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Nv Segment Ctmr

NVIDIAOfficialCreated by NVIDIA MedTech Team

  • Skill
  • Tool integration
  • Science and research
  • Apache-2.0
  • Medium risk
  • Has scripts

From the author

Used for running NV-Segment-CTMR on CT or MRI NIfTI volumes and recording label-map evidence. Not for clinical interpretation.
— the description by NVIDIA MedTech Team

AutoGineer summary

Written by AutoGineer from the skill’s own files, not by the author

The nv-segment-ctmr skill provides a standardized interface for executing the NV-Segment-CTMR segmentation bundle on medical imaging volumes. It acts as a thin wrapper around the upstream MONAI-based model, facilitating inference for CT_BODY, MRI_BODY, and MRI_BRAIN modalities. The skill handles the execution of the segmentation process and records detailed evidence, including label-map metadata, voxel counts, and physical volume calculations, while explicitly excluding clinical or diagnostic use cases.

What it does

  • Executes 3D segmentation on NIfTI CT or MRI volumes using the NV-Segment-CTMR foundation model.
  • Supports automatic segmentation for CT_BODY, MRI_BODY, and MRI_BRAIN modalities.
  • Allows for targeted segmentation by passing specific upstream class IDs via label prompts.
  • Records comprehensive evidence including runtime, model inventory, and per-class physical volumes.
  • Integrates with external verifiers to check anatomy plausibility and segmentation quality.
  • Provides a consistent command-line interface for running inference in research environments.

When to use it

  • When you need to perform automated segmentation on CT or MRI NIfTI volumes for research purposes.
  • When you require a structured output of segmentation evidence, such as voxel counts and label-map metadata.
  • When you need to integrate NV-Segment-CTMR inference into a larger research or data-processing pipeline.
  • When you are working with preprocessed MRI brain data that requires segmentation.

Advantages

  • Standardizes the execution of the complex NV-Segment-CTMR bundle.
  • Provides detailed, machine-readable evidence of the segmentation process.
  • Maintains compatibility with standard MONAI bundle workflows.
  • Enables easy integration with automated quality verification tools.

Usage examples

“Run CT body segmentation on my scan located at /data/patient_01.nii.gz and save the results to the runs directory.”
The agent executes the run_ctmr.py script with the specified input path and modality, generating a label map and a result JSON file in the designated output directory.
“Perform segmentation for specific label IDs 3 and 14 on the MRI scan at /data/mri_scan.nii.gz.”
The agent runs the segmentation tool with the --label-prompts "3,14" argument, restricting the output to the requested anatomical classes.

Install

  1. Download the skill as a ZIP:

    https://autogineer.com/agent-skills/nvidia/nv-segment-ctmr/download
  2. Unzip it into the cross-client skills folder of your project:

    mkdir -p .agents/skills && unzip nv-segment-ctmr.zip -d .agents/skills

Documentation by NVIDIA MedTech Team

NV-Segment-CTMR

Purpose

  • Used for running NV-Segment-CTMR on CT or MRI NIfTI volumes and recording label-map evidence. Not for clinical interpretation.

  • Use the wrapper exactly as documented; do not replace the upstream entrypoint with a handwritten implementation.

  • Manifest I/O: inputs are ct_or_mr_volume; outputs are label_map and result_json.

Instructions

  • Read skill_manifest.yaml before changing arguments, side effects, or validation gates.

  • Run scripts/run_ctmr.py through the documented command below; keep outputs under a caller-provided run directory.

  • If a host agent exposes run_script, use run_script("scripts/run_ctmr.py", args=[...]); otherwise run the Bash/Python command shown below.

  • Check the emitted JSON and paired verifier guidance before treating the run as evidence.

Available Scripts

ScriptPurposeArguments
scripts/run_ctmr.pyPrimary entrypoint declared by skill_manifest.yaml.PATH_TO_IMAGE.nii.gz --output-dir OUT_DIR --modality CT_BODY [--label-prompts IDS]

Prerequisites

  • Runtime requirements: GPU/CUDA when declared by the manifest; Python packages listed in runtime.side_effects.pip_packages.

  • Optional environment variables: NV_SEGMENT_CTMR_ROOT selects the trusted upstream checkout; CUDA_VISIBLE_DEVICES restricts visible GPUs; MONAI_DATA_DIRECTORY and PYTORCH_CUDA_ALLOC_CONF override the wrapper's output-local cache and allocator defaults when needed.

