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Diffstat (limited to 'sms/filters.c')
-rw-r--r--sms/filters.c73
1 files changed, 24 insertions, 49 deletions
diff --git a/sms/filters.c b/sms/filters.c
index b1ca9fc..9c13ad5 100644
--- a/sms/filters.c
+++ b/sms/filters.c
@@ -31,13 +31,11 @@
*
* sfloat fInput; sound sample
*/
-sfloat sms_preEmphasis (sfloat fInput, SMS_AnalParams *pAnalParams)
+sfloat sms_preEmphasis(sfloat fInput, SMS_AnalParams *pAnalParams)
{
- sfloat fOutput = 0;
- fOutput = fInput - SMS_EMPH_COEF * pAnalParams->preEmphasisLastValue;
- pAnalParams->preEmphasisLastValue = fOutput;
-
- return (fOutput);
+ sfloat fOutput = fInput - SMS_EMPH_COEF * pAnalParams->preEmphasisLastValue;
+ pAnalParams->preEmphasisLastValue = fOutput;
+ return fOutput;
}
/* de-emphasis filter function, it returns the filtered value
@@ -46,11 +44,9 @@ sfloat sms_preEmphasis (sfloat fInput, SMS_AnalParams *pAnalParams)
*/
sfloat sms_deEmphasis(sfloat fInput, SMS_SynthParams *pSynthParams)
{
- sfloat fOutput = 0;
- fOutput = fInput + SMS_EMPH_COEF * pSynthParams->deemphasisLastValue;
- pSynthParams->deemphasisLastValue = fInput;
-
- return(fOutput);
+ sfloat fOutput = fInput + SMS_EMPH_COEF * pSynthParams->deEmphasisLastValue;
+ pSynthParams->deEmphasisLastValue = fInput;
+ return fOutput;
}
/*! \brief function to implement a zero-pole filter
@@ -65,15 +61,11 @@ sfloat sms_deEmphasis(sfloat fInput, SMS_SynthParams *pSynthParams)
* \param fInput input sample
* \return value is the filtered sample
*/
-static sfloat ZeroPoleFilter (sfloat *pFa, sfloat *pFb, int nCoeff, sfloat fInput )
+static sfloat ZeroPoleFilter(sfloat *pFa, sfloat *pFb, int nCoeff, sfloat fInput )
{
double fOut = 0;
int iSection;
-
-/* static sfloat *pD = NULL; */
-/* if (pD == NULL) */
-/* pD = (sfloat *) calloc(5, sizeof(sfloat)); */
- static sfloat pD[5] = {0, 0, 0, 0, 0};
+ static sfloat pD[5] = {0, 0, 0, 0, 0};
pD[0] = fInput;
for (iSection = nCoeff-1; iSection > 0; iSection--)
@@ -83,23 +75,9 @@ static sfloat ZeroPoleFilter (sfloat *pFa, sfloat *pFb, int nCoeff, sfloat fInpu
pD[iSection] = pD [iSection-1];
}
fOut = fOut + pFa[0] * pD[0];
- return((sfloat) fOut);
+ return (sfloat) fOut;
}
- /* cutoff 1500 Hz */
-/* static sfloat pFCoeff32k[10] = {0.679459, -2.71784, 4.07676, -2.71784,
- 0.679459, 1, -3.23168, 3.97664, -2.20137, 0.461665};
- static sfloat pFCoeff36k[10] = {0.709489, -2.83796, 4.25694, -2.83796,
- 0.709489, 1, -3.31681, 4.17425, -2.3574, 0.503375};
- static sfloat pFCoeff40k[10] = {0.734408, -2.93763, 4.40645, -2.93763,
- 0.734408, 1, -3.38497, 4.33706, -2.48914, 0.539355};
- static sfloat pFCoeff441k[10] = {0.755893, -3.02357, 4.53536, -3.02357,
- 0.755893, 1, -3.44205, 4.47657, -2.6043, 0.571374};
- static sfloat pFCoeff48k[10] = {0.773347, -3.09339, 4.64008, -3.09339,
- 0.773347, 1, -3.48731, 4.58929, -2.69888, 0.598065};
-*/
-
-
/*! \brief function to filter a waveform with a high-pass filter
*
* cutoff =1500 Hz
@@ -110,10 +88,8 @@ static sfloat ZeroPoleFilter (sfloat *pFa, sfloat *pFb, int nCoeff, sfloat fInpu
