c@391: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
c@391: 
c@391: #include "maths/MedianFilter.h"
c@391: 
c@391: #include <cmath>
c@407: #include <cstdlib>
c@391: 
c@391: #define BOOST_TEST_DYN_LINK
c@391: #define BOOST_TEST_MAIN
c@391: 
c@391: #include <boost/test/unit_test.hpp>
c@391: 
c@391: BOOST_AUTO_TEST_SUITE(TestMedianFilter)
c@391: 
c@391: BOOST_AUTO_TEST_CASE(odd)
c@391: {
c@391:     // A median filter of size N always retains a pool of N elements,
c@391:     // which start out all-zero. So the output median will remain zero
c@391:     // until N/2 elements have been pushed.
c@391:     MedianFilter<double> f(3);
cannam@476:     f.push(1);                  // 0 0 1
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(-3);                 // 0 1 -3
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(5);                  // 1 -3 5
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
cannam@476:     f.push(7);                  // -3 5 7
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // 5 7 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // 7 3 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 3);
c@391: }
c@391: 
c@391: BOOST_AUTO_TEST_CASE(even)
c@391: {
c@391:     // Our median does not halve the difference (should it??), it just
c@391:     // returns the next element from the input set
c@391:     MedianFilter<double> f(4);
cannam@476:     f.push(1);                  // 0 0 0 1
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(-3);                 // 0 0 1 -3
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(5);                  // 0 1 -3 5
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
cannam@476:     f.push(7);                  // 1 -3 5 7
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // -3 5 7 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // 5 7 3 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
c@391: }
c@391: 
c@391: BOOST_AUTO_TEST_CASE(odd75)
c@391: {
c@391:     MedianFilter<double> f(5, 75.f);
cannam@476:     f.push(1);                  // 0 0 0 0 1
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(-3);                 // 0 0 0 1 -3
c@391:     BOOST_CHECK_EQUAL(f.get(), 0);
cannam@476:     f.push(5);                  // 0 0 1 -3 5
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
cannam@476:     f.push(7);                  // 0 1 -3 5 7
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // 0 -3 5 7 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(3);                  // 0 5 7 3 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
c@391: }
c@391: 
c@391: BOOST_AUTO_TEST_CASE(even75)
c@391: {
c@391:     MedianFilter<double> f(4, 75.f);
cannam@476:     f.push(1);                  // 0 0 0 1
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
cannam@476:     f.push(-3);                 // 0 0 1 -3
c@391:     BOOST_CHECK_EQUAL(f.get(), 1);
cannam@476:     f.push(5);                  // 0 1 -3 5
c@391:     BOOST_CHECK_EQUAL(f.get(), 5);
cannam@476:     f.push(7);                  // 1 -3 5 7
c@391:     BOOST_CHECK_EQUAL(f.get(), 7);
c@391:     BOOST_CHECK_EQUAL(f.get(), 7);
cannam@476:     f.push(3);                  // -3 5 7 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 7);
cannam@476:     f.push(3);                  // 5 7 3 3
c@391:     BOOST_CHECK_EQUAL(f.get(), 7);
c@391: }
c@391: 
c@392: BOOST_AUTO_TEST_CASE(oddStandalone)
c@392: {
c@392:     // The standalone (static filter() method) function is intended to
c@392:     // match e.g. MATLAB median filter, filtering a row at once
c@392:     // assuming the values beyond its edges are zeroes. This basically
c@392:     // just means it needs to compensate for the latency in the raw
c@392:     // filter:
c@392:     //
c@392:     // Raw filter
c@392:     //    1 3 5 7   ->   0 1 3 5    (N=3)
c@392:     // (because at each step only the values up to that step are
c@392:     // available)
c@392:     //
c@392:     // Standalone function:
