attempt to improve FFT zoom resolution

This commit is contained in:
Charles J. Cliffe 2015-01-30 19:31:32 -05:00
parent f87ee8dc6f
commit fb5a7e5b8f
2 changed files with 103 additions and 65 deletions

View File

@ -36,7 +36,7 @@ wxEND_EVENT_TABLE()
WaterfallCanvas::WaterfallCanvas(wxWindow *parent, int *attribList) :
InteractiveCanvas(parent, attribList), spectrumCanvas(NULL), dragState(WF_DRAG_NONE), nextDragState(WF_DRAG_NONE), fft_size(0), waterfall_lines(
0), plan(
NULL), in(NULL), out(NULL), resampler(NULL), resamplerRatio(0), lastInputBandwidth(0), zoom(1), mouseZoom(1), otherWaterfallCanvas(NULL), polling(true) {
NULL), in(NULL), out(NULL), resampler(NULL), resamplerRatio(0), lastInputBandwidth(0), zoom(1), mouseZoom(1), otherWaterfallCanvas(NULL), polling(true), last_data_size(0), fft_in_data(NULL), fft_last_data(NULL) {
glContext = new WaterfallContext(this, &wxGetApp().GetContext(this));
@ -64,6 +64,14 @@ void WaterfallCanvas::setup(int fft_size_in, int waterfall_lines_in) {
free(in);
}
in = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fft_size);
if (fft_in_data) {
free(fft_in_data);
}
fft_in_data = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fft_size);
if (fft_last_data) {
free(fft_last_data);
}
fft_last_data = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fft_size);
if (out) {
free(out);
}
@ -394,6 +402,8 @@ void WaterfallCanvas::setData(DemodulatorThreadIQData *input) {
spectrum_points.resize(fft_size * 2);
}
unsigned int num_written;
if (isView) {
if (!input->frequency || !input->sampleRate) {
return;
@ -447,104 +457,129 @@ void WaterfallCanvas::setData(DemodulatorThreadIQData *input) {
resampleBuffer.resize(out_size);
}
unsigned int num_written;
msresamp_crcf_execute(resampler, &shiftBuffer[0], input->data.size(), &resampleBuffer[0], &num_written);
resampleBuffer.resize(fft_size);
if (num_written < fft_size) {
for (int i = 0; i < num_written; i++) {
in[i][0] = resampleBuffer[i].real;
in[i][1] = resampleBuffer[i].imag;
fft_in_data[i][0] = resampleBuffer[i].real;
fft_in_data[i][1] = resampleBuffer[i].imag;
}
for (int i = num_written; i < fft_size; i++) {
in[i][0] = 0;
in[i][1] = 0;
fft_in_data[i][0] = 0;
fft_in_data[i][1] = 0;
}
} else {
for (int i = 0; i < fft_size; i++) {
in[i][0] = resampleBuffer[i].real;
in[i][1] = resampleBuffer[i].imag;
fft_in_data[i][0] = resampleBuffer[i].real;
fft_in_data[i][1] = resampleBuffer[i].imag;
}
}
} else {
num_written = data->size();
if (data->size() < fft_size) {
for (int i = 0, iMax = data->size(); i < iMax; i++) {
in[i][0] = (*data)[i].real;
in[i][1] = (*data)[i].imag;
fft_in_data[i][0] = (*data)[i].real;
fft_in_data[i][1] = (*data)[i].imag;
}
for (int i = data->size(); i < fft_size; i++) {
in[i][0] = 0;
in[i][1] = 0;
fft_in_data[i][0] = 0;
fft_in_data[i][1] = 0;
}
} else {
for (int i = 0; i < fft_size; i++) {
in[i][0] = (*data)[i].real;
in[i][1] = (*data)[i].imag;
fft_in_data[i][0] = (*data)[i].real;
fft_in_data[i][1] = (*data)[i].imag;
}
}
}
fftwf_execute(plan);
bool execute = false;
float fft_ceil = 0, fft_floor = 1;
if (num_written >= fft_size) {
execute = true;
memcpy(in, fft_in_data, sizeof(fftwf_complex) * fft_size * sizeof(fftwf_complex));
memcpy(fft_last_data, in, fft_size * sizeof(fftwf_complex));
if (fft_result.size() < fft_size) {
fft_result.resize(fft_size);
fft_result_ma.resize(fft_size);
fft_result_maa.resize(fft_size);
}
int n;
for (int i = 0, iMax = fft_size / 2; i < iMax; i++) {
n = (i == 0) ? 1 : i;
float a = out[n][0];
float b = out[n][1];
float c = sqrt(a * a + b * b);
float x = out[fft_size / 2 + n][0];
float y = out[fft_size / 2 + n][1];
float z = sqrt(x * x + y * y);
fft_result[i] = (z);
fft_result[fft_size / 2 + i] = (c);
}
