1 files changed, 78 insertions, 0 deletions
diff --git a/sms/stocAnalysis.c b/sms/stocAnalysis.c
new file mode 100644
index 0000000..27d5e4b
--- /dev/null
+++ b/sms/stocAnalysis.c
@@ -0,0 +1,78 @@
+/* 
+ * Copyright (c) 2008 MUSIC TECHNOLOGY GROUP (MTG)
+ *                         UNIVERSITAT POMPEU FABRA 
+ * 
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, M  02111-1307  USA
+ * 
+ */
+/*! \file stocAnalysis.c
+ * \brief stochastic analysis using spectral analysis and approximation
+ */
+#include "sms.h"
+
+#define ENV_THRESHOLD     .01 /* \todo was this value for type shorts?? */
+
+/*! \brief main function for the stochastic analysis
+ * \param sizeWindow         size of buffer
+ * \param pResidual      pointer to residual signal
+ * \param pWindow      pointer to windowing array
+ * \param pSmsData        pointer to output SMS data
+ * \return 0 on success, -1 on error
+ */
+int sms_stocAnalysis ( int sizeWindow, sfloat *pResidual, sfloat *pWindow, SMS_Data *pSmsData)
+{
+        int i;
+        sfloat fMag = 0.0;
+        float fStocNorm;
+
+        static sfloat *pMagSpectrum;
+        static int sizeWindowStatic = 0;
+        static int sizeFft = 0;
+        static int sizeMag = 0;
+        /* update array sizes if sizeWindow is new */
+        if (sizeWindowStatic != sizeWindow)
+        {
+                if(sizeWindowStatic != 0) free(pMagSpectrum);
+                sizeWindowStatic = sizeWindow;
+                sizeFft = sms_power2(sizeWindow);
+                sizeMag = sizeFft >> 1;
+                if((pMagSpectrum = (sfloat *) calloc(sizeMag, sizeof(sfloat))) == NULL)
+                {
+                        sms_error("sms_stocAnalysis: error allocating memory for pMagSpectrum");
+                        return -1;
+                }
+        }
+        
+        sms_spectrumMag (sizeWindow, pResidual, pWindow, sizeMag, pMagSpectrum);
+ 
+        sms_spectralApprox (pMagSpectrum, sizeMag, sizeMag, pSmsData->pFStocCoeff, 
+                            pSmsData->nCoeff, pSmsData->nCoeff);
+  
+        /* get energy of spectrum  */
+        for (i = 0; i < sizeMag; i++)
+                fMag += (pMagSpectrum[i] * pMagSpectrum[i]);
+        *pSmsData->pFStocGain = fMag / sizeMag;
+        fStocNorm = 1. / *pSmsData->pFStocGain;
+
+        /* normalize envelope */
+        /* \todo what good is this scaling, it is only being undone in resynthesis */
+/*         for (i = 0; i <  pSmsData->nCoeff; i++) */
+/*                 pSmsData->pFStocCoeff[i] *= fStocNorm; */
+    
+        // *pSmsData->pFStocGain = sms_magToDB(*pSmsData->pFStocGain);
+	return(0);
+}
+