初次提交

src/utils/utils.ts

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+
+export namespace utils {
+
+	export function rgba2rgb<T extends Uint8Array | Float32Array>(data: T): T {
+		const pixelCount = data.length / 4;
+		const result = new (data.constructor as any)(pixelCount * 3) as T;
+		for (let i = 0; i < pixelCount; i++) {
+			result[i * 3 + 0] = data[i * 4 + 0];
+			result[i * 3 + 1] = data[i * 4 + 1];
+			result[i * 3 + 2] = data[i * 4 + 2];
+		}
+		return result;
+	}
+
+	export function rgb2bgr<T extends Uint8Array | Float32Array>(data: T): T {
+		const pixelCount = data.length / 3;
+		const result = new (data.constructor as any)(pixelCount * 3) as T;
+		for (let i = 0; i < pixelCount; i++) {
+			result[i * 3 + 0] = data[i * 3 + 2];
+			result[i * 3 + 1] = data[i * 3 + 1];
+			result[i * 3 + 2] = data[i * 3 + 0];
+		}
+		return result;
+	}
+
+	export function normalize(data: Uint8Array | Float32Array, mean: number[], std: number[]): Float32Array {
+		const result = new Float32Array(data.length);
+		for (let i = 0; i < data.length; i++) {
+			result[i] = (data[i] - mean[i % mean.length]) / std[i % std.length];
+		}
+		return result;
+	}
+}