Thinh Lam
33 lines
1.3 KiB
TypeScript
33 lines
1.3 KiB
TypeScript
/**
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* Multi-label segmentation helpers (pure — no VTK, no DOM, unit-testable).
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*
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* A single labelsTr/<case>.nii.gz can encode many organs as integer voxel values
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* (e.g. TotalSegmentator: 1..117). These split such a volume's scalar array into the
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* distinct label values present, and into a per-value binary (0/1) mask the renderer
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* can extract as one coloured iso-surface. The VTK wrappers live in `niftiLoader`.
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*/
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/** Distinct non-zero integer label values present in a segmentation's scalar array, ascending. */
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export function distinctLabelValues(scalars: ArrayLike<number>): number[] {
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const seen = new Set<number>();
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for (let i = 0; i < scalars.length; i++) {
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const v = scalars[i];
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if (v > 0 && Number.isInteger(v)) seen.add(v);
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}
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return [...seen].sort((a, b) => a - b);
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}
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/** A binary (0/1) Uint8Array mask: 1 where the scalar equals `value`, else 0. */
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export function binaryLabelMask(scalars: ArrayLike<number>, value: number): Uint8Array {
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const out = new Uint8Array(scalars.length);
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for (let i = 0; i < scalars.length; i++) {
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if (scalars[i] === value) out[i] = 1;
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}
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return out;
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}
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/** True when a segmentation holds more than one distinct organ label (so it is worth splitting). */
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export function isMultiLabel(scalars: ArrayLike<number>): boolean {
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return distinctLabelValues(scalars).length > 1;
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}
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