float
Math::Log(
float arg,
float base
)
{
return (base==10.0f) ? Log10(arg) : (Log10(arg) / Log10(base));
} // Math::Log
void CChannelEstimation::GetTransferFunction(CVector<_REAL>& vecrData,
CVector<_REAL>& vecrGrpDly)
{
/* Init output vectors */
vecrData.Init(iNumCarrier, (_REAL) 0.0);
vecrGrpDly.Init(iNumCarrier, (_REAL) 0.0);
/* Do copying of data only if vector is of non-zero length which means that
the module was already initialized */
if (iNumCarrier != 0)
{
_REAL rDiffPhase, rOldPhase;
/* Lock resources */
Lock();
/* Init constant for normalization */
const _REAL rTu = (CReal) iFFTSizeN / SOUNDCRD_SAMPLE_RATE;
/* Copy data in output vector and set scale
(carrier index as x-scale) */
for (int i = 0; i < iNumCarrier; i++)
{
/* Transfer function */
CReal rNormChanEst = Abs(veccChanEst[i]) / (CReal) iNumCarrier;
if (rNormChanEst > 0)
vecrData[i] = (CReal) 20.0 * Log10(rNormChanEst);
else
vecrData[i] = RET_VAL_LOG_0;
/* Group delay */
if (i == 0)
{
/* At position 0 we cannot calculate a derivation -> use
the same value as position 0 */
rDiffPhase = Angle(veccChanEst[1]) - Angle(veccChanEst[0]);
}
else
rDiffPhase = Angle(veccChanEst[i]) - rOldPhase;
/* Take care of wrap around of angle() function */
if (rDiffPhase > WRAP_AROUND_BOUND_GRP_DLY)
rDiffPhase -= 2.0 * crPi;
if (rDiffPhase < -WRAP_AROUND_BOUND_GRP_DLY)
rDiffPhase += 2.0 * crPi;
/* Apply normalization */
vecrGrpDly[i] = rDiffPhase * rTu * 1000.0 /* ms */;
/* Store old phase */
rOldPhase = Angle(veccChanEst[i]);
}
/* Release resources */
Unlock();
}
}
/* Bogus random spiky-looking function to simulate a QA value,
which hovers within +/- 10% of perfect (100%), but
with relatively infrequent spiky errors */
int TfrmMain::_QAProblemScatter()
{
double n,m;
randomize();
n = Log10(random(10000)+1); // Random is my favourite function. How about you? -WP
n = n * Log10(random(10000)+1);
m = Log10(random(10000)+1);
m = m * Log10(random(10000)+1);
n = abs(100 + n - m);
if (n<0)
n = 0;
if (n>150)
n = 150;
return floor(n+0.5);
}
char*
UnsignedIntToCharPointer(unsigned int x) {
unsigned int n = Log10(x) + 1;
char* nArray = (char*)calloc(n + 1, sizeof(char));
for(unsigned int i = 0; i < n; ++i, n /= 10) {
nArray[i] = (x % 10) + '0';
}
return(nArray);
}
void main()
{
vec3 EyePosition = vec3(gl_ModelViewMatrix * vec4(gl_Vertex.xyz, 1.0));
vec3 VertexPosition = vec3(gl_ModelViewProjectionMatrix * gl_Vertex);
// z = log(z / zn) / log(zf / zn)
vec3 Extents = vec3(gl_ModelViewMatrix * vec4(BoxSize, BoxSize, BoxSize, 1.0));
float maxd = length(Extents);
float dist = length(EyePosition); // / maxd;
float pscale = PointScale;
vDistance = (pscale / dist / maxd);
vPointSize = ParticleRadius * (pscale / dist);
vIncident = normalize(-VertexPosition);
vDensity = LinearRemap(Log10(ParticleDensity), Log10(DensityRange.x), Log10(DensityRange.y), 0.0, 1.0);
vColor = ParticleColor;
vEye = EyePosition;
gl_PointSize = vPointSize;
gl_TexCoord[0] = gl_MultiTexCoord0;
gl_Position = gl_ModelViewProjectionMatrix * vec4(gl_Vertex.xyz, 1.0);
gl_FrontColor = gl_Color;
}
static base_t my_log10p1(const base_t &i)
{
return Log10(i+1.0);
}
static base_t my_log10(const base_t &i)
{
return Log10(i);
}
void CookbookEq::computeFilterCoefs()
{
float tmp = 0.0f;
float omega, sn, cs, alpha, beta;
bool zeroCoefs = false; // this is used if the freq is too high
// do not allow frequencies bigger than samplerate/2
float freq = _freq;
if (freq > (static_cast<float>(_sampleRate) / 2.0f - 500.0f))
{
freq = static_cast<float>(_sampleRate) / 2.0f - 500.0f;
zeroCoefs = true;
}
freq = std::max(freq, 0.1f);
const float gain = static_cast<float>(::exp(_gainDb * Log10() / 20.0));
// do not allow bogus Q
float q = std::max(_q, 0.0f);
// most of theese are implementations of
// the "Cookbook formulae for audio EQ" by Robert Bristow-Johnson
switch (_type)
{