for (int i = 0, iMax = fft_size; i < iMax; i++) {
if (isView) {
fft_result_maa[i] += (fft_result_ma[i] - fft_result_maa[i]) * 0.65;
fft_result_ma[i] += (fft_result[i] - fft_result_ma[i]) * 0.65;
} else {
if (last_data_size + num_written < fft_size) { // priming
unsigned int num_copy = fft_size;
num_copy = fft_size - last_data_size;
if (num_written > num_copy) {
num_copy = num_written;
}
memcpy(fft_last_data, fft_in_data, num_copy * sizeof(fftwf_complex));
last_data_size += num_copy;
} else {
fft_result_maa[i] += (fft_result_ma[i] - fft_result_maa[i]) * 0.65;
fft_result_ma[i] += (fft_result[i] - fft_result_ma[i]) * 0.65;
}
if (fft_result_maa[i] > fft_ceil) {
fft_ceil = fft_result_maa[i];
}
if (fft_result_maa[i] < fft_floor) {
fft_floor = fft_result_maa[i];
unsigned int num_last = (fft_size - num_written);
memcpy(in, fft_last_data + (last_data_size - num_last), num_last * sizeof(fftwf_complex));
memcpy(in + num_last, fft_in_data, num_written * sizeof(fftwf_complex));
memcpy(fft_last_data, in, fft_size * sizeof(fftwf_complex));
}
}
fft_ceil += 0.25;
fft_floor -= 1;
if (execute) {
fftwf_execute(plan);
fft_ceil_ma = fft_ceil_ma + (fft_ceil - fft_ceil_ma) * 0.05;
fft_ceil_maa = fft_ceil_maa + (fft_ceil_ma - fft_ceil_maa) * 0.05;
float fft_ceil = 0, fft_floor = 1;
fft_floor_ma = fft_floor_ma + (fft_floor - fft_floor_ma) * 0.05;
fft_floor_maa = fft_floor_maa + (fft_floor_ma - fft_floor_maa) * 0.05;
if (fft_result.size() < fft_size) {
fft_result.resize(fft_size);
fft_result_ma.resize(fft_size);
fft_result_maa.resize(fft_size);
}
for (int i = 0, iMax = fft_size; i < iMax; i++) {
float v = (log10(fft_result_maa[i] - fft_floor_maa) / log10(fft_ceil_maa - fft_floor_maa));
spectrum_points[i * 2] = ((float) i / (float) iMax);
spectrum_points[i * 2 + 1] = v;
}
int n;
for (int i = 0, iMax = fft_size / 2; i < iMax; i++) {
n = (i == 0) ? 1 : i;
float a = out[n][0];
float b = out[n][1];
float c = sqrt(a * a + b * b);
if (spectrumCanvas) {
spectrumCanvas->spectrum_points.assign(spectrum_points.begin(), spectrum_points.end());
float x = out[fft_size / 2 + n][0];
float y = out[fft_size / 2 + n][1];
float z = sqrt(x * x + y * y);
fft_result[i] = (z);
fft_result[fft_size / 2 + i] = (c);
}
for (int i = 0, iMax = fft_size; i < iMax; i++) {
if (isView) {
fft_result_maa[i] += (fft_result_ma[i] - fft_result_maa[i]) * 0.65;
fft_result_ma[i] += (fft_result[i] - fft_result_ma[i]) * 0.65;
} else {
fft_result_maa[i] += (fft_result_ma[i] - fft_result_maa[i]) * 0.65;
fft_result_ma[i] += (fft_result[i] - fft_result_ma[i]) * 0.65;
}
if (fft_result_maa[i] > fft_ceil) {
fft_ceil = fft_result_maa[i];
}
if (fft_result_maa[i] < fft_floor) {
fft_floor = fft_result_maa[i];
}
}
fft_ceil += 0.25;
fft_floor -= 1;
fft_ceil_ma = fft_ceil_ma + (fft_ceil - fft_ceil_ma) * 0.05;
fft_ceil_maa = fft_ceil_maa + (fft_ceil_ma - fft_ceil_maa) * 0.05;
fft_floor_ma = fft_floor_ma + (fft_floor - fft_floor_ma) * 0.05;
fft_floor_maa = fft_floor_maa + (fft_floor_ma - fft_floor_maa) * 0.05;
for (int i = 0, iMax = fft_size; i < iMax; i++) {
float v = (log10(fft_result_maa[i] - fft_floor_maa) / log10(fft_ceil_maa - fft_floor_maa));
spectrum_points[i * 2] = ((float) i / (float) iMax);
spectrum_points[i * 2 + 1] = v;
}
if (spectrumCanvas) {
spectrumCanvas->spectrum_points.assign(spectrum_points.begin(), spectrum_points.end());
}
}
}
}

View File

@ -56,7 +56,8 @@ private:
WaterfallCanvas *otherWaterfallCanvas;
bool polling;
fftwf_complex *in, *out;
fftwf_complex *in, *out, *fft_in_data, *fft_last_data;
unsigned int last_data_size;
fftwf_plan plan;
float fft_ceil_ma, fft_ceil_maa;
@ -84,6 +85,8 @@ private:
std::vector<liquid_float_complex> shiftBuffer;
std::vector<liquid_float_complex> resampleBuffer;
// event table
wxDECLARE_EVENT_TABLE();
};