* \param pResidual pointer to residual signal
* \param iSamplingRate sampling rate of signal
*/
-void sms_filterHighPass ( int sizeResidual, sfloat *pResidual, int iSamplingRate)
+void sms_filterHighPass(int sizeResidual, sfloat *pResidual, int iSamplingRate)
{
-
-
/* cutoff 800Hz */
static sfloat pFCoeff32k[10] = {0.814255, -3.25702, 4.88553, -3.25702,
0.814255, 1, -3.58973, 4.85128, -2.92405, 0.66301};
@@ -128,13 +104,13 @@ void sms_filterHighPass ( int sizeResidual, sfloat *pResidual, int iSamplingRate
sfloat *pFCoeff, fSample = 0;
int i;
- if (iSamplingRate <= 32000)
+ if(iSamplingRate <= 32000)
pFCoeff = pFCoeff32k;
- else if (iSamplingRate <= 36000)
+ else if(iSamplingRate <= 36000)
pFCoeff = pFCoeff36k;
- else if (iSamplingRate <= 40000)
+ else if(iSamplingRate <= 40000)
pFCoeff = pFCoeff40k;
- else if (iSamplingRate <= 44100)
+ else if(iSamplingRate <= 44100)
pFCoeff = pFCoeff441k;
else
pFCoeff = pFCoeff48k;
@@ -142,12 +118,11 @@ void sms_filterHighPass ( int sizeResidual, sfloat *pResidual, int iSamplingRate
for(i = 0; i < sizeResidual; i++)
{
/* try to avoid underflow when there is nothing to filter */
- if (i > 0 && fSample == 0 && pResidual[i] == 0)
+ if(i > 0 && fSample == 0 && pResidual[i] == 0)
return;
fSample = pResidual[i];
- pResidual[i] =
- ZeroPoleFilter (&pFCoeff[0], &pFCoeff[5], 5, fSample);
+ pResidual[i] = ZeroPoleFilter (&pFCoeff[0], &pFCoeff[5], 5, fSample);
}
}
@@ -161,32 +136,32 @@ void sms_filterHighPass ( int sizeResidual, sfloat *pResidual, int iSamplingRate
* \param size2 horizontal size of pFArray
* \param pFOutArray output array of size size1
*/
-void sms_filterArray (sfloat *pFArray, int size1, int size2, sfloat *pFOutArray)
+void sms_filterArray(sfloat *pFArray, int size1, int size2, sfloat *pFOutArray)
{
int i, j, iPoint, iFrame, size2_2 = size2-2, size2_1 = size2-1;
sfloat *pFCurrentArray = pFArray + (size2_1) * size1;
- sfloat fVal, fWeighting, fTotalWeighting, fTmpVal;
+ sfloat fVal, fWeighting, fTotalWeighting, fTmpVal;
/* find the filtered envelope */
- for (i = 0; i < size1; i++)
+ for(i = 0; i < size1; i++)
{
fVal = pFCurrentArray[i];
fTotalWeighting = 1;
/* filter by the surrounding points */
- for (j = 1; j < (size2_2); j++)
+ for(j = 1; j < (size2_2); j++)
{
fWeighting = (sfloat) size2 / (1+ j);
/* filter on the vertical dimension */
/* consider the lower points */
iPoint = i - (size2_1) + j;
- if (iPoint >= 0)
+ if(iPoint >= 0)
{
fVal += pFCurrentArray[iPoint] * fWeighting;
fTotalWeighting += fWeighting;
}
/* consider the higher points */
iPoint = i + (size2_1) - j;
- if (iPoint < size1)
+ if(iPoint < size1)
{
fVal += pFCurrentArray[iPoint] * fWeighting;
fTotalWeighting += fWeighting;
@@ -195,7 +170,7 @@ void sms_filterArray (sfloat *pFArray, int size1, int size2, sfloat *pFOutArray)
/* consider the previous points */
iFrame = j;
fTmpVal = pFArray[iFrame*size1 + i];
- if (fTmpVal)
+ if(fTmpVal)
{
fVal += fTmpVal * fWeighting;
fTotalWeighting += fWeighting;
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-06 21:50:26 +0000