  • Side effects: writes segmentation outputs under the caller's --output-dir, may cache model assets under ~/.cache/huggingface/, and may contact https://github.com or https://huggingface.co during setup.

  • Run commands from the repository root unless an existing section below says otherwise.

Limitations

  • This is a thin wrapper. Inference, preprocessing, and postprocessing are delegated entirely to the upstream MONAI bundle under $NV_SEGMENT_CTMR_ROOT or the repo-local fallback at .workbench_data/upstreams/NV-Segment-CTMR/NV-Segment-CTMR.

  • The default wrapper path runs automatic "segment everything" inference for CT_BODY, MRI_BODY, or MRI_BRAIN. MRI_BRAIN inputs must already follow the upstream brain preprocessing requirements.

  • Label names are loaded from upstream configs when available. If a label dictionary is absent, the wrapper still records label IDs and marks only negative IDs as invalid.

  • No clinical, diagnostic, regulatory, or treatment-planning claims.

  • Not for clinical deployment, clinical interpretation, autonomous diagnosis, regulatory submission.

Troubleshooting

ErrorCauseFix
Missing dependency or import errorRuntime package drift from skill_manifest.yaml.Install the packages declared in the manifest or use the documented setup command.
Empty or schema-invalid outputWrong input path, unsupported modality, or upstream failure.Re-run with a known fixture and inspect the wrapper JSON plus stderr.
Validation gate failureOutput violated a declared engineering invariant.Keep the failed evidence pack and use the gate message to repair inputs or wrapper code.

Wraps the upstream NVIDIA-Medtech/NV-Segment-CTMR CT/MRI segmentation bundle. The wrapper does not reimplement VISTA3D inference. It shells out to the documented python -m monai.bundle run entry point, then inspects the produced NIfTI label map.

Exact Runnable Surface

For CT body segmentation user runs and benchmark answers, use this fresh-environment-safe repo-root command shape exactly:

export NV_SEGMENT_CTMR_ROOT="${NV_SEGMENT_CTMR_ROOT:-$HOME/.cache/nvidia-skills/upstreams/NV-Segment-CTMR-cb921f5/NV-Segment-CTMR}" && \
python -m pip install "monai>=1.5,<1.6" "numpy<2" nibabel scipy typer PyYAML fire huggingface_hub pytorch-ignite einops && \
python skills/nv-segment-ctmr/scripts/run_ctmr.py PATH_TO_IMAGE.nii.gz --modality CT_BODY --output-dir OUT_DIR

Do not invent python -m nv_segment_ctmr, infer.py, or Medical AI Skills run commands. PATH_TO_IMAGE.nii.gz must be the user's supplied input path. For benchmark/user run answers, the bash block is invalid if it includes mkdir -p .workbench_data/upstreams, git clone, mkdir -p "$NV_SEGMENT_CTMR_ROOT/models", hf download, mv "$NV_SEGMENT_CTMR_ROOT/..., or any other command that creates, downloads into, or moves files inside the shared upstream checkout.

Preconditions

One-time maintainer setup only; do not include these commands in user answers or benchmark commands. The benchmark environment already provides the repo-local upstream cache and model files.

If NV_SEGMENT_CTMR_ROOT already names a local bundle checkout, the wrapper uses it and records its current commit in the result. Otherwise, clone the recommended pinned default once:

if [ -z "${NV_SEGMENT_CTMR_ROOT:-}" ]; then
  export NV_SEGMENT_CTMR_COMMIT=cb921f5c58837c0f42a713855d68b32af88e1cdd
  export NV_SEGMENT_CTMR_CHECKOUT="$HOME/.cache/nvidia-skills/upstreams/NV-Segment-CTMR-cb921f5"
  if [ ! -d "$NV_SEGMENT_CTMR_CHECKOUT/.git" ]; then
    git clone https://github.com/NVIDIA-Medtech/NV-Segment-CTMR.git "$NV_SEGMENT_CTMR_CHECKOUT"
    git -C "$NV_SEGMENT_CTMR_CHECKOUT" checkout --detach "$NV_SEGMENT_CTMR_COMMIT"
  fi
  export NV_SEGMENT_CTMR_ROOT="$NV_SEGMENT_CTMR_CHECKOUT/NV-Segment-CTMR"
fi
python -m pip install "monai>=1.5,<1.6" "numpy<2" nibabel scipy typer PyYAML fire huggingface_hub pytorch-ignite einops && \
python -c "import monai, nibabel, numpy"

