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Region.cc Go to the documentation of this file. //-*-c++-*- #include <cmath> #include <vector> #include <list> #include "Measures.h" #include "SketchSpace.h" #include "SketchIndices.h" #include "Sketch.h" #include "Region.h" namespace DualCoding { // be careful about changing this value, b/c memset writes bytes #define NOTCOMPUTED 0 Region::Region(const SketchSpace& _space) : SketchIndices(), space(_space), topBound(NOTCOMPUTED), botBound(NOTCOMPUTED), leftBound(NOTCOMPUTED), rightBound(NOTCOMPUTED), area(NOTCOMPUTED) { memset(&moments, NOTCOMPUTED, sizeof(float)*(MAX_MOMENT+1)*(MAX_MOMENT+1)); memset(&cmoments, NOTCOMPUTED, sizeof(float)*(MAX_MOMENT+1)*(MAX_MOMENT+1)); } void Region::recomputeProperties() { topBound = NOTCOMPUTED; botBound = NOTCOMPUTED; leftBound = NOTCOMPUTED; rightBound = NOTCOMPUTED; area = NOTCOMPUTED; memset(&moments, NOTCOMPUTED, sizeof(float)*(MAX_MOMENT+1)*(MAX_MOMENT+1)); memset(&cmoments, NOTCOMPUTED, sizeof(float)*(MAX_MOMENT+1)*(MAX_MOMENT+1)); } std::list<Region> Region::extractRegions(const Sketch<usint>& labels, int area_thresh) { size_t length = labels->getNumPixels(); // tally up areas vector<int> areas(labels->max()+1, 0); // not having +1 may have caused malloc crash for (size_t i = 0; i < length; i++) if (labels[i] != 0) areas[labels[i]]++; // add unsorted Regions to list std::list<Region> regionlist; for (int r = 0; r < (int)(areas.size()); r++) { if (areas[r] >= area_thresh) { // construct Region and add to list Region cur_reg(labels->getSpace()); for (size_t i = 0; i < length; i++) if (labels[i] == r) cur_reg.table.insert(i); cur_reg.area = areas[r]; // go ahead and pre-set area regionlist.push_back(cur_reg); // actually calls copy constructor } } regionlist.sort(); return regionlist; } Region Region::extractRegion(const Sketch<bool>& sketch) { size_t length = sketch->getNumPixels(); Region cur_reg(sketch->getSpace()); int area = 0; for (size_t i = 0; i< length; i++) { if (sketch[i]) { area++; cur_reg.table.insert(i); } } cur_reg.area = area; return cur_reg; } bool Region::operator< (const Region& other) const { return (area > other.area); } int Region::findTopBound() { if (topBound != NOTCOMPUTED) // problem if NOTCOMPUTED == 0 return topBound; else { SketchIndices::CI it; int top = 9999; int temp = 0; int width = space.getWidth(); //int width = space.getWidth()+1; for (it = table.begin(); it != table.end(); it++) if ((*it)/width < top) { top = (*it)/width; temp = *it; } // cout << "Top bound: " << temp << " / " << width << " = " << top << endl; topBound = top; return top; } } int Region::findBotBound() { if (botBound != NOTCOMPUTED) // problem if NOTCOMPUTED == 0 return botBound; else { SketchIndices::CI it; int bot = -1; int width = space.getWidth(); //int width = space.getWidth()+1; for (it = table.begin(); it != table.end(); it++) if ((*it+1)/width > bot) bot = (*it)/width; botBound = bot; return bot; } } int Region::findLeftBound() { if (leftBound != NOTCOMPUTED) // problem if NOTCOMPUTED == 0 return leftBound; else { SketchIndices::CI it; int left = 9999; int width = space.getWidth(); for (it = table.begin(); it != table.end(); it++) if ((*it)%width < left) left = (*it)%width; leftBound = left; return left; } } int Region::findRightBound() { if (rightBound != NOTCOMPUTED) // problem if NOTCOMPUTED == 0 return rightBound; else { SketchIndices::CI it; int right = -1; int width = space.getWidth(); for (it = table.begin(); it != table.end(); it++) if ((*it)%width > right) right = (*it)%width; rightBound = right; return right; } } // returns x coordinate of first match Point for given y_coord int Region::findXcoordFor(const coordinate_t y_coord) { const int width = space.getWidth(); // const int width = space.getWidth()+1; for (SketchIndices::CI it = table.begin(); it != table.end(); it++) if ((*it)/width == y_coord) return (*it)%width; //return (*it)%(width-1); return -1; } // returns y coordinate of first match Point for given x_coord int Region::findYcoordFor(const coordinate_t x_coord) { const int width = space.getWidth(); for (SketchIndices::CI it = table.begin(); it != table.end(); it++) if ((*it)%width == x_coord) return (*it)/width; return -1; } Point Region::findTopBoundPoint() { const coordinate_t y_coord = findTopBound(); return Point(findXcoordFor(y_coord),y_coord); } Point Region::findBotBoundPoint() { const coordinate_t y_coord = findBotBound(); return Point(findXcoordFor(y_coord),y_coord); } Point Region::findLeftBoundPoint() { const coordinate_t x_coord = findLeftBound(); return Point(x_coord, findYcoordFor(x_coord)); } Point Region::findRightBoundPoint() { const coordinate_t x_coord = findRightBound(); return Point(x_coord, findYcoordFor(x_coord)); } bool Region::isContained(const Point& pt, const int max_dist) { const int x_coord = (int) pt.coordX(); const