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I have a matrix where each element is a class ID. I need to transform this matrix into a one-hot encoded matrix with n channels where n is the number of classes. I want to do this for any two data types (input and output) with a single compact function. How can I best make use of templates, CV_MAKETYPE, etc?

My current function:

void one_hot_encode(cv::InputArray src, cv::OutputArray dst, int n_classes) {   
  dst.create(src.size(), CV_32FC(n_classes));                                     
  cv::Mat& dst_mat = dst.getMatRef();                                           
  dst_mat.setTo(0);                                                             

  const cv::Mat src_mat = src.getMat();
  for (int i = 0; i < src_mat.rows; ++i) {
    auto* src_ptr = src_mat.ptr<uint8_t>(i);
    auto* dst_ptr = dst_mat.ptr<float>(i);

    for (int j = 0; j < src_mat.cols; ++j) {
      dst_ptr[j*n_classes + src_ptr[j]] = 1;
    }
  }
}