LocateAnything-3B — MLX nvfp4 (for Krill)

A mixed-precision nvfp4 MLX build of nvidia/LocateAnything-3B, the NVIDIA visual-grounding VLM that locates anything in an image as bounding boxes (<box><x1><y1><x2><y2></box>, coordinates normalized to 0–1000). Runs natively on Apple Silicon via Krill — no Python, no PyTorch.

Why this build

  • Complete VLM, quantized end-to-end for MLX. The MoonViT (Kimi-VL) native-resolution vision tower is included and kept at full precision; only the Qwen2.5-3B text decoder is quantized, so grounding accuracy is preserved.
  • Grounding parity with bf16. On a synthetic check, boxes are identical to the bf16 source (e.g. a red rectangle at true 125/125/375/375 → 125/125/376/377).
  • Small and fast. ~3.1 GB (vs 7.8 GB bf16); ~48 tok/s decode, ~1.1 s time-to-first-box on an M-series Mac — fits any 16 GB machine with room to spare.
  • Native Krill runtime. Custom Swift+MLX MoonViT tower + connector, logit-parity-verified against the NVIDIA reference.

Quantization

Mixed precision produced by krill quantize --mode nvfp4:

  • Base: nvfp4 (4-bit, group 16) on the Qwen2.5-3B text Linears + embeddings.
  • Protected: 8-bit affine (group 64) on every o_proj and down_proj (quality).
  • MoonViT vision tower + mlp1 connector: fp (not quantized).

Usage (Krill)

# by alias (ships with Krill):
krill run locateanything-3b "Locate the red car." --image street.jpg

# or directly from this repo:
krill run srv-sngh/LocateAnything-3B-mlx-nvfp4 "Detect all people." --image crowd.jpg

Output is grounding text with boxes, e.g. <ref>the red car</ref><box><612><448><770><690></box>. Coordinates are 0–1000; scale by the image width/height to get pixels.

License & attribution

This is a derivative work of nvidia/LocateAnything-3B and is distributed under the same NVIDIA License (see LICENSE). Use is limited to non-commercial research or evaluation purposes only (NVIDIA and its affiliates excepted). The base model builds on Qwen2.5 (Qwen Research License) and MoonViT (MIT). Please cite and follow NVIDIA's original terms.

Downloads last month
45
Safetensors
Model size
1B params
Tensor type
U8
·
U32
·
F16
·
MLX
Hardware compatibility
Log In to add your hardware

4-bit

Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for srv-sngh/LocateAnything-3B-mlx-nvfp4

Base model

Qwen/Qwen2.5-3B
Quantized
(20)
this model