Merge remote-tracking branch 'upstream/3.4' into merge-3.4

diff --cc modules/calib3d/misc/java/test/Calib3dTest.java
Simple merge

diff --cc modules/calib3d/src/fisheye.cpp
index c150d10,a562bd2..6282426
--- 1/modules/calib3d/src/fisheye.cpp
--- 2/modules/calib3d/src/fisheye.cpp
+++ b/modules/calib3d/src/fisheye.cpp
@@@ -396,16 -386,13 +396,16 @@@ void cv::fisheye::undistortPoints( Inpu
          // clip values so we still get plausible results for super fisheye images > 180 grad
          theta_d = min(max(-CV_PI/2., theta_d), CV_PI/2.);
  
 -        if (theta_d > 1e-8)
 +        bool converged = false;
 +        double theta = theta_d;
 +
 +        double scale = 0.0;
 +
 +        if (!isEps || fabs(theta_d) > criteria.epsilon)
          {
-             // compensate distortion iteratively
+             // compensate distortion iteratively using Newton method
 -            double theta = theta_d;
  
 -            const double EPS = 1e-8; // or std::numeric_limits<double>::epsilon();
 -            for (int j = 0; j < 10; j++)
 +            for (int j = 0; j < maxCount; j++)
              {
                  double theta2 = theta*theta, theta4 = theta2*theta2, theta6 = theta4*theta2, theta8 = theta6*theta2;
                  double k0_theta2 = k[0] * theta2, k1_theta4 = k[1] * theta4, k2_theta6 = k[2] * theta6, k3_theta8 = k[3] * theta8;

diff --cc modules/calib3d/test/test_fisheye.cpp
index eecbcd3,2e12cd8..da95156
--- 1/modules/calib3d/test/test_fisheye.cpp
--- 2/modules/calib3d/test/test_fisheye.cpp
+++ b/modules/calib3d/test/test_fisheye.cpp
@@@ -152,6 -112,6 +152,15 @@@ TEST_F(fisheyeTest, distortUndistortPoi
  
  TEST_F(fisheyeTest, undistortImage)
  {
++    // we use it to reduce patch size for images in testdata
++    auto throwAwayHalf = [](Mat img)
++    {
++        int whalf = img.cols / 2, hhalf = img.rows / 2;
++        Rect tl(0, 0, whalf, hhalf), br(whalf, hhalf, whalf, hhalf);
++        img(tl) = 0;
++        img(br) = 0;
++    };
++
      cv::Matx33d theK = this->K;
      cv::Mat theD = cv::Mat(this->D);
      std::string file = combine(datasets_repository_path, "/calib-3_stereo_from_JY/left/stereo_pair_014.jpg");
@@@ -190,107 -159,6 +208,109 @@@
      }
  }
  
