opencv/modules/nonfree/test/test_rotation_and_scale_invariance.cpp

711 lines
26 KiB
C++

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#include "test_precomp.hpp"
#include "opencv2/highgui/highgui.hpp"
using namespace std;
using namespace cv;
const string IMAGE_TSUKUBA = "/features2d/tsukuba.png";
const string IMAGE_BIKES = "/detectors_descriptors_evaluation/images_datasets/bikes/img1.png";
#define SHOW_DEBUG_LOG 0
static
Mat generateHomography(float angle)
{
// angle - rotation around Oz in degrees
float angleRadian = static_cast<float>(angle * CV_PI / 180);
Mat H = Mat::eye(3, 3, CV_32FC1);
H.at<float>(0,0) = H.at<float>(1,1) = std::cos(angleRadian);
H.at<float>(0,1) = -std::sin(angleRadian);
H.at<float>(1,0) = std::sin(angleRadian);
return H;
}
static
Mat rotateImage(const Mat& srcImage, float angle, Mat& dstImage, Mat& dstMask)
{
// angle - rotation around Oz in degrees
float diag = std::sqrt(static_cast<float>(srcImage.cols * srcImage.cols + srcImage.rows * srcImage.rows));
Mat LUShift = Mat::eye(3, 3, CV_32FC1); // left up
LUShift.at<float>(0,2) = static_cast<float>(-srcImage.cols/2);
LUShift.at<float>(1,2) = static_cast<float>(-srcImage.rows/2);
Mat RDShift = Mat::eye(3, 3, CV_32FC1); // right down
RDShift.at<float>(0,2) = diag/2;
RDShift.at<float>(1,2) = diag/2;
Size sz(cvRound(diag), cvRound(diag));
Mat srcMask(srcImage.size(), CV_8UC1, Scalar(255));
Mat H = RDShift * generateHomography(angle) * LUShift;
warpPerspective(srcImage, dstImage, H, sz);
warpPerspective(srcMask, dstMask, H, sz);
return H;
}
void rotateKeyPoints(const vector<KeyPoint>& src, const Mat& H, float angle, vector<KeyPoint>& dst)
{
// suppose that H is rotation given from rotateImage() and angle has value passed to rotateImage()
vector<Point2f> srcCenters, dstCenters;
KeyPoint::convert(src, srcCenters);
perspectiveTransform(srcCenters, dstCenters, H);
dst = src;
for(size_t i = 0; i < dst.size(); i++)
{
dst[i].pt = dstCenters[i];
float dstAngle = src[i].angle + angle;
if(dstAngle >= 360.f)
dstAngle -= 360.f;
dst[i].angle = dstAngle;
}
}
void scaleKeyPoints(const vector<KeyPoint>& src, vector<KeyPoint>& dst, float scale)
{
dst.resize(src.size());
for(size_t i = 0; i < src.size(); i++)
dst[i] = KeyPoint(src[i].pt.x * scale, src[i].pt.y * scale, src[i].size * scale, src[i].angle);
}
static
float calcCirclesIntersectArea(const Point2f& p0, float r0, const Point2f& p1, float r1)
{
float c = static_cast<float>(norm(p0 - p1)), sqr_c = c * c;
float sqr_r0 = r0 * r0;
float sqr_r1 = r1 * r1;
if(r0 + r1 <= c)
return 0;
float minR = std::min(r0, r1);
float maxR = std::max(r0, r1);
if(c + minR <= maxR)
return static_cast<float>(CV_PI * minR * minR);
float cos_halfA0 = (sqr_r0 + sqr_c - sqr_r1) / (2 * r0 * c);
float cos_halfA1 = (sqr_r1 + sqr_c - sqr_r0) / (2 * r1 * c);
float A0 = 2 * acos(cos_halfA0);
float A1 = 2 * acos(cos_halfA1);
return 0.5f * sqr_r0 * (A0 - sin(A0)) +
0.5f * sqr_r1 * (A1 - sin(A1));
}
static
float calcIntersectRatio(const Point2f& p0, float r0, const Point2f& p1, float r1)
{
float intersectArea = calcCirclesIntersectArea(p0, r0, p1, r1);
float unionArea = static_cast<float>(CV_PI) * (r0 * r0 + r1 * r1) - intersectArea;
