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Completed curly bracket movement.

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Thomas Harte
2017-03-26 14:34:47 -04:00
parent 3229502fa1
commit e01f3f06c8
83 changed files with 1542 additions and 3077 deletions
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SignalProcessing/FIRFilter.cpp
+16 -31
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@@ -36,34 +36,28 @@ using namespace SignalProcessing;
#define kCSKaiserBesselFilterFixedMultiplier 32767.0f
#define kCSKaiserBesselFilterFixedShift 15
/* ino evaluates the 0th order Bessel function at a */
float FIRFilter::ino(float a)
{
/*! Evaluates the 0th order Bessel function at @c a. */
float FIRFilter::ino(float a) {
float d = 0.0f;
float ds = 1.0f;
float s = 1.0f;
do
{
do {
d += 2.0f;
ds *= (a * a) / (d * d);
s += ds;
}
while(ds > s*1e-6f);
} while(ds > s*1e-6f);
return s;
}
//static void csfilter_setIdealisedFilterResponse(short *filterCoefficients, float *A, float attenuation, unsigned int numberOfTaps)
void FIRFilter::coefficients_for_idealised_filter_response(short *filterCoefficients, float *A, float attenuation, unsigned int numberOfTaps)
{
void FIRFilter::coefficients_for_idealised_filter_response(short *filterCoefficients, float *A, float attenuation, unsigned int numberOfTaps) {
/* calculate alpha, which is the Kaiser-Bessel window shape factor */
float a; // to take the place of alpha in the normal derivation
if(attenuation < 21.0f)
if(attenuation < 21.0f) {
a = 0.0f;
else
{
} else {
if(attenuation > 50.0f)
a = 0.1102f * (attenuation - 8.7f);
else
@@ -76,8 +70,7 @@ void FIRFilter::coefficients_for_idealised_filter_response(short *filterCoeffici
unsigned int Np = (numberOfTaps - 1) / 2;
float I0 = ino(a);
float NpSquared = (float)(Np * Np);
for(unsigned int i = 0; i <= Np; i++)
{
for(unsigned int i = 0; i <= Np; i++) {
filterCoefficientsFloat[Np + i] =
A[i] *
ino(a * sqrtf(1.0f - ((float)(i * i) / NpSquared) )) /
@@ -85,38 +78,32 @@ void FIRFilter::coefficients_for_idealised_filter_response(short *filterCoeffici
}
/* coefficients are symmetrical, so copy from right hand side to left side */
for(unsigned int i = 0; i < Np; i++)
{
for(unsigned int i = 0; i < Np; i++) {
filterCoefficientsFloat[i] = filterCoefficientsFloat[numberOfTaps - 1 - i];
}
/* scale back up so that we retain 100% of input volume */
float coefficientTotal = 0.0f;
for(unsigned int i = 0; i < numberOfTaps; i++)
{
for(unsigned int i = 0; i < numberOfTaps; i++) {
coefficientTotal += filterCoefficientsFloat[i];
}
/* we'll also need integer versions, potentially */
float coefficientMultiplier = 1.0f / coefficientTotal;
for(unsigned int i = 0; i < numberOfTaps; i++)
{
for(unsigned int i = 0; i < numberOfTaps; i++) {
filterCoefficients[i] = (short)(filterCoefficientsFloat[i] * kCSKaiserBesselFilterFixedMultiplier * coefficientMultiplier);
}
delete[] filterCoefficientsFloat;
}
void FIRFilter::get_coefficients(float *coefficients)
{
for(unsigned int i = 0; i < number_of_taps_; i++)
{
void FIRFilter::get_coefficients(float *coefficients) {
for(unsigned int i = 0; i < number_of_taps_; i++) {
coefficients[i] = (float)filter_coefficients_[i] / kCSKaiserBesselFilterFixedMultiplier;
}
}
FIRFilter::FIRFilter(unsigned int number_of_taps, float input_sample_rate, float low_frequency, float high_frequency, float attenuation)
{
FIRFilter::FIRFilter(unsigned int number_of_taps, float input_sample_rate, float low_frequency, float high_frequency, float attenuation) {
// we must be asked to filter based on an odd number of
// taps, and at least three
if(number_of_taps < 3) number_of_taps = 3;
@@ -135,8 +122,7 @@ FIRFilter::FIRFilter(unsigned int number_of_taps, float input_sample_rate, float
float *A = new float[Np+1];
A[0] = 2.0f * (high_frequency - low_frequency) / input_sample_rate;
for(unsigned int i = 1; i <= Np; i++)
{
for(unsigned int i = 1; i <= Np; i++) {
float iPi = (float)i * (float)M_PI;
A[i] =
(
@@ -151,7 +137,6 @@ FIRFilter::FIRFilter(unsigned int number_of_taps, float input_sample_rate, float
delete[] A;
}
FIRFilter::~FIRFilter()
{
FIRFilter::~FIRFilter() {
delete[] filter_coefficients_;
}