import {logger} from '../utils/logger';
/**
* Minimum window width value.
*
* Ref: {@link http://dicom.nema.org/medical/dicom/2022a/output/chtml/part03/sect_C.11.2.html#sect_C.11.2.1.2}.
*/
const minWindowWidth = 1;
/**
* Validate an input window width.
*
* @param {number} value The value to test.
* @returns {number} A valid window width.
*/
export function validateWindowWidth(value) {
return value < minWindowWidth ? minWindowWidth : value;
}
/**
* Window and Level also known as window width and center.
*/
export class WindowLevel {
/**
* The window center.
*
* @type {number}
*/
center;
/**
* The window width.
*
* @type {number}
*/
width;
/**
* @param {number} center The window center.
* @param {number} width The window width.
*/
constructor(center, width) {
// check width
if (width < minWindowWidth) {
logger.warn('Using minimum window width since input is not valid: ' +
width);
width = minWindowWidth;
}
this.center = center;
this.width = width;
}
/**
* Check for equality.
*
* @param {WindowLevel} rhs The other object to compare to.
* @returns {boolean} True if both objects are equal.
*/
equals(rhs) {
return rhs !== null &&
typeof rhs !== 'undefined' &&
this.center === rhs.center &&
this.width === rhs.width;
}
} // WindowLevel class
/**
* List of default window level presets.
*
* @type {Object.<string, Object.<string, WindowLevel>>}
*/
export const defaultPresets = {
CT: {
mediastinum: new WindowLevel(40, 400),
lung: new WindowLevel(-500, 1500),
bone: new WindowLevel(500, 2000),
brain: new WindowLevel(40, 80),
head: new WindowLevel(90, 350)
}
};