return intersectArea / unionArea;
}
static
void matchKeyPoints(const vector<KeyPoint>& keypoints0, const Mat& H,
const vector<KeyPoint>& keypoints1,
vector<DMatch>& matches)
{
vector<Point2f> points0;
KeyPoint::convert(keypoints0, points0);
Mat points0t;
if(H.empty())
points0t = Mat(points0);
else
perspectiveTransform(Mat(points0), points0t, H);
matches.clear();
vector<uchar> usedMask(keypoints1.size(), 0);
for(int i0 = 0; i0 < static_cast<int>(keypoints0.size()); i0++)
{
int nearestPointIndex = -1;
float maxIntersectRatio = 0.f;
const float r0 = 0.5f * keypoints0[i0].size;
for(size_t i1 = 0; i1 < keypoints1.size(); i1++)
{
if(nearestPointIndex >= 0 && usedMask[i1])
continue;
float r1 = 0.5f * keypoints1[i1].size;
float intersectRatio = calcIntersectRatio(points0t.at<Point2f>(i0), r0,
keypoints1[i1].pt, r1);
if(intersectRatio > maxIntersectRatio)
{
maxIntersectRatio = intersectRatio;
nearestPointIndex = static_cast<int>(i1);
}
}
matches.push_back(DMatch(i0, nearestPointIndex, maxIntersectRatio));
if(nearestPointIndex >= 0)
usedMask[nearestPointIndex] = 1;
}
}
static void removeVerySmallKeypoints(vector<KeyPoint>& keypoints)
{
size_t i, j = 0, n = keypoints.size();
for( i = 0; i < n; i++ )
{
if( (keypoints[i].octave & 128) != 0 )
;
else
keypoints[j++] = keypoints[i];
}
keypoints.resize(j);
}
class DetectorRotationInvarianceTest : public cvtest::BaseTest
{
public:
DetectorRotationInvarianceTest(const Ptr<FeatureDetector>& _featureDetector,
float _minKeyPointMatchesRatio,
float _minAngleInliersRatio) :
featureDetector(_featureDetector),
minKeyPointMatchesRatio(_minKeyPointMatchesRatio),
minAngleInliersRatio(_minAngleInliersRatio)
{
CV_Assert(!featureDetector.empty());
}
protected:
void run(int)
{
const string imageFilename = string(ts->get_data_path()) + IMAGE_TSUKUBA;
// Read test data
Mat image0 = imread(imageFilename), image1, mask1;
if(image0.empty())
{
ts->printf(cvtest::TS::LOG, "Image %s can not be read.\n", imageFilename.c_str());
ts->set_failed_test_info(cvtest::TS::FAIL_INVALID_TEST_DATA);
return;
}
vector<KeyPoint> keypoints0;
featureDetector->detect(image0, keypoints0);
removeVerySmallKeypoints(keypoints0);
if(keypoints0.size() < 15)
CV_Error(CV_StsAssert, "Detector gives too few points in a test image\n");
const int maxAngle = 360, angleStep = 15;
for(int angle = 0; angle < maxAngle; angle += angleStep)
{
Mat H = rotateImage(image0, static_cast<float>(angle), image1, mask1);
vector<KeyPoint> keypoints1;
featureDetector->detect(image1, keypoints1, mask1);
removeVerySmallKeypoints(keypoints1);
vector<DMatch> matches;
matchKeyPoints(keypoints0, H, keypoints1, matches);
int angleInliersCount = 0;
const float minIntersectRatio = 0.5f;
int keyPointMatchesCount = 0;
for(size_t m = 0; m < matches.size(); m++)
{
if(matches[m].distance < minIntersectRatio)
continue;
keyPointMatchesCount++;
// Check does this inlier have consistent angles
const float maxAngleDiff = 15.f; // grad
float angle0 = keypoints0[matches[m].queryIdx].angle;
float angle1 = keypoints1[matches[m].trainIdx].angle;
if(angle0 == -1 || angle1 == -1)
CV_Error(CV_StsBadArg, "Given FeatureDetector is not rotation invariant, it can not be tested here.\n");
