下列代码哪一步可以拆分成函数形式写出来，将代码扩充的长一些：I = imread('瑕疵图像.png'); I_gray = rgb2gray(I); sigma = 1; kernel_size = 3; I_blurred = imgaussfilt(I_gray, sigma, 'FilterSize', kernel_size); threshold_low = 0.1; threshold_high = 0.9; I_edges = edge(I_blurred,'Canny',[threshold_low,threshold_high]); connectivity = 8; CC = bwconncomp(I_edges, connectivity); numPixels = cellfun(@numel, CC.PixelIdxList); [~, idx] = max(numPixels); I_target = false(size(I_edges)); I_target(CC.PixelIdxList{idx}) = true; figure; subplot(1,2,1); imshow(I); title('原始图像'); subplot(1,2,2); imshow(I_target); title('提取结果');

可以将以下代码拆分成函数形式：

I_gray = rgb2gray(I);
I_blurred = imgaussfilt(I_gray, sigma, 'FilterSize', kernel_size);
I_edges = edge(I_blurred,'Canny',[threshold_low,threshold_high]);
CC = bwconncomp(I_edges, connectivity);
numPixels = cellfun(@numel, CC.PixelIdxList);
[~, idx] = max(numPixels);
I_target = false(size(I_edges));
I_target(CC.PixelIdxList{idx}) = true;

这些代码实现了图像的灰度化、高斯滤波、Canny边缘检测、连通域分析和目标提取等功能。将其封装成一个函数，可以方便地在其他代码中调用，提高代码的可读性和复用性。函数的形式可以是：

function I_target = extract_defect(I, sigma, kernel_size, threshold_low, threshold_high, connectivity)
    I_gray = rgb2gray(I);
    I_blurred = imgaussfilt(I_gray, sigma, 'FilterSize', kernel_size);
    I_edges = edge(I_blurred,'Canny',[threshold_low,threshold_high]);
    CC = bwconncomp(I_edges, connectivity);
    numPixels = cellfun(@numel, CC.PixelIdxList);
    [~, idx] = max(numPixels);
    I_target = false(size(I_edges));
    I_target(CC.PixelIdxList{idx}) = true;
end

这个函数接受一个RGB图像和一些参数，返回提取出的目标区域。