opencv/modules/contrib/src/rgbdodometry.cpp
Andrey Kamaev 2a6fb2867e Remove all using directives for STL namespace and members
Made all STL usages explicit to be able automatically find all usages of
particular class or function.
2013-02-25 15:04:17 +04:00

637 lines
22 KiB
C++

/*M///////////////////////////////////////////////////////////////////////////////////////
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#include "precomp.hpp"
#define SHOW_DEBUG_IMAGES 0
#include "opencv2/core/core.hpp"
#include "opencv2/calib3d/calib3d.hpp"
#if SHOW_DEBUG_IMAGES
# include "opencv2/highgui/highgui.hpp"
#endif
#include <iostream>
#include <limits>
#include "opencv2/core/internal.hpp"
#if defined(HAVE_EIGEN) && EIGEN_WORLD_VERSION == 3
# ifdef ANDROID
template <typename Scalar> Scalar log2(Scalar v) { return std::log(v)/std::log(Scalar(2)); }
# endif
# if defined __GNUC__ && defined __APPLE__
# pragma GCC diagnostic ignored "-Wshadow"
# endif
# include <unsupported/Eigen/MatrixFunctions>
# include <Eigen/Dense>
#endif
using namespace cv;
inline static
void computeC_RigidBodyMotion( double* C, double dIdx, double dIdy, const Point3f& p3d, double fx, double fy )
{
double invz = 1. / p3d.z,
v0 = dIdx * fx * invz,
v1 = dIdy * fy * invz,
v2 = -(v0 * p3d.x + v1 * p3d.y) * invz;
C[0] = -p3d.z * v1 + p3d.y * v2;
C[1] = p3d.z * v0 - p3d.x * v2;
C[2] = -p3d.y * v0 + p3d.x * v1;
C[3] = v0;
C[4] = v1;
C[5] = v2;
}
inline static
void computeC_Rotation( double* C, double dIdx, double dIdy, const Point3f& p3d, double fx, double fy )
{
double invz = 1. / p3d.z,
v0 = dIdx * fx * invz,
v1 = dIdy * fy * invz,
v2 = -(v0 * p3d.x + v1 * p3d.y) * invz;
C[0] = -p3d.z * v1 + p3d.y * v2;
C[1] = p3d.z * v0 - p3d.x * v2;
C[2] = -p3d.y * v0 + p3d.x * v1;
}
inline static
void computeC_Translation( double* C, double dIdx, double dIdy, const Point3f& p3d, double fx, double fy )
{
double invz = 1. / p3d.z,
v0 = dIdx * fx * invz,
v1 = dIdy * fy * invz,
v2 = -(v0 * p3d.x + v1 * p3d.y) * invz;
C[0] = v0;
C[1] = v1;
C[2] = v2;
}
inline static
void computeProjectiveMatrix( const Mat& ksi, Mat& Rt )
{
CV_Assert( ksi.size() == Size(1,6) && ksi.type() == CV_64FC1 );
#if defined(HAVE_EIGEN) && EIGEN_WORLD_VERSION == 3
const double* ksi_ptr = reinterpret_cast<const double*>(ksi.ptr(0));
Eigen::Matrix<double,4,4> twist, g;
twist << 0., -ksi_ptr[2], ksi_ptr[1], ksi_ptr[3],
ksi_ptr[2], 0., -ksi_ptr[0], ksi_ptr[4],
-ksi_ptr[1], ksi_ptr[0], 0, ksi_ptr[5],
0., 0., 0., 0.;
g = twist.exp();
eigen2cv(g, Rt);
#else
// for infinitesimal transformation
Rt = Mat::eye(4, 4, CV_64FC1);
Mat R = Rt(Rect(0,0,3,3));
Mat rvec = ksi.rowRange(0,3);
Rodrigues( rvec, R );
Rt.at<double>(0,3) = ksi.at<double>(3);
Rt.at<double>(1,3) = ksi.at<double>(4);
Rt.at<double>(2,3) = ksi.at<double>(5);
#endif
}
static
void cvtDepth2Cloud( const Mat& depth, Mat& cloud, const Mat& cameraMatrix )
