如何将HOG特征添加到矩阵（matlab）

在提取图像文件夹的HOG特征后，我想将所有这些结果添加到一个矩阵中。我怎么能做到？这是我在matlab中的代码：

training_female = 'E:\Training Set\Female Images';

% read all images with specified extention, its jpg in our case
filenames = dir(fullfile(training_female, '*.jpg'));

% count total number of photos present in that folder
total_images = numel(filenames);

for n = 1:total_images

% Specify images names with full path and extension    
full_name= fullfile(training_female, filenames(n).name);

% Read images
training_images = imread(full_name);
[featureVector, hogVisualization] = extractHOGFeatures(training_images);
figure (n)

    % Show all images
    imshow(training_images); hold on;                  
    plot(hogVisualization);
end

通过查看，调用

extractHOGFeatures

计算给定输入图像的

1 x N

向量。因为计算这个的输出大小可能有点麻烦，这也取决于为HOG检测器设置的参数，所以最好先创建一个空矩阵，并在每次迭代时动态连接特征。通常，为了提高性能，如果希望在迭代的基础上填充元素，您需要预先分配一个矩阵。不这样做会使性能略有下降，但考虑到您的情况，这是最适合的。您可能需要调整HOG参数，如果我们采用动态方式进行调整，那么就不必再为确定矩阵的总大小而头疼了

那就这样做吧。我已将

%//新的

标记放置在修改代码的位置：

training_female = 'E:\Training Set\Female Images';

% read all images with specified extention, its jpg in our case
filenames = dir(fullfile(training_female, '*.jpg'));

% count total number of photos present in that folder
total_images = numel(filenames);

featureMatrix = []; %// New - Declare feature matrix

for n = 1:total_images

    % Specify images names with full path and extension    
    full_name= fullfile(training_female, filenames(n).name);

    % Read images
    training_images = imread(full_name);
    [featureVector, hogVisualization] = extractHOGFeatures(training_images);

    %// New - Add feature vector to matrix
    featureMatrix = [featureMatrix; featureVector];
    figure(n);

    % Show all images
    imshow(training_images); hold on;                  
    plot(hogVisualization);
end

featureMatrix

将包含您的HOG特征，其中每行对应于每个图像。因此，对于特定图像

i

，您可以通过以下方式确定HOG特征：

feature = featureMatrix(i,:);

警告 我需要指出的是，上面的代码假设目录中的所有图像大小相同。如果不是，那么每个HOG调用的输出向量大小将不同。如果是这种情况，您将需要一个单元阵列来适应不同的大小

因此，请这样做：

training_female = 'E:\Training Set\Female Images';

% read all images with specified extention, its jpg in our case
filenames = dir(fullfile(training_female, '*.jpg'));

% count total number of photos present in that folder
total_images = numel(filenames);

featureMatrix = cell(1,total_images); %// New - Declare feature matrix

for n = 1:total_images

    % Specify images names with full path and extension    
    full_name= fullfile(training_female, filenames(n).name);

    % Read images
    training_images = imread(full_name);
    [featureVector, hogVisualization] = extractHOGFeatures(training_images);

    %// New - Add feature vector to matrix
    featureMatrix{n} = featureVector;
    figure(n);

    % Show all images
    imshow(training_images); hold on;                  
    plot(hogVisualization);
end

要访问特定图像的功能或图像

i

，请执行以下操作：

feature = featureMatrix{i};

---

代码在哪里？您尝试将其加载到矩阵中，但没有成功？我刚刚准备了上面的代码，用于读取和提取一组图像的特征。我需要帮助创建矩阵，并在其中添加猪的功能。我想这个页面可以帮助你：我已经接受了。真的再次感谢rayryeng先生。