/* Demo 2 */
void GenerateAndTest2(FLOATING frequency)
{
int index;
FLOATING magnitudeSquared;
FLOATING magnitude;
FLOATING real;
FLOATING imag;
printf("Freq=%7.1f ", frequency);
Generate(frequency);
/* Process the samples. */
for (index = 0; index < N; index++)
{
ProcessSample(testData[index]);
}
/* Do the "standard Goertzel" processing. */
GetRealImag(&real, &imag);
magnitudeSquared = real*real + imag*imag;
printf("rel mag^2=%16.5f ", magnitudeSquared);
magnitude = sqrt(magnitudeSquared);
printf("rel mag=%12.5f\n", magnitude);
ResetGoertzel();
}
static void setUpConstants()
{
int i;
for( i = 0; i < MAX_BINS; i++) {
ks[i] = (int)(0.5 + (NS[i]*FREQUENCIES[i]/SAMPLING_RATE));
est_freqs[i] = (float)((int)(0.5 + (((float)ks[i])*SAMPLING_RATE/NS[i])));
}
ResetGoertzel();
}
/* Call this each time a frequency is tested, to precompute the constants. */
static void InitGoertzel(const int i)
{
FLOATING floatN;
FLOATING omega;
int k;
floatN = (FLOATING) NS[i];
k = (int) (ks[i]);
omega = (2.0 * PI * k) / floatN;
sine = sin(omega);
cosine = cos(omega);
coeff = 2.0 * cosine;
ResetGoertzel();
}
float Goertzel::detect()
{
float magnitude;
/* Process the samples. */
for (int index = 0; index < _N; index++)
{
ProcessSample(testData[index]);
}
/* Do the "standard Goertzel" processing. */
magnitude = sqrt(Q1*Q1 + Q2*Q2 - coeff*Q1*Q2);
ResetGoertzel();
return magnitude;
}
void Goertzel::ChangeParameters(float TARGET_FREQUENCY, float N, float SAMPLING_FREQUENCY)
{
_SAMPLING_FREQUENCY=SAMPLING_FREQUENCY; //on 16mhz, ~8928.57142857143, on 8mhz ~44444
_TARGET_FREQUENCY=TARGET_FREQUENCY; //should be integer of SAMPLING_RATE/N
if(N>MAXN){
_N=MAXN;
}else{
_N=N;
}
float omega = (2.0 * PI * _TARGET_FREQUENCY) / _SAMPLING_FREQUENCY;
coeff = 2.0 * cos(omega);
ResetGoertzel();
}
/* Call this once, to precompute the constants. */
void InitGoertzel(void)
{
int k;
FLOATING floatN;
FLOATING omega;
floatN = (FLOATING) N;
k = (int) (0.5 + ((floatN * TARGET_FREQUENCY) / SAMPLING_RATE));
omega = (2.0 * PI * k) / floatN;
sine = sin(omega);
cosine = cos(omega);
coeff = 2.0 * cosine;
printf("For SAMPLING_RATE = %f", SAMPLING_RATE);
printf(" N = %d", N);
printf(" and FREQUENCY = %f,\n", TARGET_FREQUENCY);
printf("k = %d and coeff = %f\n\n", k, coeff);
ResetGoertzel();
}
/* Test the given data */
static FLOATING Test(int i, const SAMPLE *input)
{
int index;
FLOATING magnitudeSquared;
FLOATING magnitude;
FLOATING real;
FLOATING imag;
/* Process the samples. */
for (index = 0; index < NS[i]; index++)
{
ProcessSample(input[index]); // instead of processing the testData, process the actual sound file so long as the constants agree (no need to generate)
}
/* Do the "standard Goertzel" processing. */
real = (Q1 - Q2 * cosine);
imag = (Q2 * sine);
magnitudeSquared = real*real + imag*imag;
magnitude = sqrt(magnitudeSquared);
return magnitude;
ResetGoertzel();
}
/* Demo 1 */
void GenerateAndTest(FLOATING frequency)
{
int index;
FLOATING magnitudeSquared;
FLOATING magnitude;
FLOATING real;
FLOATING imag;
printf("For test frequency %f:\n", frequency);
Generate(frequency);
/* Process the samples */
for (index = 0; index < N; index++)
{
ProcessSample(testData[index]);
}
/* Do the "basic Goertzel" processing. */
GetRealImag(&real, &imag);
printf("real = %f imag = %f\n", real, imag);
magnitudeSquared = real*real + imag*imag;
printf("Relative magnitude squared = %f\n", magnitudeSquared);
magnitude = sqrt(magnitudeSquared);
printf("Relative magnitude = %f\n", magnitude);
/* Do the "optimized Goertzel" processing */
magnitudeSquared = GetMagnitudeSquared();
printf("Relative magnitude squared = %f\n", magnitudeSquared);
magnitude = sqrt(magnitudeSquared);
printf("Relative magnitude = %f\n\n", magnitude);
ResetGoertzel();
}
