Added blueShift to MagickImage.

Author: dlemstra

src/magick-image.ts

@@ -589,6 +589,17 @@ export interface IMagickImage extends IDisposable {
      */
     blackThreshold(threshold: Percentage, channels: Channels): void;
 
+    /**
+     * Simulate a scene at nighttime in the moonlight.
+     */
+    blueShift(): void;
+
+    /**
+     * Simulate a scene at nighttime in the moonlight.
+     * @param factor The factor to use.
+     */
+    blueShift(factor: number): void;
+
     /**
      * Blur image with the default blur factor (0x1).
      */
@@ -2574,6 +2585,16 @@ export class MagickImage extends NativeInstance implements IMagickImage {
         });
     }
 
+    blueShift(): void
+    blueShift(factor: number): void
+    blueShift(factorOrUndefined?: number): void {
+        const factor = this.valueOrDefault(factorOrUndefined, 1.5);
+        this.useException(exception => {
+            const instance = ImageMagick._api._MagickImage_BlueShift(this._instance, factor, exception.ptr);
+            this._setInstance(instance, exception);
+        });
+    }
+
     blur(): void;
     blur(channels: Channels): void;
     blur(radius: number, sigma: number): void;

tests/magick-image/blue-shift.spec.ts

@@ -0,0 +1,30 @@
+/*
+  Copyright Dirk Lemstra https://github.com/dlemstra/magick-wasm.
+  Licensed under the Apache License, Version 2.0.
+*/
+
+import { ErrorMetric } from '@src/enums/error-metric';
+import { TestFiles } from '@test/test-files';
+
+describe('MagickImage#blueShift', () => {
+    it('should change pixels of the image', () => {
+        TestFiles.Images.Builtin.logo.use(image => {
+            image.blueShift(1.5);
+
+            expect(image).toHavePixelWithColor(235, 65, '#ffbfbf');
+            expect(image).toHavePixelWithColor(340, 260, '#838a9f');
+        });
+    });
+
+    it('should use the correct default factor value', () => {
+        TestFiles.Images.Builtin.logo.use(image => {
+            image.clone(other => {
+                image.blueShift();
+                other.blueShift(1.5);
+
+                const difference = other.compare(image, ErrorMetric.RootMeanSquared);
+                expect(difference).toBe(0);
+            })
+        });
+    });
+});