c@392:     //    1 3 5 7   ->   1 3 5 5    (N=3)
c@392:     
c@392:     std::vector<double> in;
c@392:     in.push_back(1);
c@392:     in.push_back(3);
c@392:     in.push_back(5);
c@392:     in.push_back(7);
c@392: 
c@392:     std::vector<double> out = MedianFilter<double>::filter(3, in);
c@392:     BOOST_CHECK_EQUAL(out[0], 1);
c@392:     BOOST_CHECK_EQUAL(out[1], 3);
c@392:     BOOST_CHECK_EQUAL(out[2], 5);
c@392:     BOOST_CHECK_EQUAL(out[3], 5);
c@392: }
c@392: 
c@392: BOOST_AUTO_TEST_CASE(evenStandalone)
c@392: {
c@392:     // See above. But note that the even length does not match the
c@392:     // MATLAB because it doesn't halve the middle, as MATLAB does
c@392: 
c@392:     std::vector<double> in;
c@392:     in.push_back(1);
c@392:     in.push_back(3);
c@392:     in.push_back(5);
c@392:     in.push_back(7);
c@392: 
c@392:     std::vector<double> out = MedianFilter<double>::filter(4, in);
c@392:     BOOST_CHECK_EQUAL(out[0], 3);
c@392:     BOOST_CHECK_EQUAL(out[1], 5);
c@392:     BOOST_CHECK_EQUAL(out[2], 5);
c@392:     BOOST_CHECK_EQUAL(out[3], 5);
c@392: }
c@392: 
c@392: BOOST_AUTO_TEST_CASE(standaloneEmpty)
c@392: {
c@392:     std::vector<double> in;
c@392:     std::vector<double> out1 = MedianFilter<double>::filter(3, in);
c@392:     BOOST_CHECK_EQUAL(out1.size(), 0);
c@392:     std::vector<double> out2 = MedianFilter<double>::filter(4, in);
c@392:     BOOST_CHECK_EQUAL(out2.size(), 0);
c@392: }
c@392: 
c@392: BOOST_AUTO_TEST_CASE(types)
c@392: {
c@392:     MedianFilter<double> dfilt(3);
c@392:     dfilt.push(1.2);
c@392:     BOOST_CHECK_EQUAL(dfilt.get(), 0.0);
c@392:     dfilt.push(2.4);
c@392:     BOOST_CHECK_EQUAL(dfilt.get(), 1.2);
c@392:     dfilt.push(1e-6);
c@392:     BOOST_CHECK_EQUAL(dfilt.get(), 1.2);
c@392:     dfilt.push(1e6);
c@392:     BOOST_CHECK_EQUAL(dfilt.get(), 2.4);
c@392: 
c@392:     MedianFilter<int> ifilt(3);
c@392:     ifilt.push(1);
c@392:     BOOST_CHECK_EQUAL(ifilt.get(), 0);
c@392:     ifilt.push(2);
c@392:     BOOST_CHECK_EQUAL(ifilt.get(), 1);
c@392:     ifilt.push(0);
c@392:     BOOST_CHECK_EQUAL(ifilt.get(), 1);
c@392:     ifilt.push(1000);
c@392:     BOOST_CHECK_EQUAL(ifilt.get(), 2);
c@392: }
c@392: 
c@407: BOOST_AUTO_TEST_CASE(inf)
c@407: {
c@407:     // Inf and -Inf should behave normally
c@407:     double pinf = strtod("Inf", 0);
c@407:     double ninf = strtod("-Inf", 0);
c@407:     MedianFilter<double> dfilt(3);
c@407:     dfilt.push(1.0);
c@407:     dfilt.push(2.0);
c@407:     dfilt.push(pinf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 2.0);
c@407:     dfilt.push(pinf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), pinf);
c@407:     dfilt.push(pinf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), pinf);
c@407:     dfilt.push(2.0);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), pinf);
c@407:     dfilt.push(1.0);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 2.0);
c@407:     dfilt.push(ninf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 1.0);
c@407:     dfilt.push(pinf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 1.0);
c@407:     dfilt.push(ninf);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), ninf);
c@407: }
c@407: 
c@407: BOOST_AUTO_TEST_CASE(nan)
c@407: {
c@407:     // The filter should never accept a NaN, because it breaks sorting
c@407:     // and comparison and that will break the filter. Instead it
c@407:     // should insert 0.
c@407:     double nan = strtod("NaN", 0);
c@407:     MedianFilter<double> dfilt(3);
c@407:     dfilt.push(1.0);
c@407:     dfilt.push(2.0);
c@407:     dfilt.push(nan);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 1.0);
c@407:     dfilt.push(nan);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 0.0);
c@407:     dfilt.push(-11.0);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), 0.0);
c@407:     dfilt.push(-1.0);
c@407:     BOOST_CHECK_EQUAL(dfilt.get(), -1.0);
c@407: }
c@407: 
c@391: BOOST_AUTO_TEST_SUITE_END()
c@391: 
c@391: