Merge pull request #17907 from Yosshi999:gsoc_asift-py2cpp

* Implement ASIFT in C++

* '>>' should be '> >' within a nested template

* add a sample for asift usage

* bugfix empty keypoints cause crash

* simpler initialization for mask

* suppress the number of lines

* correct tex document

* type casting

* add descriptorsize for asift

* smaller testdata for asift

* more smaller test data

* add OpenCV short license header
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@ -584,6 +584,16 @@
pages = {1033--1040},
publisher = {IEEE}
}
@article{YM11,
author = {Yu, Guoshen and Morel, Jean-Michel},
title = {ASIFT: An Algorithm for Fully Affine Invariant Comparison},
year = {2011},
pages = {11--38},
journal = {Image Processing On Line},
volume = {1},
doi = {10.5201/ipol.2011.my-asift},
url = {http://www.ipol.im/pub/algo/my_affine_sift/}
}
@inproceedings{LCS11,
author = {Leutenegger, Stefan and Chli, Margarita and Siegwart, Roland Yves},
title = {BRISK: Binary robust invariant scalable keypoints},

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@ -245,6 +245,31 @@ typedef Feature2D DescriptorExtractor;
//! @{
/** @brief Class for implementing the wrapper which makes detectors and extractors to be affine invariant,
described as ASIFT in @cite YM11 .
*/
class CV_EXPORTS_W AffineFeature : public Feature2D
{
public:
/**
@param backend The detector/extractor you want to use as backend.
@param maxTilt The highest power index of tilt factor. 5 is used in the paper as tilt sampling range n.
@param minTilt The lowest power index of tilt factor. 0 is used in the paper.
@param tiltStep Tilt sampling step \f$\delta_t\f$ in Algorithm 1 in the paper.
@param rotateStepBase Rotation sampling step factor b in Algorithm 1 in the paper.
*/
CV_WRAP static Ptr<AffineFeature> create(const Ptr<Feature2D>& backend,
int maxTilt = 5, int minTilt = 0, float tiltStep = 1.4142135623730951f, float rotateStepBase = 72);
CV_WRAP virtual void setViewParams(const std::vector<float>& tilts, const std::vector<float>& rolls) = 0;
CV_WRAP virtual void getViewParams(std::vector<float>& tilts, std::vector<float>& rolls) const = 0;
CV_WRAP virtual String getDefaultName() const CV_OVERRIDE;
};
typedef AffineFeature AffineFeatureDetector;
typedef AffineFeature AffineDescriptorExtractor;
/** @brief Class for extracting keypoints and computing descriptors using the Scale Invariant Feature Transform
(SIFT) algorithm by D. Lowe @cite Lowe04 .
*/