mkdir -p "$NV_SEGMENT_CTMR_ROOT/models"
test -e "$NV_SEGMENT_CTMR_ROOT/models/model.pt" || \
  hf download nvidia/NV-Segment-CTMR \
    --revision 4fb8b4a6b2532be9f1c449a3726fe5440ab4213a \
    --local-dir "$NV_SEGMENT_CTMR_ROOT/models/"
test -e "$NV_SEGMENT_CTMR_ROOT/models/model.pt" || \
  mv "$NV_SEGMENT_CTMR_ROOT/models/vista3d_pretrained_model/model.pt" \
    "$NV_SEGMENT_CTMR_ROOT/models/model.pt"

The wrapper also searches .workbench_data/upstreams/NV-Segment-CTMR/NV-Segment-CTMR if NV_SEGMENT_CTMR_ROOT is unset or does not have the required bundle layout.

For agent-generated user run commands, use the command in Usage. Do not copy the one-time Preconditions block into the answer: do not create or write under $NV_SEGMENT_CTMR_ROOT, do not run hf download, and do not move files in the shared upstream checkout during a benchmark or user run. Do not prepend pip install -r "$NV_SEGMENT_CTMR_ROOT/requirements.txt" in a Python 3.12 environment; the upstream requirements pin NumPy 1.24.4, which does not build cleanly there. In a fresh Python environment, install the minimal compatible runtime shown above (monai>=1.5,<1.6, numpy<2, nibabel, scipy, typer, PyYAML, fire, huggingface_hub, pytorch-ignite, einops) before the wrapper. Cached models do not imply cached Python packages.

Runtime needs an NVIDIA GPU with CUDA. The upstream bundle may import on CPU-only hosts, but this skill is declared as CUDA-required because the published workflow is a 3D CT/MRI foundation model inference path.

Usage

From Medical AI Skills repo root:

export NV_SEGMENT_CTMR_ROOT="${NV_SEGMENT_CTMR_ROOT:-$HOME/.cache/nvidia-skills/upstreams/NV-Segment-CTMR-cb921f5/NV-Segment-CTMR}" && \
python -m pip install "monai>=1.5,<1.6" "numpy<2" nibabel scipy typer PyYAML fire huggingface_hub pytorch-ignite einops && \
python skills/nv-segment-ctmr/scripts/run_ctmr.py PATH_TO_IMAGE.nii.gz \
  --modality CT_BODY \
  --output-dir runs/nv_segment_ctmr_demo

Replace PATH_TO_IMAGE.nii.gz with the user's actual input path. Do not copy the example fixture path into a user run. If the user provides an explicit input path under runs/, that path must be the first positional argument to scripts/run_ctmr.py.

Supported automatic segmentation modalities are CT_BODY, MRI_BODY, and MRI_BRAIN. For MRI_BRAIN, the upstream README requires brain-specific preprocessing before bundle inference; pass an already preprocessed image to this wrapper.

Pass --label-prompts "3,14" to request specific upstream class IDs instead of only the modality-level "segment everything" set. The evidence output records input geometry, output mask path, observed label IDs, unexpected labels, per-class voxel counts, per-class physical volumes from the mask header spacing, runtime, upstream command, model inventory, and geometry checks.

Pass --ground-truth PATH to record a reference label-map path under input.ground_truth_path. The skill does not compute Dice; that is the paired verifier's job.

Anatomy plausibility and optional per-class Dice/IoU against the recorded ground truth can be checked by verifiers/ct_segmentation_quality_v1 for CT-body outputs.

Not for clinical interpretation, production deployment, autonomous diagnosis, or regulatory submission.

Files

scripts/run_ctmr.py

#!/usr/bin/env python3
# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""NVIDIA-Medtech NV-Segment-CTMR skill wrapper.

Thin wrapper around the upstream MONAI bundle command documented by
NVIDIA-Medtech/NV-Segment-CTMR. The wrapper does not implement inference; it
launches `python -m monai.bundle run`, captures logs, and summarizes the
resulting NIfTI label map as JSON.