CV_Assert(angle0 >= 0.f && angle0 < 360.f);
CV_Assert(angle1 >= 0.f && angle1 < 360.f);
float rotAngle0 = angle0 + angle;
if(rotAngle0 >= 360.f)
rotAngle0 -= 360.f;
float angleDiff = std::max(rotAngle0, angle1) - std::min(rotAngle0, angle1);
angleDiff = std::min(angleDiff, static_cast<float>(360.f - angleDiff));
CV_Assert(angleDiff >= 0.f);
bool isAngleCorrect = angleDiff < maxAngleDiff;
if(isAngleCorrect)
angleInliersCount++;
}
float keyPointMatchesRatio = static_cast<float>(keyPointMatchesCount) / keypoints0.size();
if(keyPointMatchesRatio < minKeyPointMatchesRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect keyPointMatchesRatio: curr = %f, min = %f.\n",
keyPointMatchesRatio, minKeyPointMatchesRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
if(keyPointMatchesCount)
{
float angleInliersRatio = static_cast<float>(angleInliersCount) / keyPointMatchesCount;
if(angleInliersRatio < minAngleInliersRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect angleInliersRatio: curr = %f, min = %f.\n",
angleInliersRatio, minAngleInliersRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
}
#if SHOW_DEBUG_LOG
std::cout << "keyPointMatchesRatio - " << keyPointMatchesRatio
<< " - angleInliersRatio " << static_cast<float>(angleInliersCount) / keyPointMatchesCount << std::endl;
#endif
}
ts->set_failed_test_info( cvtest::TS::OK );
}
Ptr<FeatureDetector> featureDetector;
float minKeyPointMatchesRatio;
float minAngleInliersRatio;
};
class DescriptorRotationInvarianceTest : public cvtest::BaseTest
{
public:
DescriptorRotationInvarianceTest(const Ptr<FeatureDetector>& _featureDetector,
const Ptr<DescriptorExtractor>& _descriptorExtractor,
int _normType,
float _minDescInliersRatio) :
featureDetector(_featureDetector),
descriptorExtractor(_descriptorExtractor),
normType(_normType),
minDescInliersRatio(_minDescInliersRatio)
{
CV_Assert(!featureDetector.empty());
CV_Assert(!descriptorExtractor.empty());
}
protected:
void run(int)
{
const string imageFilename = string(ts->get_data_path()) + IMAGE_TSUKUBA;
// Read test data
Mat image0 = imread(imageFilename), image1, mask1;
if(image0.empty())
{
ts->printf(cvtest::TS::LOG, "Image %s can not be read.\n", imageFilename.c_str());
ts->set_failed_test_info(cvtest::TS::FAIL_INVALID_TEST_DATA);
return;
}
vector<KeyPoint> keypoints0;
Mat descriptors0;
featureDetector->detect(image0, keypoints0);
removeVerySmallKeypoints(keypoints0);
if(keypoints0.size() < 15)
CV_Error(CV_StsAssert, "Detector gives too few points in a test image\n");
descriptorExtractor->compute(image0, keypoints0, descriptors0);
BFMatcher bfmatcher(normType);
const float minIntersectRatio = 0.5f;
const int maxAngle = 360, angleStep = 15;
for(int angle = 0; angle < maxAngle; angle += angleStep)
{
Mat H = rotateImage(image0, static_cast<float>(angle), image1, mask1);
vector<KeyPoint> keypoints1;
rotateKeyPoints(keypoints0, H, static_cast<float>(angle), keypoints1);
Mat descriptors1;
descriptorExtractor->compute(image1, keypoints1, descriptors1);
vector<DMatch> descMatches;
bfmatcher.match(descriptors0, descriptors1, descMatches);
int descInliersCount = 0;
