Method medianCutQuantization

pixelizer.js:748–803

(imageData, colorCount)

    // 复用existing的medianCutQuantization方法
    medianCutQuantization(imageData, colorCount) {
        // 从main.js复制并修改的方法
        const pixels = [];
        for (let i = 0; i < imageData.data.length; i += 4) {
            pixels.push([
                imageData.data[i],
                imageData.data[i + 1],
                imageData.data[i + 2],
                imageData.data[i + 3]
            ]);
        }

        let boxes = [new ColorBox(pixels)];
        
        while (boxes.length < colorCount) {
            let boxToSplit = boxes.reduce((a, b) => 
                a.largestRange > b.largestRange ? a : b
            );
            
            boxes = boxes.filter(box => box !== boxToSplit);
            
            const newBoxes = boxToSplit.split();
            if (newBoxes) {
                boxes.push(...newBoxes);
            } else {
                break;
            }
        }

        const palette = boxes.map(box => box.getAverageColor());

        for (let i = 0; i < imageData.data.length; i += 4) {
            const pixel = [
                imageData.data[i],
                imageData.data[i + 1],
                imageData.data[i + 2],
                imageData.data[i + 3]
            ];
            
            let minDistance = Infinity;
            let closestColor = null;
            
            for (const color of palette) {
                const distance = this.colorDistance(pixel, color);
                if (distance < minDistance) {
                    minDistance = distance;
                    closestColor = color;
                }
            }
            
            imageData.data[i] = closestColor[0];
            imageData.data[i + 1] = closestColor[1];
            imageData.data[i + 2] = closestColor[2];
            imageData.data[i + 3] = closestColor[3];
        }
    }

    colorDistance(color1, color2) {