cyberchef/src/core/operations/SharpenImage.mjs

/**
 * @author j433866 [j433866@gmail.com]
 * @copyright Crown Copyright 2019
 * @license Apache-2.0
 */

import Operation from "../Operation.mjs";
import OperationError from "../errors/OperationError.mjs";
import { isImage } from "../lib/FileType.mjs";
import { toBase64 } from "../lib/Base64.mjs";
import { isWorkerEnvironment } from "../Utils.mjs";
import { Jimp, JimpMime } from "jimp";

/**
 * Sharpen Image operation
 */
class SharpenImage extends Operation {
    /**
     * SharpenImage constructor
     */
    constructor() {
        super();

        this.name = "Sharpen Image";
        this.module = "Image";
        this.description = "Sharpens an image (Unsharp mask)";
        this.infoURL = "https://wikipedia.org/wiki/Unsharp_masking";
        this.inputType = "ArrayBuffer";
        this.outputType = "ArrayBuffer";
        this.presentType = "html";
        this.args = [
            {
                name: "Radius",
                type: "number",
                value: 2,
                min: 1,
            },
            {
                name: "Amount",
                type: "number",
                value: 1,
                min: 0,
                step: 0.1,
            },
            {
                name: "Threshold",
                type: "number",
                value: 10,
                min: 0,
                max: 100,
            },
        ];
    }

    /**
     * @param {ArrayBuffer} input
     * @param {Object[]} args
     * @returns {byteArray}
     */
    async run(input, args) {
        const [radius, amount, threshold] = args;

        if (!isImage(input)) {
            throw new OperationError("Invalid file type.");
        }

        let image;
        try {
            image = await Jimp.read(input);
        } catch (err) {
            throw new OperationError(`Error loading image. (${err})`);
        }

        try {
            if (isWorkerEnvironment())
                self.sendStatusMessage("Sharpening image... (Cloning image)");
            const blurMask = image.clone();

            if (isWorkerEnvironment())
                self.sendStatusMessage(
                    "Sharpening image... (Blurring cloned image)",
                );
            const blurImage = image.clone().gaussian(radius);

            if (isWorkerEnvironment())
                self.sendStatusMessage(
                    "Sharpening image... (Creating unsharp mask)",
                );
            blurMask.scan(
                0,
                0,
                blurMask.bitmap.width,
                blurMask.bitmap.height,
                function (x, y, idx) {
                    const blurRed = blurImage.bitmap.data[idx];
                    const blurGreen = blurImage.bitmap.data[idx + 1];
                    const blurBlue = blurImage.bitmap.data[idx + 2];

                    const normalRed = this.bitmap.data[idx];
                    const normalGreen = this.bitmap.data[idx + 1];
                    const normalBlue = this.bitmap.data[idx + 2];

                    // Subtract blurred pixel value from normal image
                    this.bitmap.data[idx] =
                        normalRed > blurRed ? normalRed - blurRed : 0;
                    this.bitmap.data[idx + 1] =
                        normalGreen > blurGreen ? normalGreen - blurGreen : 0;
                    this.bitmap.data[idx + 2] =
                        normalBlue > blurBlue ? normalBlue - blurBlue : 0;
                },
            );

            if (isWorkerEnvironment())
                self.sendStatusMessage(
                    "Sharpening image... (Merging with unsharp mask)",
                );
            image.scan(
                0,
                0,
                image.bitmap.width,
                image.bitmap.height,
                function (x, y, idx) {
                    let maskRed = blurMask.bitmap.data[idx];
                    let maskGreen = blurMask.bitmap.data[idx + 1];
                    let maskBlue = blurMask.bitmap.data[idx + 2];

                    const normalRed = this.bitmap.data[idx];
                    const normalGreen = this.bitmap.data[idx + 1];
                    const normalBlue = this.bitmap.data[idx + 2];

                    // Calculate luminance
                    const maskLuminance =
                        0.2126 * maskRed +
                        0.7152 * maskGreen +
                        0.0722 * maskBlue;
                    const normalLuminance =
                        0.2126 * normalRed +
                        0.7152 * normalGreen +
                        0.0722 * normalBlue;

                    let luminanceDiff;
                    if (maskLuminance > normalLuminance) {
                        luminanceDiff = maskLuminance - normalLuminance;
                    } else {
                        luminanceDiff = normalLuminance - maskLuminance;
                    }

                    // Scale mask colours by amount
                    maskRed = maskRed * amount;
                    maskGreen = maskGreen * amount;
                    maskBlue = maskBlue * amount;

                    // Only change pixel value if the difference is higher than threshold
                    if ((luminanceDiff / 255) * 100 >= threshold) {
                        this.bitmap.data[idx] =
                            normalRed + maskRed <= 255 ?
                                normalRed + maskRed :
                                255;
                        this.bitmap.data[idx + 1] =
                            normalGreen + maskGreen <= 255 ?
                                normalGreen + maskGreen :
                                255;
                        this.bitmap.data[idx + 2] =
                            normalBlue + maskBlue <= 255 ?
                                normalBlue + maskBlue :
                                255;
                    }
                },
            );

            let imageBuffer;
            if (image.mime === "image/gif") {
                imageBuffer = await image.getBuffer(JimpMime.png);
            } else {
                imageBuffer = await image.getBuffer(image.mime);
            }
            return imageBuffer.buffer;
        } catch (err) {
            throw new OperationError(`Error sharpening image. (${err})`);
        }
    }

    /**
     * Displays the sharpened image using HTML for web apps
     * @param {ArrayBuffer} data
     * @returns {html}
     */
    present(data) {
        if (!data.byteLength) return "";
        const dataArray = new Uint8Array(data);

        const type = isImage(dataArray);
        if (!type) {
            throw new OperationError("Invalid file type.");
        }

        return `<img src="data:${type};base64,${toBase64(dataArray)}">`;
    }
}

export default SharpenImage;