for(size_t m = 0; m < descMatches.size(); m++)
{
const KeyPoint& transformed_p0 = keypoints1[descMatches[m].queryIdx];
const KeyPoint& p1 = keypoints1[descMatches[m].trainIdx];
if(calcIntersectRatio(transformed_p0.pt, 0.5f * transformed_p0.size,
p1.pt, 0.5f * p1.size) >= minIntersectRatio)
{
descInliersCount++;
}
}
float descInliersRatio = static_cast<float>(descInliersCount) / keypoints0.size();
if(descInliersRatio < minDescInliersRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect descInliersRatio: curr = %f, min = %f.\n",
descInliersRatio, minDescInliersRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
#if SHOW_DEBUG_LOG
std::cout << "descInliersRatio " << static_cast<float>(descInliersCount) / keypoints0.size() << std::endl;
#endif
}
ts->set_failed_test_info( cvtest::TS::OK );
}
Ptr<FeatureDetector> featureDetector;
Ptr<DescriptorExtractor> descriptorExtractor;
int normType;
float minDescInliersRatio;
};
class DetectorScaleInvarianceTest : public cvtest::BaseTest
{
public:
DetectorScaleInvarianceTest(const Ptr<FeatureDetector>& _featureDetector,
float _minKeyPointMatchesRatio,
float _minScaleInliersRatio) :
featureDetector(_featureDetector),
minKeyPointMatchesRatio(_minKeyPointMatchesRatio),
minScaleInliersRatio(_minScaleInliersRatio)
{
CV_Assert(!featureDetector.empty());
}
protected:
void run(int)
{
const string imageFilename = string(ts->get_data_path()) + IMAGE_BIKES;
// Read test data
Mat image0 = imread(imageFilename);
if(image0.empty())
{
ts->printf(cvtest::TS::LOG, "Image %s can not be read.\n", imageFilename.c_str());
ts->set_failed_test_info(cvtest::TS::FAIL_INVALID_TEST_DATA);
return;
}
vector<KeyPoint> keypoints0;
featureDetector->detect(image0, keypoints0);
removeVerySmallKeypoints(keypoints0);
if(keypoints0.size() < 15)
CV_Error(CV_StsAssert, "Detector gives too few points in a test image\n");
for(int scaleIdx = 1; scaleIdx <= 3; scaleIdx++)
{
float scale = 1.f + scaleIdx * 0.5f;
Mat image1;
resize(image0, image1, Size(), 1./scale, 1./scale);
vector<KeyPoint> keypoints1, osiKeypoints1; // osi - original size image
featureDetector->detect(image1, keypoints1);
removeVerySmallKeypoints(keypoints1);
if(keypoints1.size() < 15)
CV_Error(CV_StsAssert, "Detector gives too few points in a test image\n");
if(keypoints1.size() > keypoints0.size())
{
ts->printf(cvtest::TS::LOG, "Strange behavior of the detector. "
"It gives more points count in an image of the smaller size.\n"
"original size (%d, %d), keypoints count = %d\n"
"reduced size (%d, %d), keypoints count = %d\n",
image0.cols, image0.rows, keypoints0.size(),
image1.cols, image1.rows, keypoints1.size());
ts->set_failed_test_info(cvtest::TS::FAIL_INVALID_OUTPUT);
return;
}
scaleKeyPoints(keypoints1, osiKeypoints1, scale);
vector<DMatch> matches;
// image1 is query image (it's reduced image0)
// image0 is train image
matchKeyPoints(osiKeypoints1, Mat(), keypoints0, matches);
const float minIntersectRatio = 0.5f;
int keyPointMatchesCount = 0;
int scaleInliersCount = 0;
for(size_t m = 0; m < matches.size(); m++)
{
if(matches[m].distance < minIntersectRatio)
continue;
keyPointMatchesCount++;
// Check does this inlier have consistent sizes