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@ -0,0 +1,358 @@
// 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.
//
// This file is based on code issued with the following license.
/*********************************************************************
* Software License Agreement (BSD License)
*
* Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
* Copyright (C) 2008-2013, Willow Garage Inc., all rights reserved.
* Copyright (C) 2013, Evgeny Toropov, all rights reserved.
* Third party copyrights are property of their respective owners.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
* * The name of the copyright holders may not be used to endorse
* or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*********************************************************************/
/*
Guoshen Yu, Jean-Michel Morel, ASIFT: An Algorithm for Fully Affine
Invariant Comparison, Image Processing On Line, 1 (2011), pp. 1138.
https://doi.org/10.5201/ipol.2011.my-asift
*/
#include "precomp.hpp"
#include <iostream>
namespace cv {
class AffineFeature_Impl CV_FINAL : public AffineFeature
{
public:
explicit AffineFeature_Impl(const Ptr<Feature2D>& backend,
int maxTilt, int minTilt, float tiltStep, float rotateStepBase);
int descriptorSize() const CV_OVERRIDE
{
return backend_->descriptorSize();
}
int descriptorType() const CV_OVERRIDE
{
return backend_->descriptorType();
}
int defaultNorm() const CV_OVERRIDE
{
return backend_->defaultNorm();
}
void detectAndCompute(InputArray image, InputArray mask, std::vector<KeyPoint>& keypoints,
OutputArray descriptors, bool useProvidedKeypoints=false) CV_OVERRIDE;
void setViewParams(const std::vector<float>& tilts, const std::vector<float>& rolls) CV_OVERRIDE;
void getViewParams(std::vector<float>& tilts, std::vector<float>& rolls) const CV_OVERRIDE;
protected:
void splitKeypointsByView(const std::vector<KeyPoint>& keypoints_,
std::vector< std::vector<KeyPoint> >& keypointsByView) const;
const Ptr<Feature2D> backend_;
int maxTilt_;
int minTilt_;
float tiltStep_;
float rotateStepBase_;
// Tilt factors.
std::vector<float> tilts_;
// Roll factors.
std::vector<float> rolls_;
private:
AffineFeature_Impl(const AffineFeature_Impl &); // copy disabled
AffineFeature_Impl& operator=(const AffineFeature_Impl &); // assign disabled
};
AffineFeature_Impl::AffineFeature_Impl(const Ptr<FeatureDetector>& backend,
int maxTilt, int minTilt, float tiltStep, float rotateStepBase)
: backend_(backend), maxTilt_(maxTilt), minTilt_(minTilt), tiltStep_(tiltStep), rotateStepBase_(rotateStepBase)
{
int i = minTilt_;
if( i == 0 )
{
tilts_.push_back(1);
rolls_.push_back(0);
i++;
}
float tilt = 1;
for( ; i <= maxTilt_; i++ )
{
tilt *= tiltStep_;
float rotateStep = rotateStepBase_ / tilt;
int rollN = cvFloor(180.0f / rotateStep);
if( rollN * rotateStep == 180.0f )
rollN--;
for( int j = 0; j <= rollN; j++ )
{
tilts_.push_back(tilt);
rolls_.push_back(rotateStep * j);
}
}
}
void AffineFeature_Impl::setViewParams(const std::vector<float>& tilts,
const std::vector<float>& rolls)
{
CV_Assert(tilts.size() == rolls.size());
tilts_ = tilts;
rolls_ = rolls;
}
void AffineFeature_Impl::getViewParams(std::vector<float>& tilts,
std::vector<float>& rolls) const
{
tilts = tilts_;
rolls = rolls_;
}
void AffineFeature_Impl::splitKeypointsByView(const std::vector<KeyPoint>& keypoints_,
std::vector< std::vector<KeyPoint> >& keypointsByView) const
{
for( size_t i = 0; i < keypoints_.size(); i++ )
{
const KeyPoint& kp = keypoints_[i];
CV_Assert( kp.class_id >= 0 && kp.class_id < (int)tilts_.size() );
keypointsByView[kp.class_id].push_back(kp);
}
}
class skewedDetectAndCompute : public ParallelLoopBody
{
public:
skewedDetectAndCompute(
const std::vector<float>& _tilts,
const std::vector<float>& _rolls,
std::vector< std::vector<KeyPoint> >& _keypointsCollection,
std::vector<Mat>& _descriptorCollection,
const Mat& _image,
const Mat& _mask,
const bool _do_keypoints,
const bool _do_descriptors,
const Ptr<Feature2D>& _backend)
: tilts(_tilts),
rolls(_rolls),
keypointsCollection(_keypointsCollection),
descriptorCollection(_descriptorCollection),
image(_image),
mask(_mask),
do_keypoints(_do_keypoints),
do_descriptors(_do_descriptors),
backend(_backend) {}
void operator()( const cv::Range& range ) const CV_OVERRIDE
{
CV_TRACE_FUNCTION();
const int begin = range.start;
const int end = range.end;
for( int a = begin; a < end; a++ )
{
Mat warpedImage, warpedMask;
Matx23f pose, invPose;
affineSkew(tilts[a], rolls[a], warpedImage, warpedMask, pose);
invertAffineTransform(pose, invPose);
