lbp.cpp

#include <opencv2/opencv.hpp>
#include <ctime>

std::string input_image_name = "test.jpg";

int lbp_weights[8] = {128, 64, 32, 16, 8, 4, 2, 1};

int main(int argc, char* argv[]) {

	// 入力画像の取得
	cv::Mat input_image;
	input_image = cv::imread(input_image_name, 0);
	if (input_image.empty() == true) {
		std::cerr << input_image_name << "が見つからない" << std::endl;
		return -1;
	}
	std::cout << "Size(input_image) : " << input_image.cols << "×" << input_image.rows << std::endl;
	cv::imshow("Input_image", input_image);
	cv::waitKey(0);

	// 出力用画像の用意	
	cv::Mat1b lbp_image(input_image.rows, input_image.cols);

	// 入力画像の上下左右に1pixel分のPaddingを追加する
	cv::Mat input_pad_image;
	copyMakeBorder(input_image, input_pad_image, 1, 1, 1, 1, cv::BORDER_REPLICATE);
	std::cout << "Size(input_pad_image) : " << input_pad_image.cols << "×" << input_pad_image.rows << std::endl;

	// 計算時間測定用
	int start = clock();

	// LBP特徴量の計算
	for (int y = 1; y < input_pad_image.rows - 1; y++) {
		for (int x = 1; x < input_pad_image.cols - 1; x++) {

			// 周辺画素入力用配列
			int pixel_value[8] = { 0 };
			int thresholded_value[8] = { 0 };

			// 注目画素
			int center_value = input_pad_image.at<unsigned char>(y, x);

			// 周辺画素の値を取得
			pixel_value[0] = input_pad_image.at<unsigned char>(y - 1, x - 1);
			pixel_value[1] = input_pad_image.at<unsigned char>(y - 1, x);
			pixel_value[2] = input_pad_image.at<unsigned char>(y - 1, x + 1);
			pixel_value[3] = input_pad_image.at<unsigned char>(y, x + 1);
			pixel_value[4] = input_pad_image.at<unsigned char>(y + 1, x + 1);
			pixel_value[5] = input_pad_image.at<unsigned char>(y + 1, x);
			pixel_value[6] = input_pad_image.at<unsigned char>(y + 1, x - 1);
			pixel_value[7] = input_pad_image.at<unsigned char>(y, x - 1);

			int lbp_result = 0;
			
			// LBP値を計算(0～255)
			for (int i = 0; i < 8; i++) {
				if (pixel_value[i] >= center_value){
					lbp_result += lbp_weights[i];
				}
			}

			// 結果の取得
			lbp_image.at<unsigned char>(y - 1, x - 1) = lbp_result;
		}
	}

	// 計算時間測定用
	int end = clock();

	std::cout << "Processing time : " << end - start << "[ms]" << std::endl;

	// 結果の保存と表示
	imwrite("output.png", lbp_image);
	cv::imshow("LBP_result_image", lbp_image);
	cv::waitKey(0);

	return 0;
}