medaugmentx 0.2.0

Clinically-aware medical image augmentation for AI training (MRI, CT, X-Ray, Tomosynthesis).

MedAugmentX

Clinically-aware medical image augmentation for AI training.

MedAugmentX is a purpose-built Python library for data augmentation of medical images. Unlike general-purpose libraries (torchvision, albumentations), it treats the unique properties of medical data — anisotropic 3D volumes, modality-specific artifacts, mask consistency, and clinical I/O — as first-class concerns.

Zero deep-learning dependencies. The core library requires only NumPy and SciPy. PyTorch, MONAI, and TorchIO interop are planned for Phase 3.

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Why MedAugmentX

Problem with general-purpose augmentation	What MedAugmentX does
Treats every image as 2D RGB	Native 3D volumes with anisotropic-aware ops
No MRI-specific noise or artifact models	Physics-based Rician noise, bias field, k-space corruption, ghosting
CT/DXR augmentation is generic brightness shift	Window/level variation, beam hardening, resolution simulation
Masks drift on complex transforms	Deterministic seeding; image and mask share the same random draw
No tomosynthesis support	Dedicated DBT module with slab-aware augmentations
DICOM/NIfTI I/O scattered across libraries	One loader, one MedVolume, vendor metadata preserved
Pipelines can't be saved or reloaded	Full JSON/YAML serialisation with round-trip reconstruction

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Install

# Core (NumPy + SciPy only)
pip install medaugmentx

# With DICOM/NIfTI I/O
pip install "medaugmentx[io]"

# With YAML serialisation support
pip install "medaugmentx[yaml]"

Verify the installation:

import medaugmentx
print(medaugmentx.__version__)   # 0.2.0

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Quick start

One-line preset

The fastest way to get started is a pre-built modality preset:

from medaugmentx.presets import mri_pipeline, ct_pipeline, dxr_pipeline, dbt_pipeline

pipeline = mri_pipeline(seed=42)
augmented = pipeline(vol)          # MedVolume in, MedVolume out

Four presets ship out of the box — see Preset pipelines below.

Build your own pipeline

import numpy as np
from medaugmentx import MedVolume, Compose, OneOf
from medaugmentx.transforms import (
    RandomAffine, ElasticDeform,
    BiasField, RicianNoise, GaussianNoise, GammaCorrection,
)

vol = MedVolume(
    image=np.random.rand(80, 256, 256).astype(np.float32),
    mask=np.zeros((80, 256, 256), dtype=np.uint8),
    spacing=(1.0, 0.7, 0.7),          # mm per axis (z, y, x)
    metadata={"modality": "MR"},
)

augment = Compose([
    RandomAffine(rotation=15, scale=(0.9, 1.1), p=0.7),
    ElasticDeform(alpha=(120, 120, 10), sigma=(10, 10, 3), p=0.5),
    BiasField(alpha=0.3, p=0.7),
    OneOf([
        RicianNoise(std=(0.005, 0.02)),   # MRI physical noise model
        GaussianNoise(std=0.015),          # simpler additive noise
    ], p=0.5),
    GammaCorrection(gamma=(0.8, 1.2), p=0.5),
], seed=42)

out = augment(vol)           # mask kept in sync automatically
print(out.image.shape, out.mask.shape)

Mask values are preserved exactly — spatial transforms use nearest-neighbour interpolation for the mask and the same random draw as the image.

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Preset pipelines

Ready-to-use Compose pipelines for common modalities. All presets are seeded, deterministic, and serialisable.

from medaugmentx.presets import mri_pipeline, ct_pipeline, dxr_pipeline, dbt_pipeline

mri  = mri_pipeline(seed=42)   # bias field, Rician noise, ghosting/k-space
ct   = ct_pipeline(seed=42)    # window/level, Gaussian noise, beam hardening
dxr  = dxr_pipeline(seed=42)  # blur, brightness/contrast, low-resolution sim
dbt  = dbt_pipeline(seed=42)  # slab shift, limited-angle blur, anisotropic elastic

Each preset is a starting point — tune the parameters or swap transforms for your dataset.