std::vector<KeyPoint> wKeypoints;
Mat wDescriptors;
if( !do_keypoints )
{
const std::vector<KeyPoint>& keypointsInView = keypointsCollection[a];
if( keypointsInView.size() == 0 ) // when there are no keypoints in this affine view
continue;
std::vector<Point2f> pts_, pts;
KeyPoint::convert(keypointsInView, pts_);
transform(pts_, pts, pose);
wKeypoints.resize(keypointsInView.size());
for( size_t wi = 0; wi < wKeypoints.size(); wi++ )
{
wKeypoints[wi] = keypointsInView[wi];
wKeypoints[wi].pt = pts[wi];
}
}
backend->detectAndCompute(warpedImage, warpedMask, wKeypoints, wDescriptors, !do_keypoints);
if( do_keypoints )
{
// KeyPointsFilter::runByPixelsMask( wKeypoints, warpedMask );
if( wKeypoints.size() == 0 )
{
keypointsCollection[a].clear();
continue;
}
std::vector<Point2f> pts_, pts;
KeyPoint::convert(wKeypoints, pts_);
transform(pts_, pts, invPose);
keypointsCollection[a].resize(wKeypoints.size());
for( size_t wi = 0; wi < wKeypoints.size(); wi++ )
{
keypointsCollection[a][wi] = wKeypoints[wi];
keypointsCollection[a][wi].pt = pts[wi];
keypointsCollection[a][wi].class_id = a;
}
}
if( do_descriptors )
wDescriptors.copyTo(descriptorCollection[a]);
}
}
private:
void affineSkew(float tilt, float phi,
Mat& warpedImage, Mat& warpedMask, Matx23f& pose) const
{
int h = image.size().height;
int w = image.size().width;
Mat rotImage;
Mat mask0;
if( mask.empty() )
mask0 = Mat(h, w, CV_8UC1, 255);
else
mask0 = mask;
pose = Matx23f(1,0,0,
0,1,0);
if( phi == 0 )
image.copyTo(rotImage);
else
{
phi = phi * (float)CV_PI / 180;
float s = std::sin(phi);
float c = std::cos(phi);
Matx22f A(c, -s, s, c);
Matx<float, 4, 2> corners(0, 0, (float)w, 0, (float)w,(float)h, 0, (float)h);
Mat tf(corners * A.t());
Mat tcorners;
tf.convertTo(tcorners, CV_32S);
Rect rect = boundingRect(tcorners);
h = rect.height; w = rect.width;
pose = Matx23f(c, -s, -(float)rect.x,
s, c, -(float)rect.y);
warpAffine(image, rotImage, pose, Size(w, h), INTER_LINEAR, BORDER_REPLICATE);
}
if( tilt == 1 )
warpedImage = rotImage;
else
{
float s = 0.8f * sqrt(tilt * tilt - 1);
GaussianBlur(rotImage, rotImage, Size(0, 0), s, 0.01);
resize(rotImage, warpedImage, Size(0, 0), 1.0/tilt, 1.0, INTER_NEAREST);
pose(0, 0) /= tilt;
pose(0, 1) /= tilt;
pose(0, 2) /= tilt;
}
if( phi != 0 || tilt != 1 )
warpAffine(mask0, warpedMask, pose, warpedImage.size(), INTER_NEAREST);
}
const std::vector<float>& tilts;
const std::vector<float>& rolls;
std::vector< std::vector<KeyPoint> >& keypointsCollection;
std::vector<Mat>& descriptorCollection;
const Mat& image;
const Mat& mask;
const bool do_keypoints;
const bool do_descriptors;
const Ptr<Feature2D>& backend;
};
void AffineFeature_Impl::detectAndCompute(InputArray _image, InputArray _mask,
std::vector<KeyPoint>& keypoints,
OutputArray _descriptors,
bool useProvidedKeypoints)
{
CV_TRACE_FUNCTION();
bool do_keypoints = !useProvidedKeypoints;
bool do_descriptors = _descriptors.needed();
Mat image = _image.getMat(), mask = _mask.getMat();
Mat descriptors;
if( (!do_keypoints && !do_descriptors) || _image.empty() )
return;
std::vector< std::vector<KeyPoint> > keypointsCollection(tilts_.size());
std::vector< Mat > descriptorCollection(tilts_.size());
if( do_keypoints )
keypoints.clear();
else
splitKeypointsByView(keypoints, keypointsCollection);
parallel_for_(Range(0, (int)tilts_.size()), skewedDetectAndCompute(tilts_, rolls_, keypointsCollection, descriptorCollection,
image, mask, do_keypoints, do_descriptors, backend_));
if( do_keypoints )
for( size_t i = 0; i < keypointsCollection.size(); i++ )
{
const std::vector<KeyPoint>& keys = keypointsCollection[i];
keypoints.insert(keypoints.end(), keys.begin(), keys.end());
}
if( do_descriptors )
{
_descriptors.create((int)keypoints.size(), backend_->descriptorSize(), backend_->descriptorType());
descriptors = _descriptors.getMat();
int iter = 0;
for( size_t i = 0; i < descriptorCollection.size(); i++ )
{
const Mat& descs = descriptorCollection[i];
if( descs.empty() )
continue;
Mat roi(descriptors, Rect(0, iter, descriptors.cols, descs.rows));
descs.copyTo(roi);
iter += descs.rows;
}
}
}
Ptr<AffineFeature> AffineFeature::create(const Ptr<Feature2D>& backend,
int maxTilt, int minTilt, float tiltStep, float rotateStepBase)
{
CV_Assert(minTilt < maxTilt);
CV_Assert(tiltStep > 0);
CV_Assert(rotateStepBase > 0);
return makePtr<AffineFeature_Impl>(backend, maxTilt, minTilt, tiltStep, rotateStepBase);
}
String AffineFeature::getDefaultName() const
{
return (Feature2D::getDefaultName() + ".AffineFeature");
}
} // namespace