{
CV_Assert( cameraMatrix.type() == CV_64FC1 );
const double inv_fx = 1.f/cameraMatrix.at<double>(0,0);
const double inv_fy = 1.f/cameraMatrix.at<double>(1,1);
const double ox = cameraMatrix.at<double>(0,2);
const double oy = cameraMatrix.at<double>(1,2);
cloud.create( depth.size(), CV_32FC3 );
for( int y = 0; y < cloud.rows; y++ )
{
Point3f* cloud_ptr = reinterpret_cast<Point3f*>(cloud.ptr(y));
const float* depth_prt = reinterpret_cast<const float*>(depth.ptr(y));
for( int x = 0; x < cloud.cols; x++ )
{
float z = depth_prt[x];
cloud_ptr[x].x = (float)((x - ox) * z * inv_fx);
cloud_ptr[x].y = (float)((y - oy) * z * inv_fy);
cloud_ptr[x].z = z;
}
}
}
#if SHOW_DEBUG_IMAGES
template<class ImageElemType>
static void warpImage( const Mat& image, const Mat& depth,
const Mat& Rt, const Mat& cameraMatrix, const Mat& distCoeff,
Mat& warpedImage )
{
const Rect rect = Rect(0, 0, image.cols, image.rows);
std::vector<Point2f> points2d;
Mat cloud, transformedCloud;
cvtDepth2Cloud( depth, cloud, cameraMatrix );
perspectiveTransform( cloud, transformedCloud, Rt );
projectPoints( transformedCloud.reshape(3,1), Mat::eye(3,3,CV_64FC1), Mat::zeros(3,1,CV_64FC1), cameraMatrix, distCoeff, points2d );
Mat pointsPositions( points2d );
pointsPositions = pointsPositions.reshape( 2, image.rows );
warpedImage.create( image.size(), image.type() );
warpedImage = Scalar::all(0);
Mat zBuffer( image.size(), CV_32FC1, FLT_MAX );
for( int y = 0; y < image.rows; y++ )
{
for( int x = 0; x < image.cols; x++ )
{
const Point3f p3d = transformedCloud.at<Point3f>(y,x);
const Point p2d = pointsPositions.at<Point2f>(y,x);
if( !cvIsNaN(cloud.at<Point3f>(y,x).z) && cloud.at<Point3f>(y,x).z > 0 &&
rect.contains(p2d) && zBuffer.at<float>(p2d) > p3d.z )
{
warpedImage.at<ImageElemType>(p2d) = image.at<ImageElemType>(y,x);
zBuffer.at<float>(p2d) = p3d.z;
}
}
}
}
#endif
static inline
void set2shorts( int& dst, int short_v1, int short_v2 )
{
unsigned short* ptr = reinterpret_cast<unsigned short*>(&dst);
ptr[0] = static_cast<unsigned short>(short_v1);
ptr[1] = static_cast<unsigned short>(short_v2);
}
static inline
void get2shorts( int src, int& short_v1, int& short_v2 )
{
typedef union { int vint32; unsigned short vuint16[2]; } s32tou16;
const unsigned short* ptr = (reinterpret_cast<s32tou16*>(&src))->vuint16;
short_v1 = ptr[0];
short_v2 = ptr[1];
}
static
int computeCorresp( const Mat& K, const Mat& K_inv, const Mat& Rt,
const Mat& depth0, const Mat& depth1, const Mat& texturedMask1, float maxDepthDiff,
Mat& corresps )
{
CV_Assert( K.type() == CV_64FC1 );
CV_Assert( K_inv.type() == CV_64FC1 );
CV_Assert( Rt.type() == CV_64FC1 );
corresps.create( depth1.size(), CV_32SC1 );
Mat R = Rt(Rect(0,0,3,3)).clone();
Mat KRK_inv = K * R * K_inv;
const double * KRK_inv_ptr = reinterpret_cast<const double *>(KRK_inv.ptr());
Mat Kt = Rt(Rect(3,0,1,3)).clone();
