EISATS

EISATS | Reinhard Klette: CCVというコンピュータビジョン向けのデータセットがありまして

EISATS
The .enpeda.. Image Sequence Analysis Test Site (EISATS) offers sets of image sequences for the purpose of comparative performance evaluation of stereo vision, optic flow, motion analysis, or further techniques in computer vision.

そのうちSET2は車載シーンが合成画像で作成されており
オプティカルフロー、視差、エゴモーション等の正解データが取得できます

ときどきOpenCV上で利用するのですが、毎度データの読み込み方法を忘れるので
自分へのメモとして各データを読み込んで表示するサンプルプログラムを作成しました
github.com

使用する際は前述のSET2から
SEQUENCE2のデータを適当なディレクトリにダウンロード・解凍して

/home/hoge/EISATS/SET2/S2/
├── colour-left-S2
├── disparityGT-S2
├── egoMotion
├── flowX-S2
├── flowY-S2

そのディレクトリをプログラムに渡します

./eisats-synthesized-sequences /home/hoge/EISATS/SET2/S2/

ソースファイルは1個だけなので全部載せておきます

#include <iostream>
#include <iomanip>
#include <string>
#include <sstream>
#include <fstream>
#include <opencv2/opencv.hpp>

namespace {

	std::string numberString(int n)
	{
		std::stringstream ss;
		ss << std::setw(3) << std::setfill('0') << n;
		return ss.str();
	}

	cv::Mat readRaw(const std::string& filename)
	{
		std::ifstream ifs(filename, std::ios::binary);
		if (ifs.fail())
			return cv::Mat();

		std::string line;
		while (getline(ifs, line) && line[0] == '#') {}

		int width, height, depth;
		sscanf(line.c_str(), "%d %d %d", &width, &height, &depth);
		CV_Assert(depth == 32);

		cv::Mat img(height, width, CV_32F);
		ifs.read((char *)img.data, sizeof(float) * width * height);

		return img;
	}

	void readEgoMotion(const std::string& filename, cv::Matx33d& R, cv::Matx31d& t)
	{
		std::ifstream ifs(filename);
		if (ifs.fail())
			return;

		std::string line;
		while (getline(ifs, line) && line[0] == '#') {}

		sscanf(line.c_str(), "%lf %lf %lf %lf", &R(0, 0), &R(0, 1), &R(0, 2), &t(0)); getline(ifs, line);
		sscanf(line.c_str(), "%lf %lf %lf %lf", &R(1, 0), &R(1, 1), &R(1, 2), &t(1)); getline(ifs, line);
		sscanf(line.c_str(), "%lf %lf %lf %lf", &R(2, 0), &R(2, 1), &R(2, 2), &t(2));
	}

	void drawOpticalFlow(cv::Mat& img, const cv::Mat1f& flowx, const cv::Mat1f& flowy)
	{
		float maxnorm = 0;
		for (int i = 0; i < flowx.rows; ++i)
		{
			for (int j = 0; j < flowx.cols; ++j)
			{
				float x = flowx(i, j);
				float y = flowy(i, j);
				maxnorm = std::max(maxnorm, sqrtf(x * x + y * y));
			}
		}

		img.create(flowx.size(), CV_8UC3);
		for (int i = 0; i < flowx.rows; ++i)
		{
			for (int j = 0; j < flowx.cols; ++j)
			{
				float x = flowx(i, j);
				float y = flowy(i, j);

				// Convert flow angle to hue
				float angle = atan2f(y, x);
				if (angle < 0.f) angle += (float)(2 * CV_PI);
				angle /= (float)(2 * CV_PI);
				uchar hue = static_cast<uchar>(180 * angle);

				// Convert flow norm to saturation
				float norm = sqrtf(x * x + y * y) / maxnorm;
				uchar sat = static_cast<uchar>(255 * norm);

				img.at<cv::Vec3b>(i, j) = cv::Vec3b(hue, sat, 255);
			}
		}

		cv::cvtColor(img, img, cv::COLOR_HSV2BGR);
	}

} /* namespace */

int main(int argc, char *argv[])
{
	if (argc < 2)
	{
		std::cerr << "Usage: " << argv[0] << " [data path]" << std::endl;
		return -1;
	}

	std::string dataPath(argv[1]);

	for (int frameNo = 2; ; ++frameNo)
	{
		// Read left image
		cv::Mat leftImg = cv::imread(dataPath + "/colour-left-S2/img_c0_" + numberString(frameNo) + ".ppm");
		if (leftImg.empty())
			break;

		// Read optical flow map
		cv::Mat flowx = readRaw(dataPath + "/flowX-S2/flowU_from_" + numberString(frameNo - 1) + "_to_" + numberString(frameNo) + ".raw");
		cv::Mat flowy = readRaw(dataPath + "/flowY-S2/flowV_from_" + numberString(frameNo - 1) + "_to_" + numberString(frameNo) + ".raw");
		if (flowx.empty() || flowy.empty())
			break;

		// Read disparity map
		cv::Mat disp = readRaw(dataPath + "/disparityGT-S2/stereo_" + numberString(frameNo) + ".raw");
		if (disp.empty())
			break;

		// Read ego-motion
		cv::Matx33d R;
		cv::Matx31d t, r;
		readEgoMotion(dataPath + "/egoMotion/from_" + numberString(frameNo - 1) + "_to_" + numberString(frameNo) + ".txt", R, t);
		cv::Rodrigues(R, r);

		// Draw and display image
		cv::Mat flowImg, dispImg;
		drawOpticalFlow(flowImg, flowx, flowy);
		cv::normalize(disp, dispImg, 0.0, 1.0, cv::NORM_MINMAX);

		cv::putText(leftImg, "Rotation: " + std::to_string(r(0)) + " " + std::to_string(r(1)) + " " + std::to_string(r(2)),
			cv::Point(10, 20), 0, 0.5, cv::Scalar(0, 255, 255));
		cv::putText(leftImg, "Translation: " + std::to_string(t(0)) + " " + std::to_string(t(1)) + " " + std::to_string(t(2)),
			cv::Point(10, 40), 0, 0.5, cv::Scalar(0, 255, 255));

		cv::imshow("Left image", 16 * leftImg);
		cv::imshow("Flow image", flowImg);
		cv::imshow("Disp image", dispImg);

		char c = cv::waitKey(100);
		if (c == 27) // ESC
			break;
	}

	return 0;
}