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@ -0,0 +1,185 @@
// 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"
// #define GENERATE_DATA // generate data in debug mode
namespace opencv_test { namespace {
#ifndef GENERATE_DATA
static bool isSimilarKeypoints( const KeyPoint& p1, const KeyPoint& p2 )
{
const float maxPtDif = 1.f;
const float maxSizeDif = 1.f;
const float maxAngleDif = 2.f;
const float maxResponseDif = 0.1f;
float dist = (float)cv::norm( p1.pt - p2.pt );
return (dist < maxPtDif &&
fabs(p1.size - p2.size) < maxSizeDif &&
abs(p1.angle - p2.angle) < maxAngleDif &&
abs(p1.response - p2.response) < maxResponseDif &&
(p1.octave & 0xffff) == (p2.octave & 0xffff) // do not care about sublayers and class_id
);
}
#endif
TEST(Features2d_AFFINE_FEATURE, regression)
{
Mat image = imread(cvtest::findDataFile("features2d/tsukuba.png"));
string xml = cvtest::TS::ptr()->get_data_path() + "asift/regression_cpp.xml.gz";
ASSERT_FALSE(image.empty());
Mat gray;
cvtColor(image, gray, COLOR_BGR2GRAY);
// Default ASIFT generates too large descriptors. This test uses small maxTilt to suppress the size of testdata.
Ptr<AffineFeature> ext = AffineFeature::create(SIFT::create(), 2, 0, 1.4142135623730951f, 144.0f);
Mat mpt, msize, mangle, mresponse, moctave, mclass_id;
#ifdef GENERATE_DATA
// calculate
vector<KeyPoint> calcKeypoints;
Mat calcDescriptors;
ext->detectAndCompute(gray, Mat(), calcKeypoints, calcDescriptors, false);
// create keypoints XML
FileStorage fs(xml, FileStorage::WRITE);
ASSERT_TRUE(fs.isOpened()) << xml;
std::cout << "Creating keypoints XML..." << std::endl;
mpt = Mat(calcKeypoints.size(), 2, CV_32F);
msize = Mat(calcKeypoints.size(), 1, CV_32F);
mangle = Mat(calcKeypoints.size(), 1, CV_32F);
mresponse = Mat(calcKeypoints.size(), 1, CV_32F);
moctave = Mat(calcKeypoints.size(), 1, CV_32S);
mclass_id = Mat(calcKeypoints.size(), 1, CV_32S);
for( size_t i = 0; i < calcKeypoints.size(); i++ )
{
const KeyPoint& key = calcKeypoints[i];
mpt.at<float>(i, 0) = key.pt.x;
mpt.at<float>(i, 1) = key.pt.y;
msize.at<float>(i, 0) = key.size;
mangle.at<float>(i, 0) = key.angle;
mresponse.at<float>(i, 0) = key.response;
moctave.at<int>(i, 0) = key.octave;
mclass_id.at<int>(i, 0) = key.class_id;
}
fs << "keypoints_pt" << mpt;
fs << "keypoints_size" << msize;
fs << "keypoints_angle" << mangle;
fs << "keypoints_response" << mresponse;
fs << "keypoints_octave" << moctave;
fs << "keypoints_class_id" << mclass_id;
// create descriptor XML
fs << "descriptors" << calcDescriptors;
fs.release();
#else
const float badCountsRatio = 0.01f;
const float badDescriptorDist = 1.0f;
const float maxBadKeypointsRatio = 0.15f;
const float maxBadDescriptorRatio = 0.15f;
// read keypoints
vector<KeyPoint> validKeypoints;
Mat validDescriptors;
FileStorage fs(xml, FileStorage::READ);
ASSERT_TRUE(fs.isOpened()) << xml;
fs["keypoints_pt"] >> mpt;
ASSERT_EQ(mpt.type(), CV_32F);
fs["keypoints_size"] >> msize;
ASSERT_EQ(msize.type(), CV_32F);
fs["keypoints_angle"] >> mangle;
ASSERT_EQ(mangle.type(), CV_32F);