const float maxSizeDiff = 0.8f;//0.9f; // grad
float size0 = keypoints0[matches[m].trainIdx].size;
float size1 = osiKeypoints1[matches[m].queryIdx].size;
CV_Assert(size0 > 0 && size1 > 0);
if(std::min(size0, size1) > maxSizeDiff * std::max(size0, size1))
scaleInliersCount++;
}
float keyPointMatchesRatio = static_cast<float>(keyPointMatchesCount) / keypoints1.size();
if(keyPointMatchesRatio < minKeyPointMatchesRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect keyPointMatchesRatio: curr = %f, min = %f.\n",
keyPointMatchesRatio, minKeyPointMatchesRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
if(keyPointMatchesCount)
{
float scaleInliersRatio = static_cast<float>(scaleInliersCount) / keyPointMatchesCount;
if(scaleInliersRatio < minScaleInliersRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect scaleInliersRatio: curr = %f, min = %f.\n",
scaleInliersRatio, minScaleInliersRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
}
#if SHOW_DEBUG_LOG
std::cout << "keyPointMatchesRatio - " << keyPointMatchesRatio
<< " - scaleInliersRatio " << static_cast<float>(scaleInliersCount) / keyPointMatchesCount << std::endl;
#endif
}
ts->set_failed_test_info( cvtest::TS::OK );
}
Ptr<FeatureDetector> featureDetector;
float minKeyPointMatchesRatio;
float minScaleInliersRatio;
};
class DescriptorScaleInvarianceTest : public cvtest::BaseTest
{
public:
DescriptorScaleInvarianceTest(const Ptr<FeatureDetector>& _featureDetector,
const Ptr<DescriptorExtractor>& _descriptorExtractor,
int _normType,
float _minDescInliersRatio) :
featureDetector(_featureDetector),
descriptorExtractor(_descriptorExtractor),
normType(_normType),
minDescInliersRatio(_minDescInliersRatio)
{
CV_Assert(!featureDetector.empty());
CV_Assert(!descriptorExtractor.empty());
}
protected:
void run(int)
{
const string imageFilename = string(ts->get_data_path()) + IMAGE_BIKES;
// Read test data
Mat image0 = imread(imageFilename);
if(image0.empty())
{
ts->printf(cvtest::TS::LOG, "Image %s can not be read.\n", imageFilename.c_str());
ts->set_failed_test_info(cvtest::TS::FAIL_INVALID_TEST_DATA);
return;
}
vector<KeyPoint> keypoints0;
featureDetector->detect(image0, keypoints0);
removeVerySmallKeypoints(keypoints0);
if(keypoints0.size() < 15)
CV_Error(CV_StsAssert, "Detector gives too few points in a test image\n");
Mat descriptors0;
descriptorExtractor->compute(image0, keypoints0, descriptors0);
BFMatcher bfmatcher(normType);
for(int scaleIdx = 1; scaleIdx <= 3; scaleIdx++)
{
float scale = 1.f + scaleIdx * 0.5f;
Mat image1;
resize(image0, image1, Size(), 1./scale, 1./scale);
vector<KeyPoint> keypoints1;
scaleKeyPoints(keypoints0, keypoints1, 1.0f/scale);
Mat descriptors1;
descriptorExtractor->compute(image1, keypoints1, descriptors1);
vector<DMatch> descMatches;
bfmatcher.match(descriptors0, descriptors1, descMatches);
const float minIntersectRatio = 0.5f;
int descInliersCount = 0;
for(size_t m = 0; m < descMatches.size(); m++)
{
const KeyPoint& transformed_p0 = keypoints0[descMatches[m].queryIdx];
const KeyPoint& p1 = keypoints0[descMatches[m].trainIdx];
if(calcIntersectRatio(transformed_p0.pt, 0.5f * transformed_p0.size,
p1.pt, 0.5f * p1.size) >= minIntersectRatio)
