string optFilterMethodName = SignalFilter::FILTER_METHOD_CONVOLUTION_STR;
string optInterpName = Backprojector::INTERP_LINEAR_STR;
string optBackprojName = Backprojector::BPROJ_IDIFF2_STR;
string optFilterMethodName = SignalFilter::FILTER_METHOD_CONVOLUTION_STR;
string optInterpName = Backprojector::INTERP_LINEAR_STR;
string optBackprojName = Backprojector::BPROJ_IDIFF2_STR;