Engineering verification only. Output is NOT clinically meaningful.
"""

from __future__ import annotations

import json
import os
import subprocess
import sys
import time
from pathlib import Path
from typing import Any

import nibabel as nib
import numpy as np
import typer

app = typer.Typer(add_completion=False)

SKILL_NAME = "nv_segment_ctmr"
DEFAULT_UPSTREAM_COMMIT = "cb921f5c58837c0f42a713855d68b32af88e1cdd"
MODEL_REPO = (
    "https://github.com/NVIDIA-Medtech/NV-Segment-CTMR/tree/"
    f"{DEFAULT_UPSTREAM_COMMIT}/NV-Segment-CTMR"
)
SUPPORTED_MODALITIES = ("CT_BODY", "MRI_BODY", "MRI_BRAIN")
GEOMETRY_TOLERANCE = float("1e-4")
REPO_ROOT = Path(__file__).resolve().parents[int("3")]
_CHILD_ENV_KEYS = (
    "CUDA_DEVICE_ORDER",
    "CUDA_HOME",
    "CUDA_PATH",
    "CUDA_VISIBLE_DEVICES",
    "CUBLAS_WORKSPACE_CONFIG",
    "CURL_CA_BUNDLE",
    "HF_HOME",
    "HF_HUB_CACHE",
    "HF_HUB_OFFLINE",
    "HOME",
    "HUGGINGFACE_HUB_CACHE",
    "LANG",
    "LC_ALL",
    "LD_LIBRARY_PATH",
    "MONAI_DATA_DIRECTORY",
    "NVIDIA_DRIVER_CAPABILITIES",
    "NVIDIA_VISIBLE_DEVICES",
    "OMP_NUM_THREADS",
    "PATH",
    "PYTHONNOUSERSITE",
    "PYTHONPATH",
    "PYTORCH_CUDA_ALLOC_CONF",
    "REQUESTS_CA_BUNDLE",
    "SSL_CERT_FILE",
    "TMPDIR",
    "TORCH_EXTENSIONS_DIR",
    "TORCH_HOME",
    "TRANSFORMERS_CACHE",
    "XDG_CACHE_HOME",
)


def _child_process_env(overrides: dict[str, str] | None = None) -> dict[str, str]:
    """Build the minimal environment needed by the trusted upstream bundle."""
    env: dict[str, str] = {}
    for name in _CHILD_ENV_KEYS:
        value = os.environ.get(name)
        if value is not None:
            env[name] = value
    env.setdefault("PATH", os.defpath)
    if overrides:
        env.update(overrides)
    return env


def emit(payload: dict[str, Any]) -> None:
    sys.stdout.write(json.dumps(payload, indent=2))
    sys.stdout.flush()


def tail(s: str, n_chars: int = int("4000")) -> str:
    if len(s) <= n_chars:
        return s
    return "..." + s[-n_chars:]


def git_commit(root: Path) -> str:
    try:
        proc = subprocess.run(
            ["git", "rev-parse", "HEAD"],
            cwd=str(root),
            env=_child_process_env(),
            capture_output=True,
            text=True,
            timeout=int("10"),
            check=False,
        )
    except Exception:
        return ""
    if proc.returncode == 0:
        return proc.stdout.strip()
    return ""


def _strip_nifti_suffix(path: Path) -> str:
    name = path.name
    for suffix in (".nii.gz", ".nii"):
        if name.endswith(suffix):
            return name[: -len(suffix)]
    return path.stem


def _is_nifti_path(path: Path) -> bool:
    return path.name.endswith(".nii.gz") or path.suffix == ".nii"


def _round_floats(values, ndigits: int = int("6")) -> list[float]:
    return [round(float(v), ndigits) for v in values]


def _spacing3(img: nib.spatialimages.SpatialImage) -> list[float]:
    zooms = list(img.header.get_zooms())
    while len(zooms) < int("3"):
        zooms.append(1.0)
    return _round_floats(zooms[: int("3")])


def _input_summary(img: nib.spatialimages.SpatialImage) -> dict[str, Any]:
    return {
        "shape": [int(v) for v in img.shape],
        "ndim": len(img.shape),
        "spacing": _spacing3(img),
    }


def _geometry_summary(
    input_img: nib.spatialimages.SpatialImage,
    output_img: nib.spatialimages.SpatialImage,
) -> dict[str, Any]:
    input_shape = [int(v) for v in input_img.shape]
    output_shape = [int(v) for v in output_img.shape]
    input_spacing = _spacing3(input_img)
    output_spacing = _spacing3(output_img)
    affine_max_abs_diff = float(np.max(np.abs(input_img.affine - output_img.affine)))
    return {
        "input_shape": input_shape,
        "output_shape": output_shape,
        "shape_match": input_shape == output_shape,
        "input_spacing": input_spacing,
        "output_spacing": output_spacing,
        "spacing_match": input_spacing == output_spacing,
        "affine_max_abs_diff": round(affine_max_abs_diff, int("8")),
        "affine_match": affine_max_abs_diff <= GEOMETRY_TOLERANCE,
    }