fs["keypoints_response"] >> mresponse;
ASSERT_EQ(mresponse.type(), CV_32F);
fs["keypoints_octave"] >> moctave;
ASSERT_EQ(moctave.type(), CV_32S);
fs["keypoints_class_id"] >> mclass_id;
ASSERT_EQ(mclass_id.type(), CV_32S);
validKeypoints.resize(mpt.rows);
for( int i = 0; i < (int)validKeypoints.size(); i++ )
{
validKeypoints[i].pt.x = mpt.at<float>(i, 0);
validKeypoints[i].pt.y = mpt.at<float>(i, 1);
validKeypoints[i].size = msize.at<float>(i, 0);
validKeypoints[i].angle = mangle.at<float>(i, 0);
validKeypoints[i].response = mresponse.at<float>(i, 0);
validKeypoints[i].octave = moctave.at<int>(i, 0);
validKeypoints[i].class_id = mclass_id.at<int>(i, 0);
}
// read descriptors
fs["descriptors"] >> validDescriptors;
fs.release();
// calc and compare keypoints
vector<KeyPoint> calcKeypoints;
ext->detectAndCompute(gray, Mat(), calcKeypoints, noArray(), false);
float countRatio = (float)validKeypoints.size() / (float)calcKeypoints.size();
ASSERT_LT(countRatio, 1 + badCountsRatio) << "Bad keypoints count ratio.";
ASSERT_GT(countRatio, 1 - badCountsRatio) << "Bad keypoints count ratio.";
int badPointCount = 0, commonPointCount = max((int)validKeypoints.size(), (int)calcKeypoints.size());
for( size_t v = 0; v < validKeypoints.size(); v++ )
{
int nearestIdx = -1;
float minDist = std::numeric_limits<float>::max();
float angleDistOfNearest = std::numeric_limits<float>::max();
for( size_t c = 0; c < calcKeypoints.size(); c++ )
{
if( validKeypoints[v].class_id != calcKeypoints[c].class_id )
continue;
float curDist = (float)cv::norm( calcKeypoints[c].pt - validKeypoints[v].pt );
if( curDist < minDist )
{
minDist = curDist;
nearestIdx = (int)c;
angleDistOfNearest = abs( calcKeypoints[c].angle - validKeypoints[v].angle );
}
else if( curDist == minDist ) // the keypoints whose positions are same but angles are different
{
float angleDist = abs( calcKeypoints[c].angle - validKeypoints[v].angle );
if( angleDist < angleDistOfNearest )
{
nearestIdx = (int)c;
angleDistOfNearest = angleDist;
}
}
}
if( nearestIdx == -1 || !isSimilarKeypoints( validKeypoints[v], calcKeypoints[nearestIdx] ) )
badPointCount++;
}
float badKeypointsRatio = (float)badPointCount / (float)commonPointCount;
std::cout << "badKeypointsRatio: " << badKeypointsRatio << std::endl;
ASSERT_LT( badKeypointsRatio , maxBadKeypointsRatio ) << "Bad accuracy!";
// Calc and compare descriptors. This uses validKeypoints for extraction.
Mat calcDescriptors;
ext->detectAndCompute(gray, Mat(), validKeypoints, calcDescriptors, true);
int dim = validDescriptors.cols;
int badDescriptorCount = 0;
L1<float> distance;
for( int i = 0; i < (int)validKeypoints.size(); i++ )
{
float dist = distance( validDescriptors.ptr<float>(i), calcDescriptors.ptr<float>(i), dim );
if( dist > badDescriptorDist )
badDescriptorCount++;
}
float badDescriptorRatio = (float)badDescriptorCount / (float)validKeypoints.size();
std::cout << "badDescriptorRatio: " << badDescriptorRatio << std::endl;
ASSERT_LT( badDescriptorRatio, maxBadDescriptorRatio ) << "Too many descriptors mismatched.";
#endif
}
}} // namespace

