+// REFERENCES
+// G.T. Herman, Image Reconstruction From Projections, 1980
+
+bool
+ImageFile::comparativeStatistics (const ImageFile& imComp, double& d, double& r, double& e) const
+{
+ if (imComp.nx() != m_nx && imComp.ny() != m_ny) {
+ sys_error (ERR_WARNING, "Image sizes differ [ImageFile::comparativeStatistics]");
+ return false;
+ }
+ ImageFileArrayConst v = getArray();
+ if (v == NULL || m_nx == 0 || m_ny == 0)
+ return false;
+
+ ImageFileArrayConst vComp = imComp.getArray();
+
+ double myMean = 0.;
+ for (unsigned int ix = 0; ix < m_nx; ix++) {
+ for (unsigned int iy = 0; iy < m_ny; iy++) {
+ myMean += v[ix][iy];
+ }
+ }
+ myMean /= (m_nx * m_ny);
+
+ double sqErrorSum = 0.;
+ double absErrorSum = 0.;
+ double sqDiffFromMeanSum = 0.;
+ double absValueSum = 0.;
+ for (unsigned int ix2 = 0; ix2 < m_nx; ix2++) {
+ for (unsigned int iy = 0; iy < m_ny; iy++) {
+ double diff = v[ix2][iy] - vComp[ix2][iy];
+ sqErrorSum += diff * diff;
+ absErrorSum += fabs(diff);
+ double diffFromMean = v[ix2][iy] - myMean;
+ sqDiffFromMeanSum += diffFromMean * diffFromMean;
+ absValueSum += fabs(v[ix2][iy]);
+ }
+ }
+
+ d = ::sqrt (sqErrorSum / sqDiffFromMeanSum);
+ r = absErrorSum / absValueSum;
+
+ int hx = m_nx / 2;
+ int hy = m_ny / 2;
+ double eMax = -1;
+ for (int ix3 = 0; ix3 < hx; ix3++) {
+ for (int iy = 0; iy < hy; iy++) {
+ double avgPixel = 0.25 * (v[2*ix3][2*iy] + v[2*ix3+1][2*iy] + v[2*ix3][2*iy+1] + v[2*ix3+1][2*iy+1]);
+ double avgPixelComp = 0.25 * (vComp[2*ix3][2*iy] + vComp[2*ix3+1][2*iy] + vComp[2*ix3][2*iy+1] + vComp[2*ix3+1][2*iy+1]);
+ double error = fabs (avgPixel - avgPixelComp);
+ if (error > eMax)
+ eMax = error;
+ }
+ }
+
+ e = eMax;
+
+ return true;
+}
+
+
+bool
+ImageFile::printComparativeStatistics (const ImageFile& imComp, std::ostream& os) const
+{
+ double d, r, e;
+
+ if (comparativeStatistics (imComp, d, r, e)) {
+ os << " Normalized root mean squared distance (d): " << d << std::endl;
+ os << " Normalized mean absolute distance (r): " << r << std::endl;
+ os << "Worst case distance (2x2 pixel average) (e): " << e << std::endl;
+ return true;
+ }
+ return false;
+}
+
+
+void
+ImageFile::printStatistics (std::ostream& os) const
+{
+ double min, max, mean, mode, median, stddev;
+
+ statistics (min, max, mean, mode, median, stddev);
+ if (isComplex())
+ os << "Real Component Statistics" << std::endl;
+
+ os << " min: " << min << std::endl;
+ os << " max: " << max << std::endl;
+ os << " mean: " << mean << std::endl;
+ os << " mode: " << mode << std::endl;
+ os << "median: " << median << std::endl;
+ os << "stddev: " << stddev << std::endl;
+
+ if (isComplex()) {
+ statistics (getImaginaryArray(), min, max, mean, mode, median, stddev);
+ os << std::endl << "Imaginary Component Statistics" << std::endl;
+ os << " min: " << min << std::endl;
+ os << " max: " << max << std::endl;
+ os << " mean: " << mean << std::endl;
+ os << " mode: " << mode << std::endl;
+ os << "median: " << median << std::endl;
+ os << "stddev: " << stddev << std::endl;
+ }
+}
+
+
+void
+ImageFile::statistics (double& min, double& max, double& mean, double& mode, double& median, double& stddev) const
+{
+ ImageFileArrayConst v = getArray();
+ statistics (v, min, max, mean, mode, median, stddev);
+}
+
+
+void
+ImageFile::statistics (ImageFileArrayConst v, double& min, double& max, double& mean, double& mode, double& median, double& stddev) const
+{
+ int nx = m_nx;
+ int ny = m_ny;
+
+ if (v == NULL || nx == 0 || ny == 0)
+ return;
+
+ std::vector<double> vecImage;
+ int iVec = 0;
+ vecImage.resize (nx * ny);
+ for (int ix = 0; ix < nx; ix++) {
+ for (int iy = 0; iy < ny; iy++)
+ vecImage[iVec++] = v[ix][iy];
+ }
+
+ vectorNumericStatistics (vecImage, nx * ny, min, max, mean, mode, median, stddev);
+}