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Serialisation

Pipelines serialise to JSON (built-in) or YAML (optional PyYAML):

from medaugmentx.serialization import to_json, from_json

pipeline = mri_pipeline(seed=42)

# Save
json_str = to_json(pipeline)
with open("pipeline.json", "w") as f:
    f.write(json_str)

# Reload — exact same structure, ready to run
pipeline2 = from_json(open("pipeline.json").read())
out = pipeline2(vol)

Custom transforms can be added to the registry so they serialise too:

from medaugmentx.serialization import REGISTRY
REGISTRY["MyTransform"] = MyTransform

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Loading real volumes

from medaugmentx.io import load_dicom_series, load_nifti, save_nifti

vol_ct  = load_dicom_series("/path/to/study/CT_chest/")  # MedVolume
vol_mri = load_nifti("brain_t1.nii.gz")                   # MedVolume

augmented = ct_pipeline(seed=0)(vol_ct)
save_nifti(augmented, "ct_augmented.nii.gz")

Both loaders populate spacing and metadata (modality, vendor, DICOM tags) automatically.

Requires the io extra: pip install "medaugmentx[io]"

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What's available

Core

Component	Description
MedVolume	Container: image + optional mask + spacing + metadata
Transform	Abstract base — probability gating, seedable RNG, to_dict()
Compose	Sequential pipeline with deterministic child seeding
OneOf / SomeOf	Random selection from a set of transforms

Spatial transforms

Transform	What it does
RandomAffine	Rotation + scaling + translation, 2D/3D, axis-aware
RandomFlip	Per-axis flip with independent probability
AnatomicCrop	Foreground-biased random crop
ElasticDeform	Anisotropic B-spline elastic deformation

Intensity transforms

Transform	What it does
GaussianNoise	Additive zero-mean Gaussian noise
RicianNoise	MRI magnitude noise (physically correct for low-SNR regions)
GammaCorrection	Power-law contrast, normalisation-aware
BiasField	Smooth multiplicative field (MRI coil inhomogeneity)
WindowLevel	Random CT window/level shift (protocol variation)
BrightnessContrast	Additive brightness + multiplicative contrast
GaussianBlur	Isotropic Gaussian blur
SimulateLowResolution	Downsample + upsample (cross-site resolution variation)

Modality-specific — MRI

Transform	What it does
GhostingArtifact	Phase-encoding ghosting (shifted attenuated replica)
KSpaceDropout	Random k-space line zeroing with Gibbs ringing reconstruction

Modality-specific — CT

Transform	What it does
BeamHardening	Radially-symmetric cupping artifact

Modality-specific — Tomosynthesis (DBT)

Transform	What it does
SlabShift	Z-axis reconstruction-centre variation
LimitedAngleBlur	Arc-angle-dependent Z-only blur
SliceDropout	Random slice zeroing (robustness)
AnisotropicElastic	DBT-default elastic deformation

I/O

Helper	Description
load_dicom_series(path)	3D volume from a DICOM series directory
load_nifti(path)	MedVolume from .nii / .nii.gz
save_nifti(vol, path)	Write MedVolume to NIfTI

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Reproducibility

Every transform is seedable. Compose(..., seed=42) produces bit-identical output across runs and across machines (within a NumPy version):

a = Compose([...], seed=42)(vol)
b = Compose([...], seed=42)(vol)
assert np.array_equal(a.image, b.image)  # always passes

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Project status & roadmap

Phase	Status
1 — Core MVP	✅ Core data model, spatial/intensity transforms, DBT, DICOM/NIfTI I/O
2 — Modality artifacts & serialisation	✅ MRI (bias field, ghosting, k-space), CT (beam hardening), presets, JSON/YAML
3 — GPU backend, framework interop, v1.0	Planned

Detailed deliverables: docs/MILESTONES.md.

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Contributing

We welcome PRs — new transforms, vendor DICOM coverage, and bug reports with sample data are especially valuable. See CONTRIBUTING.md for the development setup, testing conventions, and the transform-authoring template.

License

MIT — see LICENSE.