purpose runtime that loads any `.hbm`. The licence above constrains
*these weights and this compiled artefact*.

The conversion recipe — ONNX export, calibration, `hb_compile` config and the
acceptance numbers — is public in
[**bcdl-model-zoo**](https://github.com/ruisv/bcdl-model-zoo), so this build can
be reproduced or retargeted rather than taken on trust.