{
descInliersCount++;
}
}
float descInliersRatio = static_cast<float>(descInliersCount) / keypoints0.size();
if(descInliersRatio < minDescInliersRatio)
{
ts->printf(cvtest::TS::LOG, "Incorrect descInliersRatio: curr = %f, min = %f.\n",
descInliersRatio, minDescInliersRatio);
ts->set_failed_test_info(cvtest::TS::FAIL_BAD_ACCURACY);
return;
}
#if SHOW_DEBUG_LOG
std::cout << "descInliersRatio " << static_cast<float>(descInliersCount) / keypoints0.size() << std::endl;
#endif
}
ts->set_failed_test_info( cvtest::TS::OK );
}
Ptr<FeatureDetector> featureDetector;
Ptr<DescriptorExtractor> descriptorExtractor;
int normType;
float minKeyPointMatchesRatio;
float minDescInliersRatio;
};
// Tests registration
/*
* Detector's rotation invariance check
*/
TEST(Features2d_RotationInvariance_Detector_SURF, regression)
{
DetectorRotationInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SURF"),
0.44f,
0.76f);
test.safe_run();
}
TEST(Features2d_RotationInvariance_Detector_SIFT, regression)
{
DetectorRotationInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SIFT"),
0.45f,
0.70f);
test.safe_run();
}
/*
* Descriptors's rotation invariance check
*/
TEST(Features2d_RotationInvariance_Descriptor_SURF, regression)
{
DescriptorRotationInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SURF"),
Algorithm::create<DescriptorExtractor>("Feature2D.SURF"),
NORM_L1,
0.83f);
test.safe_run();
}
TEST(Features2d_RotationInvariance_Descriptor_SIFT, regression)
{
DescriptorRotationInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SIFT"),
Algorithm::create<DescriptorExtractor>("Feature2D.SIFT"),
NORM_L1,
0.98f);
test.safe_run();
}
/*
* Detector's scale invariance check
*/
TEST(Features2d_ScaleInvariance_Detector_SURF, regression)
{
DetectorScaleInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SURF"),
0.64f,
0.84f);
test.safe_run();
}
TEST(Features2d_ScaleInvariance_Detector_SIFT, regression)
{
DetectorScaleInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SIFT"),
0.69f,
0.99f);
test.safe_run();
}
/*
* Descriptor's scale invariance check
*/
TEST(Features2d_ScaleInvariance_Descriptor_SURF, regression)
{
DescriptorScaleInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SURF"),
Algorithm::create<DescriptorExtractor>("Feature2D.SURF"),
NORM_L1,
0.61f);
test.safe_run();
}
TEST(Features2d_ScaleInvariance_Descriptor_SIFT, regression)
{
DescriptorScaleInvarianceTest test(Algorithm::create<FeatureDetector>("Feature2D.SIFT"),
Algorithm::create<DescriptorExtractor>("Feature2D.SIFT"),
NORM_L1,
0.78f);
test.safe_run();
}
TEST(Features2d_RotationInvariance2_Detector_SURF, regression)
{
Mat cross(100, 100, CV_8UC1, Scalar(255));
line(cross, Point(30, 50), Point(69, 50), Scalar(100), 3);
line(cross, Point(50, 30), Point(50, 69), Scalar(100), 3);
SURF surf(8000., 3, 4, true, false);
vector<KeyPoint> keypoints;
surf(cross, noArray(), keypoints);
ASSERT_EQ(keypoints.size(), (vector<KeyPoint>::size_type) 5);
ASSERT_LT( fabs(keypoints[1].response - keypoints[2].response), 1e-6);
ASSERT_LT( fabs(keypoints[1].response - keypoints[3].response), 1e-6);
ASSERT_LT( fabs(keypoints[1].response - keypoints[4].response), 1e-6);
}