WebSVN – seema-scanner – Diff – /src/algorithm/AlgorithmPhaseShiftTwoFreq.cpp

 //
 // Two Frequency Phase Shifting using the Heterodyne Principle
 //
 // This implementation follows "Reich, Ritter, Thesing, White light heterodyne principle for 3D-measurement", SPIE (1997)
 // Different from the paper, it uses only two different frequencies.
 //
 // The number of periods in the primary frequency can be chosen freely, but small changes can have a considerable impact on quality.
 // The number of phase shifts can be chosen freely (min. 3), and higher values reduce the effects of image noise. They also allow us to filter bad points based on energy at non-primary frequencies.
 //
 #include "AlgorithmPhaseShiftTwoFreq.h"
 #include <math.h>
 #include "cvtools.h"
 #include "algorithmtools.h"
 static unsigned int nStepsPrimary = 16; // number of shifts/steps in primary
 static unsigned int nStepsSecondary = 8; // number of shifts/steps in secondary
 static float nPeriodsPrimary = 40; // primary period
 AlgorithmPhaseShiftTwoFreq::AlgorithmPhaseShiftTwoFreq(unsigned int _screenCols, unsigned int _screenRows) : Algorithm(_screenCols, _screenRows){
     // Set N
     N = 2+nStepsPrimary+nStepsSecondary;
     // Determine the secondary (wider) period to fulfill the heterodyne condition
     float nPeriodsSecondary = nPeriodsPrimary + 1;
     // all on pattern
     cv::Mat allOn(1, screenCols, CV_8UC3, cv::Scalar::all(255));
     patterns.push_back(allOn);
     // all off pattern
     cv::Mat allOff(1, screenCols, CV_8UC3, cv::Scalar::all(0));
     patterns.push_back(allOff);
     // Primary encoding patterns
     for(unsigned int i=0; i<nStepsPrimary; i++){
         float phase = 2.0*CV_PI/nStepsPrimary * i;
         float pitch = screenCols/nPeriodsPrimary;
         cv::Mat patternI(1,1,CV_8U);
         patternI = computePhaseVector(screenCols, phase, pitch);
         patterns.push_back(patternI.t());
+    }
     // Secondary encoding patterns
     for(unsigned int i=0; i<nStepsSecondary; i++){
         float phase = 2.0*CV_PI/nStepsSecondary * i;
         float pitch = screenCols/nPeriodsSecondary;
         cv::Mat patternI(1,1,CV_8U);
         patternI = computePhaseVector(screenCols, phase, pitch);
         patterns.push_back(patternI.t());
+    }
+}
 cv::Mat AlgorithmPhaseShiftTwoFreq::getEncodingPattern(unsigned int depth){
     return patterns[depth];
+}
-void AlgorithmPhaseShiftTwoFreq::get3DPoints(SMCalibrationParameters calibration, const std::vector<cv::Mat>& frames0, const std::vector<cv::Mat>& frames1, std::vector<cv::Point3f>& Q, std::vector<cv::Vec3b>& color){
+void AlgorithmPhaseShiftTwoFreq::get3DPoints(const SMCalibrationParameters & calibration, const std::vector<cv::Mat>& frames0, const std::vector<cv::Mat>& frames1, std::vector<cv::Point3f>& Q, std::vector<cv::Vec3b>& color){
     assert(frames0.size() == N);
     assert(frames1.size() == N);
+    cv::Mat map0X, map0Y, map1X, map1Y;
+    cv::Mat R0, P0, P1;
+{
     int frameRows = frames0[0].rows;
     int frameCols = frames0[0].cols;
