---

name: image-core description: "Work with SimpleITK Image objects, spatial metadata, pixel/component types, physical coordinates, and NumPy array conversion." disable-model-invocation: true metadata: disco-role: operating license: Apache 2.0

SimpleITK Image Core

Use this sub-skill when a task involves constructing or inspecting sitk.Image objects, preserving origin/spacing/direction, converting between index and physical coordinates, reading or writing individual pixels, diagnosing pixel/component ids, or bridging images to NumPy arrays.

Start Here

• Read references/image-model.md for the SimpleITK physical image model, spatial metadata, coordinate conversions, pixel/component categories, metadata dictionary basics, and validation checks.
• Read references/numpy-bridge.md for sitk.GetArrayFromImage, sitk.GetArrayViewFromImage, sitk.GetImageFromArray, reversed shape order, vector image component axes, dtype mapping, and metadata preservation after array processing.
• Read references/api-reference.md for concise verified constructor patterns, image methods, pixel inspection APIs, NumPy bridge behavior, and copy/view notes.
• Read references/troubleshooting.md when debugging metadata loss, reversed NumPy shapes, read-only array views, unsupported dtypes, wrong isVector choices, component mismatches, direction errors, or out-of-bounds indices.
• Run scripts/inspect_image_metadata.py to print JSON metadata for a readable image file or a deterministic built-in demo image from any current working directory.

Quick Routing

• For ReadImage, WriteImage, registered ImageIOs, DICOM tags, series discovery, file formats, or dataset examples, route to ../io-and-data/SKILL.md.
• For smoothing, thresholding, morphology, connected components, segmentation, measurements, or label workflows beyond basic pixel/type inspection, route to ../filtering-segmentation/SKILL.md.
• For registration, resampling, transforms as processing objects, interpolators, displacement fields, or coordinate-frame alignment workflows, route to ../registration-transforms/SKILL.md.
• For source builds, wrapping internals, optional elastix/transformix availability, packaging, or compiled feature differences, route to ../builds-and-wrapping/SKILL.md.

Essential Rules

• Import the public package as import SimpleITK as sitk; the Python distribution name is simpleitk.
• Treat an Image as a pixel buffer plus physical geometry. Preserve GetOrigin(), GetSpacing(), and GetDirection() whenever replacing pixels or rebuilding from NumPy.
• Use SimpleITK index order (x, y, z, ...); NumPy scalar arrays expose spatial axes in reverse order such as (z, y, x) for 3D.
• sitk.GetArrayFromImage(image) returns a mutable deep copy; sitk.GetArrayViewFromImage(image) returns a read-only view tied to the image buffer.
• sitk.GetImageFromArray(array, isVector=None) creates a new image with default geometry, reverses spatial axes, and treats the final axis as components only when vector conversion applies.