Pixel access in OpenCV 2.2

In opencv 2.2, I’d use the C++ interface.

cv::Mat in = /* your image goes here, 
                assuming single-channel image with 8bits per pixel */
for(int row = 0; row < in.rows; ++row) {
    unsigned char* inp  = in.ptr<unsigned char>(row);
    for (int col = 0; col < in.cols; ++col) {
        if (*inp++ == 0) {
            std::cout << '1';
        } else {
            std::cout << '0';
        }
        std::cout << std::endl;
    }
}