     // Rectifying homographies (rotation+projections)
     cv::Size frameSize(frameCols, frameRows);
     cv::Mat R, T;
     // stereoRectify segfaults unless R is double precision
     cv::Mat(calibration.R1).convertTo(R, CV_64F);
     cv::Mat(calibration.T1).convertTo(T, CV_64F);
-    cv::Mat R0, R1, P0, P1, QRect;
+    cv::Mat  R1, QRect;
     cv::stereoRectify(calibration.K0, calibration.k0, calibration.K1, calibration.k1, frameSize, R, T, R0, R1, P0, P1, QRect, 0);
     // Interpolation maps (lens distortion and rectification)
-    cv::Mat map0X, map0Y, map1X, map1Y;
     cv::initUndistortRectifyMap(calibration.K0, calibration.k0, R0, P0, frameSize, CV_32F, map0X, map0Y);
     cv::initUndistortRectifyMap(calibration.K1, calibration.k1, R1, P1, frameSize, CV_32F, map1X, map1Y);
+    }
     int frameRectRows = map0X.rows;
     int frameRectCols = map0X.cols;
+    cv::Mat up0;
-    // Gray-scale and remap
+    cv::Mat occlusion0;
+{
-    std::vector<cv::Mat> frames0Rect(N);
+        // Gray-scale and remap
-    std::vector<cv::Mat> frames1Rect(N);
+        std::vector<cv::Mat> frames0Rect(N);
-    for(unsigned int i=0; i<N; i++){
+        for(unsigned int i=0; i<N; i++){
-        cv::Mat temp;
+            cv::Mat temp;
-        cv::cvtColor(frames0[i], temp, CV_BayerBG2GRAY);
+            cv::cvtColor(frames0[i], temp, CV_BayerBG2GRAY);
-        cv::remap(temp, frames0Rect[i], map0X, map0Y, CV_INTER_LINEAR);
+            cv::remap(temp, frames0Rect[i], map0X, map0Y, CV_INTER_LINEAR);
+        }
+        // Occlusion masks
-        cv::cvtColor(frames1[i], temp, CV_BayerBG2GRAY);
+        cv::subtract(frames0Rect[0], frames0Rect[1], occlusion0);
-        cv::remap(temp, frames1Rect[i], map1X, map1Y, CV_INTER_LINEAR);
+        occlusion0 = (occlusion0 > 25) & (occlusion0 < 250);
-    }
+        // Decode camera0
+        std::vector<cv::Mat> frames0Primary(frames0Rect.begin()+2, frames0Rect.begin()+2+nStepsPrimary);
+        std::vector<cv::Mat> frames0Secondary(frames0Rect.begin()+2+nStepsPrimary, frames0Rect.end());
-    // Decode camera0
+        frames0Rect.clear();
-    std::vector<cv::Mat> frames0Primary(frames0Rect.begin()+2, frames0Rect.begin()+2+nStepsPrimary);
-    std::vector<cv::Mat> frames0Secondary(frames0Rect.begin()+2+nStepsPrimary, frames0Rect.end());
     std::vector<cv::Mat> F0Primary = getDFTComponents(frames0Primary);
+    frames0Primary.clear();
     cv::Mat up0Primary;
     cv::phase(F0Primary[2], -F0Primary[3], up0Primary);
     std::vector<cv::Mat> F0Secondary = getDFTComponents(frames0Secondary);
+    frames0Secondary.clear();
     cv::Mat up0Secondary;
     cv::phase(F0Secondary[2], -F0Secondary[3], up0Secondary);
     cv::Mat up0Equivalent = up0Secondary - up0Primary;
     up0Equivalent = cvtools::modulo(up0Equivalent, 2.0*CV_PI);
-    cv::Mat up0 = unwrapWithCue(up0Primary, up0Equivalent, nPeriodsPrimary);
+    up0 = unwrapWithCue(up0Primary, up0Equivalent, nPeriodsPrimary);
     up0 *= screenCols/(2.0*CV_PI);
     // Signal energy at unit frequency