-     CV_Assert(cv::imwrite(combine(datasets_repository_path, "new_distortion.png"), image_projected));
 +TEST_F(fisheyeTest, undistortAndDistortImage)
 +{
 +    cv::Matx33d K_src = this->K;
 +    cv::Mat D_src = cv::Mat(this->D);
 +    std::string file = combine(datasets_repository_path, "/calib-3_stereo_from_JY/left/stereo_pair_014.jpg");
 +    cv::Matx33d K_dst = K_src;
 +    cv::Mat image = cv::imread(file), image_projected;
 +    cv::Vec4d D_dst_vec (-1.0, 0.0, 0.0, 0.0);
 +    cv::Mat D_dst = cv::Mat(D_dst_vec);
 +
 +    int imageWidth = (int)this->imageSize.width;
 +    int imageHeight = (int)this->imageSize.height;
 +
 +    cv::Mat imagePoints(imageHeight, imageWidth, CV_32FC2), undPoints, distPoints;
 +    cv::Vec2f* pts = imagePoints.ptr<cv::Vec2f>();
 +
 +    for(int y = 0, k = 0; y < imageHeight; ++y)
 +    {
 +        for(int x = 0; x < imageWidth; ++x)
 +        {
 +            cv::Vec2f point((float)x, (float)y);
 +            pts[k++] = point;
 +        }
 +    }
 +
 +    cv::fisheye::undistortPoints(imagePoints, undPoints, K_dst, D_dst);
 +    cv::fisheye::distortPoints(undPoints, distPoints, K_src, D_src);
 +    cv::remap(image, image_projected, distPoints, cv::noArray(), cv::INTER_LINEAR);
 +
 +    float dx, dy, r_sq;
 +    float R_MAX = 250;
 +    float imageCenterX = (float)imageWidth / 2;
 +    float imageCenterY = (float)imageHeight / 2;
 +
 +    cv::Mat undPointsGt(imageHeight, imageWidth, CV_32FC2);
 +    cv::Mat imageGt(imageHeight, imageWidth, CV_8UC3);
 +
 +    for(int y = 0; y < imageHeight; ++y)
 +    {
 +        for(int x = 0; x < imageWidth; ++x)
 +        {
 +            dx = x - imageCenterX;
 +            dy = y - imageCenterY;
 +            r_sq = dy * dy + dx * dx;
 +
 +            Vec2f & und_vec = undPoints.at<Vec2f>(y,x);
 +            Vec3b & pixel = image_projected.at<Vec3b>(y,x);
 +
 +            Vec2f & undist_vec_gt = undPointsGt.at<Vec2f>(y,x);
 +            Vec3b & pixel_gt = imageGt.at<Vec3b>(y,x);
 +
 +            if (r_sq > R_MAX * R_MAX)
 +            {
 +
 +                undist_vec_gt[0] = -1e6;
 +                undist_vec_gt[1] = -1e6;
 +
 +                pixel_gt[0] = 0;
 +                pixel_gt[1] = 0;
 +                pixel_gt[2] = 0;
 +            }
 +            else
 +            {
 +                undist_vec_gt[0] = und_vec[0];
 +                undist_vec_gt[1] = und_vec[1];
 +
 +                pixel_gt[0] = pixel[0];
 +                pixel_gt[1] = pixel[1];
 +                pixel_gt[2] = pixel[2];
 +            }
 +
 +        }
 +    }
 +
 +    EXPECT_MAT_NEAR(undPoints, undPointsGt, 1e-10);
 +    EXPECT_MAT_NEAR(image_projected, imageGt, 1e-10);
 +
 +    Vec2f dist_point_1 = distPoints.at<Vec2f>(400, 640);
 +    Vec2f dist_point_1_gt(640.044f, 400.041f);
 +
 +    Vec2f dist_point_2 = distPoints.at<Vec2f>(400, 440);
 +    Vec2f dist_point_2_gt(409.731f, 403.029f);
 +
 +    Vec2f dist_point_3 = distPoints.at<Vec2f>(200, 640);
 +    Vec2f dist_point_3_gt(643.341f, 168.896f);
 +
 +    Vec2f dist_point_4 = distPoints.at<Vec2f>(300, 480);
 +    Vec2f dist_point_4_gt(463.402f, 290.317f);
 +
 +    Vec2f dist_point_5 = distPoints.at<Vec2f>(550, 750);
 +    Vec2f dist_point_5_gt(797.51f, 611.637f);
 +
 +    EXPECT_MAT_NEAR(dist_point_1, dist_point_1_gt, 1e-2);
 +    EXPECT_MAT_NEAR(dist_point_2, dist_point_2_gt, 1e-2);
 +    EXPECT_MAT_NEAR(dist_point_3, dist_point_3_gt, 1e-2);
 +    EXPECT_MAT_NEAR(dist_point_4, dist_point_4_gt, 1e-2);
 +    EXPECT_MAT_NEAR(dist_point_5, dist_point_5_gt, 1e-2);
 +
++    // Add the "--test_debug" to arguments for file output
++    if (cvtest::debugLevel > 0)
++        cv::imwrite(combine(datasets_repository_path, "new_distortion.png"), image_projected);
 +}
 +
  TEST_F(fisheyeTest, jacobians)
  {
      int n = 10;