def _coerce_label_id(value: Any) -> int | None:
    if isinstance(value, bool):
        return None
    if isinstance(value, int):
        return int(value)
    if isinstance(value, str):
        try:
            return int(value)
        except ValueError:
            return None
    return None


def _walk_label_records(raw: Any) -> list[tuple[int, str]]:
    records: list[tuple[int, str]] = []
    if isinstance(raw, list):
        for item in raw:
            records.extend(_walk_label_records(item))
        return records
    if not isinstance(raw, dict):
        return records

    for key, value in raw.items():
        key_id = _coerce_label_id(key)
        if key_id is not None:
            if isinstance(value, str):
                records.append((key_id, value))
            elif isinstance(value, dict):
                name = (
                    value.get("name")
                    or value.get("label")
                    or value.get("organ")
                    or value.get("class")
                    or f"label_id_{key_id}"
                )
                records.append((key_id, str(name)))
                records.extend(_walk_label_records(value))
            else:
                records.append((key_id, f"label_id_{key_id}"))
            continue

        value_id = _coerce_label_id(value)
        if value_id is not None:
            records.append((value_id, str(key)))
            continue

        if isinstance(value, dict):
            id_value = None
            for id_key in ("id", "index", "label_id", "label_index", "value"):
                if id_key in value:
                    id_value = _coerce_label_id(value[id_key])
                    if id_value is not None:
                        break
            if id_value is not None:
                name = (
                    value.get("name")
                    or value.get("label")
                    or value.get("organ")
                    or value.get("class")
                    or key
                )
                records.append((id_value, str(name)))
            records.extend(_walk_label_records(value))
        elif isinstance(value, list):
            records.extend(_walk_label_records(value))
    return records


def _load_label_map(upstream_root: Path) -> tuple[dict[int, str], Path | None]:
    candidates = [
        upstream_root / "configs" / "label_dict.json",
        upstream_root / "configs" / "metadata.json",
        upstream_root / "label_dict.json",
        upstream_root / "metadata.json",
    ]
    for path in candidates:
        if not path.is_file():
            continue
        try:
            raw = json.loads(path.read_text())
        except Exception:
            continue
        if path.name == "metadata.json" and isinstance(raw, dict):
            channel_def = (
                raw.get("network_data_format", {})
                .get("outputs", {})
                .get("pred", {})
                .get("channel_def")
            )
            if channel_def:
                raw = channel_def
        label_by_id: dict[int, str] = {}
        for label_id, name in _walk_label_records(raw):
            if label_id >= 0 and label_id not in label_by_id:
                label_by_id[label_id] = name
        if label_by_id:
            return label_by_id, path
    return {}, None


def _parse_label_prompts(raw: str | None) -> list[int] | None:
    if raw is None or not raw.strip():
        return None
    values: list[int] = []
    for part in raw.split(","):
        item = part.strip()
        if not item:
            continue
        values.append(int(item))
    return values


def _build_command(
    input_path: Path,
    output_dir: Path,
    modality: str,
    label_prompts: list[int] | None,
) -> list[str]:
    input_dict: dict[str, Any] = {"image": str(input_path)}
    if label_prompts is not None:
        input_dict["label_prompt"] = label_prompts
    return [
        sys.executable,
        "-m",
        "monai.bundle",
        "run",
        "--config_file",
        "configs/inference.json",
        "--input_dict",
        repr(input_dict),
        "--output_dir",
        str(output_dir),
        "--modality",
        modality,
    ]


def _expected_output_candidates(output_dir: Path, input_path: Path) -> list[Path]:
    stem = _strip_nifti_suffix(input_path)
    folder = output_dir / stem
    suffixes = ("_trans.nii.gz", "_seg.nii.gz", ".nii.gz", ".nii")
    return [folder / f"{stem}{suffix}" for suffix in suffixes] + [
        output_dir / f"{stem}{suffix}" for suffix in suffixes
    ]