case LoPass1:
if (!zeroCoefs)
{
tmp = static_cast<float>(::exp(-2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate)));
}
_c[0] = 1.0f - tmp;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = tmp;
_d[2] = 0.0f;
_order = 1;
break;
case HiPass1:
if (!zeroCoefs)
{
tmp = static_cast<float>(::exp(-2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate)));
}
_c[0] = (1.0f + tmp) / 2.0f;
_c[1] = -(1.0f + tmp) / 2.0f;
_c[2] = 0.0f;
_d[1] = tmp;
_d[2] = 0.0f;
_order = 1;
break;
case LoPass2:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin (omega);
cs = cos (omega);
alpha = sn / (2.0f * q);
tmp = 1.0f + alpha;
_c[0] = (1.0f - cs) / 2.0f / tmp;
_c[1] = (1.0f - cs) / tmp;
_c[2] = (1.0f - cs) / 2.0f / tmp;
_d[1] = -2.0f * cs / tmp * (-1.0f);
_d[2] = (1.0f - alpha) / tmp * (-1.0f);
}
else
{
_c[0] = 1.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case HiPass2:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin (omega);
cs = cos (omega);
alpha = sn / (2.0f * q);
tmp = 1.0f + alpha;
_c[0] = (1.0f + cs) / 2.0f / tmp;
_c[1] = -(1.0f + cs) / tmp;
_c[2] = (1.0f + cs) / 2.0f / tmp;
_d[1] = -2.0f * cs / tmp * (-1.0f);
_d[2] = (1.0f - alpha) / tmp * (-1.0f);
}
else
{
_c[0] = 0.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case BandPass:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin(omega);
cs = cos(omega);
alpha = sn / (2.0f * q);
tmp = 1.0f + alpha;
_c[0] = alpha / tmp * sqrt (q + 1.0f);
_c[1] = 0.0f;
_c[2] = -alpha / tmp * sqrt (q + 1.0f);
_d[1] = -2.0f * cs / tmp * (-1.0f);
_d[2] = (1.0f - alpha) / tmp * (-1.0f);
}
else
{
_c[0] = 0.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case Notch:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin(omega);
cs = cos(omega);
alpha = sn / (2 * sqrt (q));
tmp = 1.0f + alpha;
_c[0] = 1.0f / tmp;
_c[1] = -2.0f * cs / tmp;
_c[2] = 1.0f / tmp;
_d[1] = -2.0f * cs / tmp * (-1.0f);
_d[2] = (1.0f - alpha) / tmp * (-1.0f);
}
else
{
_c[0] = 1.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case Peak:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin(omega);
cs = cos(omega);
q *= 3.0;
alpha = sn / (2 * q);
tmp = 1 + alpha / gain;
_c[0] = (1.0f + alpha * gain) / tmp;
_c[1] = (-2.0f * cs) / tmp;
_c[2] = (1.0f - alpha * gain) / tmp;
_d[1] = -2.0f * cs / tmp * (-1.0f);
_d[2] = (1.0f - alpha / gain) / tmp * (-1.0f);
}
else
{
_c[0] = 1.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case LoShelf:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin (omega);
cs = cos (omega);
q = sqrt (q);
alpha = sn / (2 * q);
beta = sqrt (gain) / q;
tmp = (gain + 1.0f) + (gain - 1.0f) * cs + beta * sn;
_c[0] = gain * ((gain + 1.0f) - (gain - 1.0f) * cs + beta * sn) / tmp;
_c[1] = 2.0f * gain * ((gain - 1.0f) - (gain + 1.0f) * cs) / tmp;
_c[2] = gain * ((gain + 1.0f) - (gain - 1.0f) * cs - beta * sn) / tmp;
_d[1] = -2.0f * ((gain - 1.0f) + (gain + 1.0f) * cs) / tmp * (-1.0f);
_d[2] = ((gain + 1.0f) + (gain - 1.0f) * cs - beta * sn) / tmp * (-1.0f);
}
else
{
_c[0] = gain;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
case HiShelf:
if (!zeroCoefs)
{
omega = static_cast<float>(2.0 * Pi() * static_cast<double>(freq) / static_cast<double>(_sampleRate));
sn = sin(omega);
cs = cos(omega);
q = sqrt(q);
alpha = sn / (2.0f * q);
beta = sqrt (gain) / q;
tmp = (gain + 1.0f) - (gain - 1.0f) * cs + beta * sn;
_c[0] = gain * ((gain + 1.0f) + (gain - 1.0f) * cs + beta * sn) / tmp;
_c[1] = -2.0f * gain * ((gain - 1.0f) + (gain + 1.0f) * cs) / tmp;
_c[2] = gain * ((gain + 1.0f) + (gain - 1.0f) * cs - beta * sn) / tmp;
_d[1] = 2.0f * ((gain - 1.0f) - (gain + 1.0f) * cs) / tmp * (-1.0f);
_d[2] = ((gain + 1.0f) - (gain - 1.0f) * cs - beta * sn) / tmp * (-1.0f);
}
else
{
_c[0] = 1.0f;
_c[1] = 0.0f;
_c[2] = 0.0f;
_d[1] = 0.0f;
_d[2] = 0.0f;
}
_order = 2;
break;
default: // wrong type
assert(false);
break;
}
}