199
samples/cpp/asift.cpp Normal file
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#include <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/features2d.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/calib3d.hpp>
#include <iostream>
#include <iomanip>
using namespace std;
using namespace cv;
static void help(char** argv)
{
cout
<< "This is a sample usage of AffineFeature detector/extractor.\n"
<< "And this is a C++ version of samples/python/asift.py\n"
<< "Usage: " << argv[0] << "\n"
<< " [ --feature=<sift|orb|brisk> ] # Feature to use.\n"
<< " [ --flann ] # use Flann-based matcher instead of bruteforce.\n"
<< " [ --maxlines=<number(50 as default)> ] # The maximum number of lines in visualizing the matching result.\n"
<< " [ --image1=<image1(aero1.jpg as default)> ]\n"
<< " [ --image2=<image2(aero3.jpg as default)> ] # Path to images to compare."
<< endl;
}
static double timer()
{
return getTickCount() / getTickFrequency();
}
int main(int argc, char** argv)
{
vector<String> fileName;
cv::CommandLineParser parser(argc, argv,
"{help h ||}"
"{feature|brisk|}"
"{flann||}"
"{maxlines|50|}"
"{image1|aero1.jpg|}{image2|aero3.jpg|}");
if (parser.has("help"))
{
help(argv);
return 0;
}
string feature = parser.get<string>("feature");
bool useFlann = parser.has("flann");
int maxlines = parser.get<int>("maxlines");
fileName.push_back(samples::findFile(parser.get<string>("image1")));
fileName.push_back(samples::findFile(parser.get<string>("image2")));
if (!parser.check())
{
parser.printErrors();
cout << "See --help (or missing '=' between argument name and value?)" << endl;
return 1;
}
Mat img1 = imread(fileName[0], IMREAD_GRAYSCALE);
Mat img2 = imread(fileName[1], IMREAD_GRAYSCALE);
if (img1.empty())
{
cerr << "Image " << fileName[0] << " is empty or cannot be found" << endl;
return 1;
}
if (img2.empty())
{
cerr << "Image " << fileName[1] << " is empty or cannot be found" << endl;
return 1;
}
Ptr<Feature2D> backend;
Ptr<DescriptorMatcher> matcher;
if (feature == "sift")
{
backend = SIFT::create();
if (useFlann)
matcher = DescriptorMatcher::create("FlannBased");
else
matcher = DescriptorMatcher::create("BruteForce");
}
else if (feature == "orb")
{
backend = ORB::create();
if (useFlann)
matcher = makePtr<FlannBasedMatcher>(makePtr<flann::LshIndexParams>(6, 12, 1));
else
matcher = DescriptorMatcher::create("BruteForce-Hamming");
}
else if (feature == "brisk")
{
backend = BRISK::create();
if (useFlann)
matcher = makePtr<FlannBasedMatcher>(makePtr<flann::LshIndexParams>(6, 12, 1));
else
matcher = DescriptorMatcher::create("BruteForce-Hamming");
}
else
{
cerr << feature << " is not supported. See --help" << endl;
return 1;
}
cout << "extracting with " << feature << "..." << endl;
Ptr<AffineFeature> ext = AffineFeature::create(backend);
vector<KeyPoint> kp1, kp2;
Mat desc1, desc2;