     cv::Mat amplitude0Primary, amplitude0Secondary;
     cv::magnitude(F0Primary[2], -F0Primary[3], amplitude0Primary);
     cv::magnitude(F0Secondary[2], -F0Secondary[3], amplitude0Secondary);
     // Collected signal energy at higher frequencies
     cv::Mat energy0Primary(frameRectRows, frameRectCols, CV_32F, cv::Scalar(0.0));
     for(unsigned int i=0; i<nStepsPrimary-1; i++){
         cv::Mat magnitude;
         cv::magnitude(F0Primary[i*2 + 2], F0Primary[i*2 + 3], magnitude);
         cv::add(energy0Primary, magnitude, energy0Primary, cv::noArray(), CV_32F);
+    }
     cv::Mat energy0Secondary(frameRectRows, frameRectCols, CV_32F, cv::Scalar(0.0));
     for(unsigned int i=0; i<nStepsSecondary-1; i++){
         cv::Mat magnitude;
         cv::magnitude(F0Secondary[i*2 + 2], F0Secondary[i*2 + 3], magnitude);
         cv::add(energy0Secondary, magnitude, energy0Secondary, cv::noArray(), CV_32F);
+    }
+    // Threshold on energy at primary frequency
+    occlusion0 = occlusion0 & (amplitude0 > 5.0*nStepsPrimary);
+    // Threshold on energy ratios
+    occlusion0 = occlusion0 & (amplitude0 > 0.85*energy0Primary);
+    occlusion0 = occlusion0 & (amplitude0 > 0.85*energy0Secondary);
     #ifdef QT_DEBUG
         cvtools::writeMat(up0Primary, "up0Primary.mat", "up0Primary");
         cvtools::writeMat(up0Secondary, "up0Secondary.mat", "up0Secondary");
         cvtools::writeMat(up0Equivalent, "up0Equivalent.mat", "up0Equivalent");
         cvtools::writeMat(up0, "up0.mat", "up0");
         cvtools::writeMat(amplitude0Primary, "amplitude0Primary.mat", "amplitude0Primary");
         cvtools::writeMat(energy0Primary, "energy0Primary.mat", "energy0Primary");
         cvtools::writeMat(energy0Secondary, "energy0Secondary.mat", "energy0Secondary");
     #endif
+}
+    cv::Mat up1;
+    cv::Mat occlusion1;
+    {
+        // Gray-scale and remap
+        std::vector<cv::Mat> frames1Rect(N);
+        for(unsigned int i=0; i<N; i++){
+            cv::Mat temp;
+            cv::cvtColor(frames1[i], temp, CV_BayerBG2GRAY);
+            cv::remap(temp, frames1Rect[i], map1X, map1Y, CV_INTER_LINEAR);
+        }
+        // Occlusion masks
+        cv::subtract(frames1Rect[0], frames1Rect[1], occlusion1);
+        occlusion1 = (occlusion1 > 25) & (occlusion1 < 250);
+        // Decode camera1
+        std::vector<cv::Mat> frames1Primary(frames1Rect.begin()+2, frames1Rect.begin()+2+nStepsPrimary);
+        std::vector<cv::Mat> frames1Secondary(frames1Rect.begin()+2+nStepsPrimary, frames1Rect.end());
-    // Decode camera1
+        frames1Rect.clear();
-    std::vector<cv::Mat> frames1Primary(frames1Rect.begin()+2, frames1Rect.begin()+2+nStepsPrimary);
-    std::vector<cv::Mat> frames1Secondary(frames1Rect.begin()+2+nStepsPrimary, frames1Rect.end());
     std::vector<cv::Mat> F1Primary = getDFTComponents(frames1Primary);
+    frames1Primary.clear();
     cv::Mat up1Primary;
     cv::phase(F1Primary[2], -F1Primary[3], up1Primary);
     std::vector<cv::Mat> F1Secondary = getDFTComponents(frames1Secondary);
+    frames1Secondary.clear();
     cv::Mat up1Secondary;
     cv::phase(F1Secondary[2], -F1Secondary[3], up1Secondary);
     cv::Mat up1Equivalent = up1Secondary - up1Primary;
     up1Equivalent = cvtools::modulo(up1Equivalent, 2.0*CV_PI);
-    cv::Mat up1 = unwrapWithCue(up1Primary, up1Equivalent, nPeriodsPrimary);
+    up1 = unwrapWithCue(up1Primary, up1Equivalent, nPeriodsPrimary);
     up1 *= screenCols/(2.0*CV_PI);
     // Signal energy at unit frequency
     cv::Mat amplitude1Primary, amplitude1Secondary;
     cv::magnitude(F1Primary[2], -F1Primary[3], amplitude1Primary);
     cv::magnitude(F1Secondary[2], -F1Secondary[3], amplitude1Secondary);
     // Collected signal energy at higher frequencies
     cv::Mat energy1Primary(frameRectRows, frameRectCols, CV_32F, cv::Scalar(0.0));
     for(unsigned int i=0; i<nStepsPrimary-1; i++){
         cv::Mat magnitude;
         cv::magnitude(F1Primary[i*2 + 2], F1Primary[i*2 + 3], magnitude);
         cv::add(energy1Primary, magnitude, energy1Primary, cv::noArray(), CV_32F);
+    }
     cv::Mat energy1Secondary(frameRectRows, frameRectCols, CV_32F, cv::Scalar(0.0));
     for(unsigned int i=0; i<nStepsSecondary-1; i++){
         cv::Mat magnitude;
         cv::magnitude(F1Secondary[i*2 + 2], F1Secondary[i*2 + 3], magnitude);
         cv::add(energy1Secondary, magnitude, energy1Secondary, cv::noArray(), CV_32F);
+    }
-    #ifdef QT_DEBUG
-        cvtools::writeMat(up1, "up1.mat", "up1");
-    #endif
-    // color debayer and remap
-    cv::Mat color0, color1;
-    cv::cvtColor(frames0[0], color0, CV_BayerBG2RGB);
-    cv::remap(color0, color0, map0X, map0Y, CV_INTER_LINEAR);
-    cv::cvtColor(frames1[0], color1, CV_BayerBG2RGB);
-    cv::remap(color1, color1, map1X, map1Y, CV_INTER_LINEAR);
-    #ifdef QT_DEBUG
-        cvtools::writeMat(color0, "color0.mat", "color0");
-        cvtools::writeMat(color1, "color1.mat", "color1");
-    #endif
-    // Occlusion masks
-    cv::Mat occlusion0, occlusion1;
-    cv::subtract(frames0Rect[0], frames0Rect[1], occlusion0);
-    occlusion0 = (occlusion0 > 25) & (occlusion0 < 250);
-    cv::subtract(frames1Rect[0], frames1Rect[1], occlusion1);
-    occlusion1 = (occlusion1 > 25) & (occlusion1 < 250);
     // Threshold on energy at primary frequency
-    occlusion0 = occlusion0 & (amplitude0Primary > 5.0*nStepsPrimary);
-    occlusion1 = occlusion1 & (amplitude1Primary > 5.0*nStepsPrimary);
+    occlusion1 = occlusion1 & (amplitude1 > 5.0*nStepsPrimary);
     // Threshold on energy ratios
-    occlusion0 = occlusion0 & (amplitude0Primary > 0.85*energy0Primary);
+    occlusion1 = occlusion1 & (amplitude1 > 0.85*energy1Primary);
-    occlusion0 = occlusion0 & (amplitude0Secondary > 0.85*energy0Secondary);
     occlusion1 = occlusion1 & (amplitude1Primary > 0.85*energy1Primary);
     occlusion1 = occlusion1 & (amplitude1Secondary > 0.85*energy1Secondary);
+    #ifdef QT_DEBUG
+        cvtools::writeMat(up1, "up1.mat", "up1");
+    #endif
+}
 //    // Erode occlusion masks
 //    cv::Mat strel = cv::getStructuringElement(cv::MORPH_ELLIPSE, cv::Size(5,5));
 //    cv::erode(occlusion0, occlusion0, strel);
 //    cv::erode(occlusion1, occlusion1, strel);
+{
     // Threshold on gradient of phase
     cv::Mat edges0;
     cv::Sobel(up0, edges0, -1, 1, 1, 5);
     occlusion0 = occlusion0 & (abs(edges0) < 10);
     cv::Mat edges1;
     cv::Sobel(up1, edges1, -1, 1, 1, 5);
     occlusion1 = occlusion1 & (abs(edges1) < 10);
     #ifdef QT_DEBUG
         cvtools::writeMat(edges0, "edges0.mat", "edges0");
         cvtools::writeMat(edges1, "edges1.mat", "edges1");
         cvtools::writeMat(occlusion0, "occlusion0.mat", "occlusion0");
         cvtools::writeMat(occlusion1, "occlusion1.mat", "occlusion1");
     #endif
+}
     // Match phase maps
     // camera0 against camera1
     std::vector<cv::Vec2f> q0, q1;
     for(int row=0; row<frameRectRows; row++){
         for(int col=0; col<frameRectCols; col++){
             if(!occlusion0.at<char>(row,col))
                 continue;
             float up0i = up0.at<float>(row,col);
             for(int col1=0; col1<up1.cols-1; col1++){
                 if(!occlusion1.at<char>(row,col1) || !occlusion1.at<char>(row,col1+1))
                     continue;
                 float up1Left = up1.at<float>(row,col1);
                 float up1Right = up1.at<float>(row,col1+1);
                 if((up1Left <= up0i) && (up0i <= up1Right) && (up0i-up1Left < 1.0) && (up1Right-up0i < 1.0) && (up1Right-up1Left > 0.1)){
                     float col1i = col1 + (up0i-up1Left)/(up1Right-up1Left);
                     q0.push_back(cv::Point2f(col, row));
                     q1.push_back(cv::Point2f(col1i, row));
                     break;
+                }
+            }
+        }
+    }
     int nMatches = q0.size();
     if(nMatches < 1){
         Q.resize(0);
         color.resize(0);
         return;
+    }
+{
+    // color debayer and remap
+    cv::Mat color0, color1;
+    cv::cvtColor(frames0[0], color0, CV_BayerBG2RGB);
+    cv::remap(color0, color0, map0X, map0Y, CV_INTER_LINEAR);
+    cv::cvtColor(frames1[0], color1, CV_BayerBG2RGB);
+    cv::remap(color1, color1, map1X, map1Y, CV_INTER_LINEAR);
+    #ifdef QT_DEBUG
+        cvtools::writeMat(color0, "color0.mat", "color0");
+        cvtools::writeMat(color1, "color1.mat", "color1");
+    #endif
-    // Retrieve color information
+        // Retrieve color information
     color.resize(nMatches);
     for(int i=0; i<nMatches; i++){
         cv::Vec3b c0 = color0.at<cv::Vec3b>(q0[i][1], q0[i][0]);
         cv::Vec3b c1 = color1.at<cv::Vec3b>(q1[i][1], q1[i][0]);
         color[i] = 0.5*c0 + 0.5*c1;
+    }
+}
     // Triangulate points
     cv::Mat QMatHomogenous, QMat;
     cv::triangulatePoints(P0, P1, q0, q1, QMatHomogenous);
     cvtools::convertMatFromHomogeneous(QMatHomogenous, QMat);
     // Undo rectification
     cv::Mat R0Inv;
     cv::Mat(R0.t()).convertTo(R0Inv, CV_32F);
     QMat = R0Inv*QMat;
     cvtools::matToPoints3f(QMat, Q);
+}

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(root)/src/algorithm/AlgorithmPhaseShiftTwoFreq.cpp – Rev 200 → 207