int y_coord = (int) pt.coordY(); const int width = space.getWidth(); // cout << pt << endl; for (SketchIndices::CI it = table.begin(); it != table.end(); it++) if (((*it)%width <= x_coord+max_dist && (*it)%width >= x_coord-max_dist) && ((*it)/width <= y_coord+max_dist && (*it)/width >= y_coord-max_dist)) return true; return false; } Point Region::mostDistantPtFrom(const LineData& ln) { float max_dist = 0; Point most_dist_pt; const int width = space.getWidth(); // cout << pt << endl; for (SketchIndices::CI it = table.begin(); it != table.end(); it++) { if (ln.perpendicularDistanceFrom(Point((*it)%width, (*it)/width)) > max_dist) { max_dist = ln.perpendicularDistanceFrom(Point((*it)%width, (*it)/width)); most_dist_pt.setCoords((*it)%width, (*it)/width); } } return most_dist_pt; } // All moment-based equations taken from Prokop & Reeves 1992, "A survey of moment-based techniques for unoccluded object representation and recognition" float Region::findMoment(size_t p, size_t q) { // should add in more efficient routines for some low-moments like area if(moments[p][q] != NOTCOMPUTED) { return moments[p][q]; } else { // should pre-calculate powers for rows and columns, as in Flusser (1998) int xmin = findLeftBound(), xmax = findRightBound(); float powp[xmax-xmin+1]; for (int x = xmin; x <= xmax; x++) { if (x == 0) // if don't check for this, risk floating-point exception powp[x-xmin] = 1; else powp[x-xmin] = pow((float)(x), (float)p); } int ymin = findTopBound(), ymax = findBotBound(); float powq[ymax-ymin+1]; for (int y = ymin; y <= ymax; y++) { if (y == 0) powq[y-ymin] = 1; else powq[y-ymin] = pow((float)(y), (float)q); } float m = 0; int xval, yval; for (SketchIndices::CI it = table.begin(); it != table.end(); ++it) { xval = (*it) % space.getWidth(); yval = (*it) / space.getWidth(); m += powp[xval-xmin] * powq[yval-ymin]; } moments[p][q] = m; return m; } } float Region::findCentralMoment(size_t p, size_t q) { // should add in more efficient routines for some low-moments like area if(cmoments[p][q] != NOTCOMPUTED) { return cmoments[p][q]; } else { Point centroid = findCentroid(); //cen.first; const float cx = centroid.coordX(); const float cy = centroid.coordY(); // should pre-calculate powers for rows and columns, as in Flusser (1998) int xmin = findLeftBound(), xmax = findRightBound(); float powp[xmax-xmin+1]; for (int x = xmin; x <= xmax; x++) { if ((x-cx)==0) // if don't check for this, risk floating-point exception powp[x-xmin] = 1; else powp[x-xmin] = pow((float)(x-cx), (float)p); } int ymin = findTopBound(), ymax = findBotBound(); float powq[ymax-ymin+1]; for (int y = ymin; y <= ymax; y++) { if ((y-cy)==0) powq[y-ymin] = 1; else powq[y-ymin] = pow((float)(y-cy), (float)q); } float m = 0; int xval, yval; for (SketchIndices::CI it = table.begin(); it != table.end(); ++it) { xval = (*it) % space.getWidth(); yval = (*it) / space.getWidth(); //m += pow(xval,(float)p) * pow(yval,(float)q); m += powp[xval-xmin] * powq[yval-ymin]; } cmoments[p][q] = m; return m; } } float Region::findNormCentralMoment(size_t p, size_t q) { // normalize // from Gonzalez & Woods (1992) float gamma = (p+q)/2 + 1; return(findCentralMoment(p,q) / pow(findArea(), gamma)); } int Region::findArea() { if (area != NOTCOMPUTED) return area; else { area = table.size(); return area; } } Point Region::findCentroid() { findArea(); return Point(findMoment(1,0)/area, findMoment(0,1)/area); // centroid.first = findMoment(1,0)/findMoment(0,0); // centroid.second = findMoment(0,1)/findMoment(0,0); // return centroid; /* if (centroid.first != NOTCOMPUTED) { return centroid; } else { int xsum = 0, ysum = 0; typedef SketchIndices::const_iterator CI; for (CI i = begin(); i != end(); ++i) { xsum += (*i) % space.getWidth(); ysum += (*i) / space.getWidth(); } centroid.first = xsum/findArea(); centroid.second = ysum/findArea(); return centroid; }*/ } AngPi Region::findPrincipalAxisOrientation() { return AngPi((0.5)*atan2(2*findCentralMoment(1,1), findCentralMoment(2,0)-findCentralMoment(0,2))); } float Region::findSemiMajorAxisLength() { float u20 = findCentralMoment(2,0); float u02 = findCentralMoment(0,2); float u11 = findCentralMoment(1,1); // float u00 = findCentralMoment(0,0); float u00 = findArea(); return sqrt((2.0*(u20+u02+sqrt((u20-u02)*(u20-u02)+4*u11*u11)))/u00); } float Region::findSemiMinorAxisLength() { float u20 = findCentralMoment(2,0); float u02 = findCentralMoment(0,2); float u11 = findCentralMoment(1,1); // float u00 = findCentralMoment(0,0); float u00 = findArea(); return sqrt((2.0*(u20+u02-sqrt((u20-u02)*(u20-u02)+4*u11*u11)))/u00); } /* FIX THIS float Region::findRadius() { float u20 = findCentralMoment(2,0); float u02 = findCentralMoment(0,2); float u00 = findArea(); return sqrt((2.0*(u20+u02))/u00); } */ } // namespace

DualCoding 3.0beta

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