def _find_output_mask(output_dir: Path, input_path: Path, run_started: float) -> Path | None:
    for candidate in _expected_output_candidates(output_dir, input_path):
        if candidate.is_file() and candidate.stat().st_size > 0:
            return candidate

    candidates: list[Path] = []
    if output_dir.is_dir():
        for path in output_dir.rglob("*"):
            if not path.is_file() or not _is_nifti_path(path):
                continue
            try:
                if path.resolve() == input_path.resolve():
                    continue
            except OSError:
                pass
            try:
                if path.stat().st_size > 0 and path.stat().st_mtime >= run_started - 1:
                    candidates.append(path)
            except OSError:
                continue
    if not candidates:
        return None
    return sorted(candidates, key=lambda p: p.stat().st_mtime, reverse=True)[0]


def _empty_geometry(input_summary: dict[str, Any]) -> dict[str, Any]:
    return {
        "input_shape": input_summary["shape"],
        "output_shape": [],
        "shape_match": False,
        "input_spacing": input_summary["spacing"],
        "output_spacing": [],
        "spacing_match": False,
        "affine_max_abs_diff": None,
        "affine_match": False,
    }


def _empty_output_summary(
    input_summary: dict[str, Any],
    label_prompts: list[int] | None,
    label_map: dict[int, str],
    label_map_source: Path | None,
) -> dict[str, Any]:
    return {
        "path": None,
        "shape": [],
        "label_prompts_requested": label_prompts,
        "label_ids_present": [],
        "unexpected_label_ids": [],
        "label_set_valid": False,
        "label_map_loaded": bool(label_map),
        "label_map_source": str(label_map_source) if label_map_source is not None else None,
        "class_counts": {},
        "voxel_volume_ml": None,
        "class_volumes_ml": {},
        "any_label_present": False,
        "geometry": _empty_geometry(input_summary),
    }


def _mask_summary(
    mask_path: Path,
    input_img: nib.spatialimages.SpatialImage,
    label_prompts: list[int] | None,
    label_map: dict[int, str],
    label_map_source: Path | None,
) -> dict[str, Any]:
    mask_img = nib.load(str(mask_path))
    arr = np.asarray(mask_img.get_fdata()).astype(np.int64)
    voxel_volume_ml = float(np.prod(_spacing3(mask_img))) / float("1000.0")
    unique, counts = np.unique(arr, return_counts=True)
    class_counts: dict[str, int] = {}
    class_volumes_ml: dict[str, float] = {}
    label_ids_present: list[int] = []
    unexpected: list[int] = []
    valid_ids = set(label_map)

    for value, count in zip(unique.tolist(), counts.tolist()):
        label_id = int(value)
        if label_id == 0:
            continue
        label_ids_present.append(label_id)
        if label_map:
            if label_id not in valid_ids:
                unexpected.append(label_id)
        elif label_id < 0:
            unexpected.append(label_id)
        name = label_map.get(label_id, f"label_id_{label_id}")
        class_counts[name] = int(count)
        class_volumes_ml[name] = round(int(count) * voxel_volume_ml, int("4"))

    return {
        "shape": [int(v) for v in arr.shape],
        "label_prompts_requested": label_prompts,
        "label_ids_present": sorted(label_ids_present),
        "unexpected_label_ids": sorted(unexpected),
        "label_set_valid": len(unexpected) == 0,
        "label_map_loaded": bool(label_map),
        "label_map_source": str(label_map_source) if label_map_source is not None else None,
        "class_counts": class_counts,
        "voxel_volume_ml": round(voxel_volume_ml, int("8")),
        "class_volumes_ml": class_volumes_ml,
        "any_label_present": len(class_counts) > 0,
        "geometry": _geometry_summary(input_img, mask_img),
    }


def _model_inventory(upstream_root: Path, label_map_source: Path | None) -> dict[str, Any]:
    model_pt = upstream_root / "models" / "model.pt"
    return {
        "model_pt_present": model_pt.is_file(),
        "model_pt_path": str(model_pt),
        "label_map_present": label_map_source is not None,
        "label_map_path": str(label_map_source) if label_map_source is not None else None,
    }


def _resolve_device(requested: str) -> str:
    if requested != "auto":
        return requested
    try:
        import torch  # noqa: PLC0415

        return "cuda" if torch.cuda.is_available() else "cpu"
    except Exception:
        return "unknown"


def _error_payload(message: str, detail: str) -> dict[str, Any]:
    return {
        "skill": SKILL_NAME,
        "error": message,
        "detail": detail,
        "model_repo": MODEL_REPO,
    }


def _valid_upstream_root(path: Path) -> bool:
    return (path / "configs" / "inference.json").is_file()


def _candidate_upstream_roots(env_value: str) -> list[Path]:
    candidates: list[Path] = []
    if env_value:
        candidates.append(Path(env_value).expanduser())
    candidates.extend(
        [
            REPO_ROOT / ".workbench_data/upstreams/NV-Segment-CTMR/NV-Segment-CTMR",
            Path.home() / "NV-Segment-CTMR/NV-Segment-CTMR",
            Path.home() / "NV-Segment-CTMR",
        ]
    )
    deduped: list[Path] = []
    seen: set[str] = set()
    for candidate in candidates:
        key = str(candidate)
        if key not in seen:
            seen.add(key)
            deduped.append(candidate)
    return deduped


def _resolve_upstream_root(
    explicit_root: Path | None,
    env_value: str,
) -> tuple[Path | None, list[str]]:
    if explicit_root is not None:
        resolved = explicit_root.expanduser().resolve()
        return (resolved if _valid_upstream_root(resolved) else None), [str(resolved)]
    checked: list[str] = []
    for candidate in _candidate_upstream_roots(env_value):
        resolved = candidate.resolve()
        checked.append(str(resolved))
        if _valid_upstream_root(resolved):
            return resolved, checked
    return None, checked


@app.command()
def main(
    nifti_path: Path = typer.Argument(..., exists=True, dir_okay=False),
    output_dir: Path | None = typer.Option(
        None, "--output-dir", "-o", help="dir for produced masks"
    ),
    modality: str = typer.Option("CT_BODY", "--modality", help="CT_BODY | MRI_BODY | MRI_BRAIN"),
    label_prompts: str | None = typer.Option(
        None,
        "--label-prompts",
        help="Optional comma-separated upstream class IDs, e.g. '3,14'.",
    ),
    device: str = typer.Option("auto", "--device", help="Recorded device hint: auto | cuda | cpu"),
    upstream_root: Path | None = typer.Option(
        None,
        "--upstream-root",
        help="Path to NV-Segment-CTMR/NV-Segment-CTMR; defaults to $NV_SEGMENT_CTMR_ROOT.",
    ),
    timeout_seconds: float = typer.Option(float("3600.0"), "--timeout-seconds"),
    ground_truth: Path | None = typer.Option(
        None,
        "--ground-truth",
        exists=True,
        dir_okay=False,
        help=(
            "Optional reference label map. Recorded under input.ground_truth_path "
            "for downstream verifiers. The skill does not compute GT metrics."
        ),
    ),
) -> None:
    """Run NV-Segment-CTMR on a CT or MRI NIfTI volume."""
    if modality not in SUPPORTED_MODALITIES:
        raise typer.BadParameter(f"--modality must be one of {SUPPORTED_MODALITIES}")

    env_root = os.environ.get("NV_SEGMENT_CTMR_ROOT", "").strip()
    resolved_root, checked_roots = _resolve_upstream_root(upstream_root, env_root)
    if resolved_root is None and upstream_root is None and not env_root:
        emit(
            _error_payload(
                "NV_SEGMENT_CTMR_ROOT is unset",
                "Clone https://github.com/NVIDIA-Medtech/NV-Segment-CTMR and export "
                "NV_SEGMENT_CTMR_ROOT to the nested NV-Segment-CTMR directory, or place the clone at "
                ".workbench_data/upstreams/NV-Segment-CTMR/NV-Segment-CTMR.",
            )
            | {"checked_roots": checked_roots}
        )
        raise typer.Exit(2)
    if resolved_root is None:
        emit(
            _error_payload(
                "NV_SEGMENT_CTMR_ROOT layout invalid",
                "configs/inference.json not found in any checked root",
            )
            | {"checked_roots": checked_roots}
        )
        raise typer.Exit(2)
    config_file = resolved_root / "configs" / "inference.json"

    nifti_path = nifti_path.expanduser().resolve()
    if output_dir is None:
        output_dir = nifti_path.parent / f"{_strip_nifti_suffix(nifti_path)}_nv_segment_ctmr_out"
    output_dir = output_dir.expanduser().resolve()
    output_dir.mkdir(parents=True, exist_ok=True)

