Merge pull request #18646 from qchateau:wave-auto

* stitching: add WAVE_CORRECT_AUTO

* stitching: use CV_EXPORTS

modules/stitching/test/test_wave_correction.cpp

@@ -0,0 +1,50 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+
+#include "test_precomp.hpp"
+
+namespace opencv_test {
+namespace {
+
+detail::WaveCorrectKind correctionKind(const std::vector<UMat>& images)
+{
+
+    Ptr<Stitcher> stitcher = Stitcher::create(Stitcher::PANORAMA);
+    stitcher->estimateTransform(images);
+
+    std::vector<Mat> rmats;
+    auto cameras = stitcher->cameras();
+    for (const auto& camera: cameras)
+        rmats.push_back(camera.R);
+
+    return detail::autoDetectWaveCorrectKind(rmats);
+}
+
+TEST(WaveCorrection, AutoWaveCorrection)
+{
+    std::vector<UMat> images(2);
+    imread(cvtest::TS::ptr()->get_data_path() + "stitching/s1.jpg").copyTo(images[0]);
+    imread(cvtest::TS::ptr()->get_data_path() + "stitching/s2.jpg").copyTo(images[1]);
+
+    EXPECT_EQ(detail::WAVE_CORRECT_HORIZ, correctionKind(images));
+
+    std::vector<UMat> rotated_images(2);
+    rotate(images[0], rotated_images[0], cv::ROTATE_90_CLOCKWISE);
+    rotate(images[1], rotated_images[1], cv::ROTATE_90_CLOCKWISE);
+
+    EXPECT_EQ(detail::WAVE_CORRECT_VERT, correctionKind(rotated_images));
+
+    rotate(images[0], rotated_images[0], cv::ROTATE_90_COUNTERCLOCKWISE);
+    rotate(images[1], rotated_images[1], cv::ROTATE_90_COUNTERCLOCKWISE);
+
+    EXPECT_EQ(detail::WAVE_CORRECT_VERT, correctionKind(rotated_images));
+
+    rotate(images[0], rotated_images[0], cv::ROTATE_180);
+    rotate(images[1], rotated_images[1], cv::ROTATE_180);
+
+    EXPECT_EQ(detail::WAVE_CORRECT_HORIZ, correctionKind(rotated_images));
+}
+
+} // namespace
+} // namespace opencv_test