ext->detectAndCompute(img1, Mat(), kp1, desc1);
ext->detectAndCompute(img2, Mat(), kp2, desc2);
cout << "img1 - " << kp1.size() << " features, "
<< "img2 - " << kp2.size() << " features"
<< endl;
cout << "matching with " << (useFlann ? "flann" : "bruteforce") << "..." << endl;
double start = timer();
// match and draw
vector< vector<DMatch> > rawMatches;
vector<Point2f> p1, p2;
vector<float> distances;
matcher->knnMatch(desc1, desc2, rawMatches, 2);
// filter_matches
for (size_t i = 0; i < rawMatches.size(); i++)
{
const vector<DMatch>& m = rawMatches[i];
if (m.size() == 2 && m[0].distance < m[1].distance * 0.75)
{
p1.push_back(kp1[m[0].queryIdx].pt);
p2.push_back(kp2[m[0].trainIdx].pt);
distances.push_back(m[0].distance);
}
}
vector<uchar> status;
vector< pair<Point2f, Point2f> > pointPairs;
Mat H = findHomography(p1, p2, status, RANSAC);
int inliers = 0;
for (size_t i = 0; i < status.size(); i++)
{
if (status[i])
{
pointPairs.push_back(make_pair(p1[i], p2[i]));
distances[inliers] = distances[i];
// CV_Assert(inliers <= (int)i);
inliers++;
}
}
distances.resize(inliers);
cout << "execution time: " << fixed << setprecision(2) << (timer()-start)*1000 << " ms" << endl;
cout << inliers << " / " << status.size() << " inliers/matched" << endl;
cout << "visualizing..." << endl;
vector<int> indices(inliers);
cv::sortIdx(distances, indices, SORT_EVERY_ROW+SORT_ASCENDING);
// explore_match
int h1 = img1.size().height;
int w1 = img1.size().width;
int h2 = img2.size().height;
int w2 = img2.size().width;
Mat vis = Mat::zeros(max(h1, h2), w1+w2, CV_8U);
img1.copyTo(Mat(vis, Rect(0, 0, w1, h1)));
img2.copyTo(Mat(vis, Rect(w1, 0, w2, h2)));
cvtColor(vis, vis, COLOR_GRAY2BGR);
vector<Point2f> corners(4);
corners[0] = Point2f(0, 0);
corners[1] = Point2f((float)w1, 0);
corners[2] = Point2f((float)w1, (float)h1);
corners[3] = Point2f(0, (float)h1);
vector<Point2i> icorners;
perspectiveTransform(corners, corners, H);
transform(corners, corners, Matx23f(1,0,(float)w1,0,1,0));
Mat(corners).convertTo(icorners, CV_32S);
polylines(vis, icorners, true, Scalar(255,255,255));
for (int i = 0; i < min(inliers, maxlines); i++)
{
int idx = indices[i];
const Point2f& pi1 = pointPairs[idx].first;
const Point2f& pi2 = pointPairs[idx].second;
circle(vis, pi1, 2, Scalar(0,255,0), -1);
circle(vis, pi2 + Point2f((float)w1,0), 2, Scalar(0,255,0), -1);
line(vis, pi1, pi2 + Point2f((float)w1,0), Scalar(0,255,0));
}
if (inliers > maxlines)
cout << "only " << maxlines << " inliers are visualized" << endl;
imshow("affine find_obj", vis);
// Mat vis2 = Mat::zeros(max(h1, h2), w1+w2, CV_8U);
// Mat warp1;
// warpPerspective(img1, warp1, H, Size(w1, h1));
// warp1.copyTo(Mat(vis2, Rect(0, 0, w1, h1)));
// img2.copyTo(Mat(vis2, Rect(w1, 0, w2, h2)));
// imshow("warped", vis2);
waitKey();
cout << "done" << endl;
return 0;
}