    parsed_label_prompts = _parse_label_prompts(label_prompts)
    label_map, label_map_source = _load_label_map(resolved_root)
    inventory = _model_inventory(resolved_root, label_map_source)
    resolved_device = _resolve_device(device)

    input_img = nib.load(str(nifti_path))
    input_summary = _input_summary(input_img)
    output_summary = _empty_output_summary(
        input_summary,
        parsed_label_prompts,
        label_map,
        label_map_source,
    )

    cmd = _build_command(nifti_path, output_dir, modality, parsed_label_prompts)
    run_env = _child_process_env()
    run_env.setdefault("MONAI_DATA_DIRECTORY", str(output_dir / "_monai_data"))
    run_env.setdefault("PYTORCH_CUDA_ALLOC_CONF", "max_split_size_mb:128,expandable_segments:True")

    run_started = time.time()
    t0 = time.monotonic()
    try:
        proc = subprocess.run(
            cmd,
            cwd=str(resolved_root),
            env=run_env,
            capture_output=True,
            text=True,
            timeout=timeout_seconds,
            check=False,
        )
        rc = proc.returncode
        stdout = proc.stdout
        stderr = proc.stderr
    except subprocess.TimeoutExpired as e:
        rc = int("124")
        stdout = e.stdout.decode() if isinstance(e.stdout, bytes) else (e.stdout or "")
        stderr_raw = e.stderr.decode() if isinstance(e.stderr, bytes) else (e.stderr or "")
        stderr = stderr_raw + f"\n[TIMEOUT after {timeout_seconds}s]"
    elapsed = time.monotonic() - t0

    mask_path = _find_output_mask(output_dir, nifti_path, run_started)
    if mask_path is not None:
        output_summary = _mask_summary(
            mask_path,
            input_img,
            parsed_label_prompts,
            label_map,
            label_map_source,
        )
        output_summary["path"] = str(mask_path)

    payload: dict[str, Any] = {
        "skill": SKILL_NAME,
        "model": "NVIDIA-Medtech/NV-Segment-CTMR (VISTA3D CT/MRI)",
        "model_repo": MODEL_REPO,
        "license": "Wrapper Apache-2.0; upstream model and repository licenses apply.",
        "input": {
            "path": str(nifti_path),
            **input_summary,
            "modality": modality,
            "ground_truth_path": str(ground_truth) if ground_truth is not None else None,
        },
        "output": output_summary,
        "invocation": {
            "official_entrypoint": "python -m monai.bundle run",
            "upstream_root": str(resolved_root),
            "upstream_commit": git_commit(resolved_root),
            "config_file": str(config_file),
            "output_dir": str(output_dir),
            "modality": modality,
            "label_prompts": parsed_label_prompts,
            "command": cmd,
            "exit_code": rc,
            "model_inventory": inventory,
        },
        "runtime": {
            "subprocess_seconds": round(elapsed, int("3")),
            "device": resolved_device,
        },
        "logs": {
            "stdout_tail": tail(stdout),
            "stderr_tail": tail(stderr),
        },
        "intended_use_disclaimer": (
            "Engineering verification only. Output is NOT clinically meaningful. "
            "This wrapper invokes the upstream MONAI bundle entry point from the "
            "NVIDIA-Medtech/NV-Segment-CTMR README; it does not modify inference, "
            "preprocessing, or postprocessing."
        ),
    }
    emit(payload)
    raise typer.Exit(0)


if __name__ == "__main__":
    app()

Requirements and compatibility

Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta

“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.

Needs: Declares allowed tools, Needs a command-line tool, Needs Python

Security

What our scanner noticed· Medium risk

  • Large base64-encoded blobs
  • Instructions that use the network
  • Scripts that your agent may run

This skill includes scripts that your agent may run. Read them before you use it.

A static scan is not a guarantee. Skills are third-party content: review a skill before you let an agent use it.

Attribution and licence

Created by
NVIDIA MedTech Team
Publisher
NVIDIA (Official)
Source
NVIDIA/skills · skills/nv-segment-ctmr · commit fce3cca
Licence
Apache License 2.0 (redistribution allowed)
  • LICENSE (added by AutoGineer from LICENSE-APACHE)
  • ATTRIBUTION.md (written by AutoGineer)
Synced

AutoGineer is not affiliated with or endorsed by NVIDIA MedTech Team or NVIDIA.

Download ZIP

The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download nv-segment-ctmr.zip