如何使用Flutter对图像进行像素化？

dependencies:
  flutter:
    sdk: flutter
  image: ^3.0.2

ImageProvider imageProvider = NetworkImage('https://example.com/image.jpg');

import 'package:image/image.dart' as img;

img.Image image = img.decodeImage(await imageProvider.readAsBytes());

int blockSize = 10; // 像素块大小
for (int y = 0; y < image.height; y += blockSize) {
  for (int x = 0; x < image.width; x += blockSize) {
    int pixelR = 0, pixelG = 0, pixelB = 0;
    int count = 0;

    // 计算像素块内的颜色平均值
    for (int blockY = y; blockY < y + blockSize && blockY < image.height; blockY++) {
      for (int blockX = x; blockX < x + blockSize && blockX < image.width; blockX++) {
        int pixel = image.getPixel(blockX, blockY);
        pixelR += img.getRed(pixel);
        pixelG += img.getGreen(pixel);
        pixelB += img.getBlue(pixel);
        count++;
      }
    }

    // 设置像素块内所有像素的颜色为平均值
    int avgR = pixelR ~/ count;
    int avgG = pixelG ~/ count;
    int avgB = pixelB ~/ count;
    for (int blockY = y; blockY < y + blockSize && blockY < image.height; blockY++) {
      for (int blockX = x; blockX < x + blockSize && blockX < image.width; blockX++) {
        image.setPixel(blockX, blockY, img.getColor(avgR, avgG, avgB));
      }
    }
  }
}

Image processedImage = Image.memory(img.encodePng(image));