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DPL2Decoder: Remove unnecessary pointer arguments of DesignFIR

This commit is contained in:
MerryMage 2017-04-22 09:46:39 +01:00
parent b5c857d14b
commit d0e75bb438
1 changed files with 12 additions and 14 deletions
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26
Source/Core/AudioCommon/DPL2Decoder.cpp
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@ -105,9 +105,7 @@ static void Hamming(int n, float* w)
*w++ = float(0.54 - 0.46 * cos(k * (float)i));
}
/******************************************************************************
* FIR filter design
******************************************************************************/
// FIR filter design
/* Design FIR filter using the Window method
@ -122,10 +120,10 @@ opt beta constant used only when designing using kaiser windows
returns 0 if OK, -1 if fail
*/
static float* DesignFIR(unsigned int* n, float* fc, float opt)
static float* DesignFIR(unsigned int n, float fc, float opt)
{
unsigned int o = *n & 1; // Indicator for odd filter length
unsigned int end = ((*n + 1) >> 1) - o; // Loop end
unsigned int o = n & 1; // Indicator for odd filter length
unsigned int end = ((n + 1) >> 1) - o; // Loop end
float k1 = 2 * float(M_PI); // 2*pi*fc1
float k2 = 0.5f * (float)(1 - o); // Constant used if the filter has even length
@ -134,17 +132,17 @@ static float* DesignFIR(unsigned int* n, float* fc, float opt)
float fc1; // Cutoff frequencies
// Sanity check
if (*n == 0)
if (n == 0)
return nullptr;
fc[0] = MathUtil::Clamp(fc[0], 0.001f, 1.0f);
fc = MathUtil::Clamp(fc, 0.001f, 1.0f);
float* w = (float*)calloc(sizeof(float), *n);
float* w = (float*)calloc(sizeof(float), n);
// Get window coefficients
Hamming(*n, w);
Hamming(n, w);
fc1 = *fc;
fc1 = fc;
// Cutoff frequency must be < 0.5 where 0.5 <=> Fs/2
fc1 = ((fc1 <= 1.0) && (fc1 > 0.0)) ? fc1 / 2 : 0.25f;
k1 *= fc1;
@ -165,13 +163,13 @@ static float* DesignFIR(unsigned int* n, float* fc, float opt)
for (u32 i = 0; i < end; i++)
{
t1 = (float)(i + 1) - k2;
w[end - i - 1] = w[*n - end + i] = float(w[end - i - 1] * sin(k1 * t1) / (M_PI * t1)); // Sinc
w[end - i - 1] = w[n - end + i] = float(w[end - i - 1] * sin(k1 * t1) / (M_PI * t1)); // Sinc
g += 2 * w[end - i - 1]; // Total gain in filter
}
// Normalize gain
g = 1 / g;
for (u32 i = 0; i < *n; i++)
for (u32 i = 0; i < n; i++)
w[i] *= g;
return w;
@ -209,7 +207,7 @@ static float* CalculateCoefficients125HzLowpass(int rate)
{
len125 = 256;
float f = 125.0f / (rate / 2);
float* coeffs = DesignFIR(&len125, &f, 0);
float* coeffs = DesignFIR(len125, f, 0);
static const float M3_01DB = 0.7071067812f;
for (unsigned int i = 0; i < len125; i++)
{