correction des bugs de compilation et première implémentation de la fft

This commit is contained in:
Guillaume Courrier 2019-11-26 13:24:33 +01:00
parent 26dc3f7b3a
commit a600e8e91e
4 changed files with 51 additions and 107 deletions

View file

@ -1,51 +1,13 @@
#include <fftw3.h>
#include <math.hpp>
#include <cmath>
#include <libplotcpp/plotcpp.hpp>
double pi() {
return 3.1415;
}
std::vector<double> tfd2vect(fftw_complex* tfd, int N) {
std::vector<double> res;
auto it = tfd;
for (int i = 0; i != N; ++i) {
fftw_complex c = {*it[0], *it[1]};
res.push_back(sqrt(c[0]*c[0] + c[1]*c[1]));
it++;
}
return res;
}
int main(int argc, char** argv) {
QApplication app(argc, argv);
fftw_complex *in, *out;
fftw_plan p;
math::csignal s;
int N = 500;
in = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * N);
out = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * N);
p = fftw_plan_dft_1d(N, in, out, FFTW_FORWARD, FFTW_MEASURE);
std::vector<double> xx;
for (int i = 0; i != N; ++i) {
xx.push_back(i);
for (int i=0; i<100; ++i) {
s.push_back(std::sin(2*math::pi()*50*i/100));
}
math::csignal tfd = math::fft(s);
for (int i = 0; i != N; ++i) {
in[i][0] = sin(2*pi()*50*i/N);
}
fftw_execute(p); /* repeat as needed */
std::vector<double> res = tfd2vect(out, N);
PlotCpp g;
g.plot(xx, res);
g.draw();
fftw_destroy_plan(p);
fftw_free(in); fftw_free(out);
return app.exec();
return 0;
}

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@ -1,11 +1,8 @@
# file(GLOB headers *.hpp)
# file(GLOB lib_files *.cpp)
# add_executable(traitement traitement.cpp)
# target_link_libraries(traitement ${OpenCV_LIBS} fftw3)
add_executable(test-fft test-fft.cpp)
target_link_libraries(test-fft)
add_executable(traitement traitement.cpp)
target_link_libraries(traitement ${OpenCV_LIBS} fftw3)
# target_include_directories(blk PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
# target_compile_options (blk PUBLIC -std=c++11 )

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@ -8,28 +8,42 @@
namespace math {
using complex = std::complex<float>;
using complex = std::complex<double>;
using signal = std::vector<double>;
using csignal = std::vector<complex>;
using contour = std::vector<cv::Point>;
constexpr double pi() {return std::atan(1)*4;}
//TODO implémenter la fft
csignal fft(const signal& input) {
//TODO: s'assurer que le signal est bien formé (i.e. bonne taille)
return fft_rec(input);
csignal cont2sig(const contour& cont) {
csignal sig;
auto sig_it = sig.begin();
auto cont_it = cont.begin();
for (auto cont_it = cont.begin(); cont_it != cont.end(); ++cont_it) {
*(sig_it++) = complex((*cont_it).x, (*cont_it).y);
}
return sig;
};
csignal fft_rec(const signal& input) {
complex mean(const csignal& sig) {
complex res = 0;
for (auto x: sig) {
res += x;
}
return complex(res.real()/sig.size(), res.imag()/sig.size());
};
//TODO implémenter la fft
csignal fft_rec(const csignal& input) {
int size = input.size();
if (size == 1) {
return input;
return csignal();
} else {
signal odd;
signal even;
std::back_insert_iterator<signal> odd_back_it(odd);
std::back_insert_iterator<signal> even_back_it(even);
csignal odd;
csignal even;
std::back_insert_iterator<csignal> odd_back_it(odd);
std::back_insert_iterator<csignal> even_back_it(even);
bool insert_in_even = false;
for (auto it = input.begin(); it != input.end(); ++it) {
@ -42,9 +56,9 @@ namespace math {
}
}
signal odd_fft = fft_rec(odd);
signal even_fft = fft_rec(even);
signal res;
csignal odd_fft = fft_rec(odd);
csignal even_fft = fft_rec(even);
csignal res;
res.reserve(size);
for (int k = 0; k<size/2; ++k) {
@ -56,38 +70,31 @@ namespace math {
}
}
complex mean(const signal& sig) {
complex res = 0;
for (auto x: sig) {
res += x;
}
return complex(res.real()/sig.size(), res.imag()/sig.size());
csignal fft(const csignal& input) {
//TODO: s'assurer que le signal est bien formé (i.e. bonne taille)
return fft_rec(input);
};
signal cont2sig(const contour& cont) {
signal sig;
auto sig_it = sig.begin();
auto cont_it = cont.begin();
for (auto cont_it = cont.begin(); cont_it != cont.end(); ++cont_it) {
*sig_it = complex((*cont_it).x, (*cont_it).y);
sig_it++;
}
return sig;
};
contour coef2cont(const signal& tfd, complex mean, int size, int cmax) {
contour coef2cont(const csignal& tfd, complex mean, int size, int cmax) {
contour cont;
auto tf_it = tfd.begin();
auto cont_it = cont.begin();
for (auto tf_it = tfd.begin(); tf_it != tfd.end(); ++tf_it) {
//TODO retrouver la formule
//*cont_it = mean;
//*cont_it = mean + ...;
}
return cont;
};
contour simplify_contour(const contour& cont, int cmax) {
contour res;
csignal z = cont2sig(cont);
complex zm = mean(z);
csignal tfd = fft(z);
return coef2cont(tfd, zm, 0, cmax);
};
int max_cont(const std::vector<contour>& contours) {
int max = 0;
int id = 0;
@ -99,13 +106,4 @@ namespace math {
}
return id;
};
contour simplify_contour(const contour& cont, int cmax) {
contour res;
signal z = cont2sig(cont);
complex zm = mean(z);
signal tfd = fft(z);
res = coef2cont(tfd, zm, 0, cmax);
return res;
};
}

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@ -1,13 +0,0 @@
#include <math.hpp>
#include <cmath>
int main(int argc, char** argv) {
math::signal s;
for (int i=0; i<100; ++i) {
s.push_back(std::sin(2*math::pi()*50*i/100));
}
math::fft(s);
return 0;
}