Kt = K * Kt;
const double * Kt_ptr = reinterpret_cast<const double *>(Kt.ptr());
Rect r(0, 0, depth1.cols, depth1.rows);
corresps = Scalar(-1);
int correspCount = 0;
for( int v1 = 0; v1 < depth1.rows; v1++ )
{
for( int u1 = 0; u1 < depth1.cols; u1++ )
{
float d1 = depth1.at<float>(v1,u1);
if( !cvIsNaN(d1) && texturedMask1.at<uchar>(v1,u1) )
{
float transformed_d1 = (float)(d1 * (KRK_inv_ptr[6] * u1 + KRK_inv_ptr[7] * v1 + KRK_inv_ptr[8]) + Kt_ptr[2]);
int u0 = cvRound((d1 * (KRK_inv_ptr[0] * u1 + KRK_inv_ptr[1] * v1 + KRK_inv_ptr[2]) + Kt_ptr[0]) / transformed_d1);
int v0 = cvRound((d1 * (KRK_inv_ptr[3] * u1 + KRK_inv_ptr[4] * v1 + KRK_inv_ptr[5]) + Kt_ptr[1]) / transformed_d1);
if( r.contains(Point(u0,v0)) )
{
float d0 = depth0.at<float>(v0,u0);
if( !cvIsNaN(d0) && std::abs(transformed_d1 - d0) <= maxDepthDiff )
{
int c = corresps.at<int>(v0,u0);
if( c != -1 )
{
int exist_u1, exist_v1;
get2shorts( c, exist_u1, exist_v1);
float exist_d1 = (float)(depth1.at<float>(exist_v1,exist_u1) * (KRK_inv_ptr[6] * exist_u1 + KRK_inv_ptr[7] * exist_v1 + KRK_inv_ptr[8]) + Kt_ptr[2]);
if( transformed_d1 > exist_d1 )
continue;
}
else
correspCount++;
set2shorts( corresps.at<int>(v0,u0), u1, v1 );
}
}
}
}
}
return correspCount;
}
static inline
void preprocessDepth( Mat depth0, Mat depth1,
const Mat& validMask0, const Mat& validMask1,
float minDepth, float maxDepth )
{
CV_DbgAssert( depth0.size() == depth1.size() );
for( int y = 0; y < depth0.rows; y++ )
{
for( int x = 0; x < depth0.cols; x++ )
{
float& d0 = depth0.at<float>(y,x);
if( !cvIsNaN(d0) && (d0 > maxDepth || d0 < minDepth || d0 <= 0 || (!validMask0.empty() && !validMask0.at<uchar>(y,x))) )
d0 = std::numeric_limits<float>::quiet_NaN();
float& d1 = depth1.at<float>(y,x);
if( !cvIsNaN(d1) && (d1 > maxDepth || d1 < minDepth || d1 <= 0 || (!validMask1.empty() && !validMask1.at<uchar>(y,x))) )
d1 = std::numeric_limits<float>::quiet_NaN();
}
}
}
static
void buildPyramids( const Mat& image0, const Mat& image1,
const Mat& depth0, const Mat& depth1,
const Mat& cameraMatrix, int sobelSize, double sobelScale,
const std::vector<float>& minGradMagnitudes,
std::vector<Mat>& pyramidImage0, std::vector<Mat>& pyramidDepth0,
std::vector<Mat>& pyramidImage1, std::vector<Mat>& pyramidDepth1,
std::vector<Mat>& pyramid_dI_dx1, std::vector<Mat>& pyramid_dI_dy1,
std::vector<Mat>& pyramidTexturedMask1, std::vector<Mat>& pyramidCameraMatrix )
{
const int pyramidMaxLevel = (int)minGradMagnitudes.size() - 1;
buildPyramid( image0, pyramidImage0, pyramidMaxLevel );
buildPyramid( image1, pyramidImage1, pyramidMaxLevel );
pyramid_dI_dx1.resize( pyramidImage1.size() );
pyramid_dI_dy1.resize( pyramidImage1.size() );
pyramidTexturedMask1.resize( pyramidImage1.size() );
pyramidCameraMatrix.reserve( pyramidImage1.size() );
Mat cameraMatrix_dbl;
cameraMatrix.convertTo( cameraMatrix_dbl, CV_64FC1 );
for( size_t i = 0; i < pyramidImage1.size(); i++ )
{
Sobel( pyramidImage1[i], pyramid_dI_dx1[i], CV_16S, 1, 0, sobelSize );
Sobel( pyramidImage1[i], pyramid_dI_dy1[i], CV_16S, 0, 1, sobelSize );
const Mat& dx = pyramid_dI_dx1[i];
const Mat& dy = pyramid_dI_dy1[i];
Mat texturedMask( dx.size(), CV_8UC1, Scalar(0) );
const float minScalesGradMagnitude2 = (float)((minGradMagnitudes[i] * minGradMagnitudes[i]) / (sobelScale * sobelScale));
for( int y = 0; y < dx.rows; y++ )
{
for( int x = 0; x < dx.cols; x++ )
{
float m2 = (float)(dx.at<short>(y,x)*dx.at<short>(y,x) + dy.at<short>(y,x)*dy.at<short>(y,x));
if( m2 >= minScalesGradMagnitude2 )
texturedMask.at<uchar>(y,x) = 255;
}
}
pyramidTexturedMask1[i] = texturedMask;
Mat levelCameraMatrix = i == 0 ? cameraMatrix_dbl : 0.5f * pyramidCameraMatrix[i-1];
levelCameraMatrix.at<double>(2,2) = 1.;
pyramidCameraMatrix.push_back( levelCameraMatrix );
}
buildPyramid( depth0, pyramidDepth0, pyramidMaxLevel );
buildPyramid( depth1, pyramidDepth1, pyramidMaxLevel );
}
static
bool solveSystem( const Mat& C, const Mat& dI_dt, double detThreshold, Mat& ksi )
{
#if defined(HAVE_EIGEN) && EIGEN_WORLD_VERSION == 3
Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic> eC, eCt, edI_dt;
cv2eigen(C, eC);
cv2eigen(dI_dt, edI_dt);
eCt = eC.transpose();
Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic> A, B, eksi;
A = eCt * eC;
double det = A.determinant();
if( fabs (det) < detThreshold || cvIsNaN(det) || cvIsInf(det) )
return false;
B = -eCt * edI_dt;
eksi = A.ldlt().solve(B);
eigen2cv( eksi, ksi );
#else
Mat A = C.t() * C;
double det = cv::determinant(A);
if( fabs (det) < detThreshold || cvIsNaN(det) || cvIsInf(det) )
return false;
Mat B = -C.t() * dI_dt;
cv::solve( A, B, ksi, DECOMP_CHOLESKY );
#endif
return true;
}
typedef void (*ComputeCFuncPtr)( double* C, double dIdx, double dIdy, const Point3f& p3d, double fx, double fy );
static
bool computeKsi( int transformType,
const Mat& image0, const Mat& cloud0,
const Mat& image1, const Mat& dI_dx1, const Mat& dI_dy1,
const Mat& corresps, int correspsCount,
double fx, double fy, double sobelScale, double determinantThreshold,
Mat& ksi )
{
int Cwidth = -1;
ComputeCFuncPtr computeCFuncPtr = 0;
if( transformType == RIGID_BODY_MOTION )
{
Cwidth = 6;
computeCFuncPtr = computeC_RigidBodyMotion;
}
else if( transformType == ROTATION )
{
Cwidth = 3;
computeCFuncPtr = computeC_Rotation;
}
else if( transformType == TRANSLATION )
{
Cwidth = 3;
computeCFuncPtr = computeC_Translation;
}
else
CV_Error( CV_StsBadFlag, "Unsupported value of transformation type flag.");
Mat C( correspsCount, Cwidth, CV_64FC1 );
Mat dI_dt( correspsCount, 1, CV_64FC1 );
double sigma = 0;
int pointCount = 0;
for( int v0 = 0; v0 < corresps.rows; v0++ )
{
for( int u0 = 0; u0 < corresps.cols; u0++ )
{
if( corresps.at<int>(v0,u0) != -1 )
{
int u1, v1;
get2shorts( corresps.at<int>(v0,u0), u1, v1 );
double diff = static_cast<double>(image1.at<uchar>(v1,u1)) -
static_cast<double>(image0.at<uchar>(v0,u0));
sigma += diff * diff;
pointCount++;
}
}
}
sigma = std::sqrt(sigma/pointCount);
pointCount = 0;
for( int v0 = 0; v0 < corresps.rows; v0++ )
{
for( int u0 = 0; u0 < corresps.cols; u0++ )
{
if( corresps.at<int>(v0,u0) != -1 )
{
int u1, v1;
get2shorts( corresps.at<int>(v0,u0), u1, v1 );
double diff = static_cast<double>(image1.at<uchar>(v1,u1)) -
static_cast<double>(image0.at<uchar>(v0,u0));
double w = sigma + std::abs(diff);
w = w > DBL_EPSILON ? 1./w : 1.;
(*computeCFuncPtr)( (double*)C.ptr(pointCount),
w * sobelScale * dI_dx1.at<short int>(v1,u1),
w * sobelScale * dI_dy1.at<short int>(v1,u1),
cloud0.at<Point3f>(v0,u0), fx, fy);
dI_dt.at<double>(pointCount) = w * diff;
pointCount++;
}
}
}
Mat sln;
bool solutionExist = solveSystem( C, dI_dt, determinantThreshold, sln );
if( solutionExist )
{
ksi.create(6,1,CV_64FC1);
ksi = Scalar(0);
Mat subksi;
if( transformType == RIGID_BODY_MOTION )
{
subksi = ksi;
}
else if( transformType == ROTATION )
{
subksi = ksi.rowRange(0,3);
}
else if( transformType == TRANSLATION )
{
subksi = ksi.rowRange(3,6);
}
sln.copyTo( subksi );
}
return solutionExist;
}
bool cv::RGBDOdometry( cv::Mat& Rt, const Mat& initRt,
const cv::Mat& image0, const cv::Mat& _depth0, const cv::Mat& validMask0,
const cv::Mat& image1, const cv::Mat& _depth1, const cv::Mat& validMask1,
const cv::Mat& cameraMatrix, float minDepth, float maxDepth, float maxDepthDiff,
const std::vector<int>& iterCounts, const std::vector<float>& minGradientMagnitudes,
int transformType )
{
const int sobelSize = 3;
const double sobelScale = 1./8;
Mat depth0 = _depth0.clone(),
depth1 = _depth1.clone();
// check RGB-D input data
CV_Assert( !image0.empty() );
CV_Assert( image0.type() == CV_8UC1 );
CV_Assert( depth0.type() == CV_32FC1 && depth0.size() == image0.size() );
CV_Assert( image1.size() == image0.size() );
CV_Assert( image1.type() == CV_8UC1 );
CV_Assert( depth1.type() == CV_32FC1 && depth1.size() == image0.size() );
// check masks
CV_Assert( validMask0.empty() || (validMask0.type() == CV_8UC1 && validMask0.size() == image0.size()) );
CV_Assert( validMask1.empty() || (validMask1.type() == CV_8UC1 && validMask1.size() == image0.size()) );
// check camera params
CV_Assert( cameraMatrix.type() == CV_32FC1 && cameraMatrix.size() == Size(3,3) );
// other checks
CV_Assert( iterCounts.empty() || minGradientMagnitudes.empty() ||
minGradientMagnitudes.size() == iterCounts.size() );
CV_Assert( initRt.empty() || (initRt.type()==CV_64FC1 && initRt.size()==Size(4,4) ) );
std::vector<int> defaultIterCounts;
std::vector<float> defaultMinGradMagnitudes;
std::vector<int> const* iterCountsPtr = &iterCounts;
std::vector<float> const* minGradientMagnitudesPtr = &minGradientMagnitudes;
if( iterCounts.empty() || minGradientMagnitudes.empty() )
{
defaultIterCounts.resize(4);
defaultIterCounts[0] = 7;
defaultIterCounts[1] = 7;
defaultIterCounts[2] = 7;
defaultIterCounts[3] = 10;
defaultMinGradMagnitudes.resize(4);
defaultMinGradMagnitudes[0] = 12;
defaultMinGradMagnitudes[1] = 5;
defaultMinGradMagnitudes[2] = 3;
defaultMinGradMagnitudes[3] = 1;
iterCountsPtr = &defaultIterCounts;
minGradientMagnitudesPtr = &defaultMinGradMagnitudes;
}
preprocessDepth( depth0, depth1, validMask0, validMask1, minDepth, maxDepth );
std::vector<Mat> pyramidImage0, pyramidDepth0,
pyramidImage1, pyramidDepth1, pyramid_dI_dx1, pyramid_dI_dy1, pyramidTexturedMask1,
pyramidCameraMatrix;
buildPyramids( image0, image1, depth0, depth1, cameraMatrix, sobelSize, sobelScale, *minGradientMagnitudesPtr,
pyramidImage0, pyramidDepth0, pyramidImage1, pyramidDepth1,
pyramid_dI_dx1, pyramid_dI_dy1, pyramidTexturedMask1, pyramidCameraMatrix );
Mat resultRt = initRt.empty() ? Mat::eye(4,4,CV_64FC1) : initRt.clone();
Mat currRt, ksi;
for( int level = (int)iterCountsPtr->size() - 1; level >= 0; level-- )
{
const Mat& levelCameraMatrix = pyramidCameraMatrix[level];
const Mat& levelImage0 = pyramidImage0[level];
const Mat& levelDepth0 = pyramidDepth0[level];
Mat levelCloud0;
cvtDepth2Cloud( pyramidDepth0[level], levelCloud0, levelCameraMatrix );
const Mat& levelImage1 = pyramidImage1[level];
const Mat& levelDepth1 = pyramidDepth1[level];
const Mat& level_dI_dx1 = pyramid_dI_dx1[level];
const Mat& level_dI_dy1 = pyramid_dI_dy1[level];
CV_Assert( level_dI_dx1.type() == CV_16S );
CV_Assert( level_dI_dy1.type() == CV_16S );
const double fx = levelCameraMatrix.at<double>(0,0);
const double fy = levelCameraMatrix.at<double>(1,1);
const double determinantThreshold = 1e-6;
Mat corresps( levelImage0.size(), levelImage0.type() );
// Run transformation search on current level iteratively.
for( int iter = 0; iter < (*iterCountsPtr)[level]; iter ++ )
{
int correspsCount = computeCorresp( levelCameraMatrix, levelCameraMatrix.inv(), resultRt.inv(DECOMP_SVD),
levelDepth0, levelDepth1, pyramidTexturedMask1[level], maxDepthDiff,
corresps );
if( correspsCount == 0 )
break;
bool solutionExist = computeKsi( transformType,
levelImage0, levelCloud0,
levelImage1, level_dI_dx1, level_dI_dy1,
corresps, correspsCount,
fx, fy, sobelScale, determinantThreshold,
ksi );
if( !solutionExist )
break;
computeProjectiveMatrix( ksi, currRt );
resultRt = currRt * resultRt;
#if SHOW_DEBUG_IMAGES
std::cout << "currRt " << currRt << std::endl;
Mat warpedImage0;
const Mat distCoeff(1,5,CV_32FC1,Scalar(0));
warpImage<uchar>( levelImage0, levelDepth0, resultRt, levelCameraMatrix, distCoeff, warpedImage0 );
imshow( "im0", levelImage0 );
imshow( "wim0", warpedImage0 );
imshow( "im1", levelImage1 );
waitKey();
#endif
}
}
Rt = resultRt;
return !Rt.empty();
}