some more work for multiple sample rate support

src/channel.cpp

@@ -1160,7 +1160,9 @@ EPutDataStat CChannel::PutData ( const CVector<uint8_t>& vecbyData,
                         // on the system sample rate, therefore we use the
                         // decompressed audio buffer size instead of the network
                         // buffer size)
-                        CycleTimeVariance.Init ( iAudioSize, TIME_MOV_AV_RESPONSE );
+                        CycleTimeVariance.Init ( iAudioSize,
+                            SYSTEM_SAMPLE_RATE, TIME_MOV_AV_RESPONSE );
+
                         CycleTimeVariance.Reset();
                     }
                     else

src/client.cpp

@@ -303,7 +303,8 @@ void CClient::Init ( const int iSampleRate,
     vecdNetwData.Init ( iMonoBlockSizeSam );
 
     // init response time evaluation
-    CycleTimeVariance.Init ( iMonoBlockSizeSam, TIME_MOV_AV_RESPONSE );
+    CycleTimeVariance.Init ( iMonoBlockSizeSam,
+        iClientSampleRate, TIME_MOV_AV_RESPONSE );
 
     CycleTimeVariance.Reset();
 

src/resample.cpp

@@ -4,13 +4,6 @@
  * Author(s):
  *  Volker Fischer
  *
- * Description:
- * Resample routine for arbitrary sample-rate conversions in a low range.
- * The algorithm is based on a polyphase structure. We upsample the input
- * signal with a factor INTERP_DECIM_I_D1 and calculate two successive samples
- * whereby we perform a linear interpolation between these two samples to get
- * an arbitraty sample grid.
- *
  * The polyphase filter is calculated with Matlab, the associated file
  * is ResampleFilter.m.
  *
@@ -156,6 +149,9 @@ void CStereoAudioResample::Init ( const int iNewMonoInputBlockSize,
     // set correct parameters
     if ( iFrom >= iTo ) // downsampling case
     {
+        if ( iFrom == SND_CRD_SAMPLE_RATE )
+        {
+            // sound card resampling
             switch ( iTo )
             {
             case ( SND_CRD_SAMPLE_RATE / 2 ): // 48 kHz to 24 kHz
@@ -189,8 +185,28 @@ void CStereoAudioResample::Init ( const int iNewMonoInputBlockSize,
                 break;
             }
         }
-    else // upsampling case (assumption: iTo == SND_CRD_SAMPLE_RATE)
+        else
         {
+            // general sampling rate conversion
+            if ( ( iFrom == 32000 ) && ( iTo == 24000 ) )
+            {
+                // 32 kHz to 24 kHz
+                pFiltTaps = fResTaps4_3;
+                iNumTaps  = INTERP_I_4_3 * NUM_TAPS_PER_PHASE4_3;
+                iI        = DECIM_D_4_3;
+            }
+            else
+            {
+                // resample ratio not defined, throw error
+                throw 0;
+            }
+        }
+    }
+    else // upsampling case
+    {
+        if ( iTo == SND_CRD_SAMPLE_RATE )
+        {
+            // sound card resampling
             switch ( iFrom )
             {
             case ( SND_CRD_SAMPLE_RATE / 2 ): // 24 kHz to 48 kHz
@@ -217,6 +233,23 @@ void CStereoAudioResample::Init ( const int iNewMonoInputBlockSize,
                 break;
             }
         }
+        else
+        {
+            // general sampling rate conversion
+            if ( ( iFrom == 24000 ) && ( iTo == 32000 ) )
+            {
+                // 24 kHz to 32 kHz
+                pFiltTaps = fResTaps4_3;
+                iNumTaps  = DECIM_D_4_3 * NUM_TAPS_PER_PHASE4_3;
+                iI        = INTERP_I_4_3;
+            }
+            else
+            {
+                // resample ratio not defined, throw error
+                throw 0;
+            }
+        }
+    }
 
     // allocate memory for internal buffer, clear sample history (for
     // the stereo case we have to consider that two times the number of taps of

src/server.cpp

@@ -38,8 +38,8 @@ CServer::CServer ( const QString& strLoggingFileName,
     vecsSendData.Init ( MIN_SERVER_BLOCK_SIZE_SAMPLES );
 
     // init moving average buffer for response time evaluation
-    CycleTimeVariance.Init (
+    CycleTimeVariance.Init ( MIN_SERVER_BLOCK_SIZE_SAMPLES,
-        MIN_SERVER_BLOCK_SIZE_SAMPLES, TIME_MOV_AV_RESPONSE );
+        SYSTEM_SAMPLE_RATE, TIME_MOV_AV_RESPONSE );
 
     // connect timer timeout signal
     QObject::connect ( &Timer, SIGNAL ( timeout() ),

src/util.h

@@ -556,14 +556,16 @@ public:
     virtual ~CCycleTimeVariance() {}
 
     void Init ( const int iNewBlockLengthAtSystemSampleRate,
+                const int iNewSystemSampleRate,
                 const int iHistoryLengthTime )
     {
-        // store block size
+        // store block size and sample rate
         iBlockLengthAtSystemSampleRate = iNewBlockLengthAtSystemSampleRate;
+        iSystemSampleRate              = iNewSystemSampleRate;
 
         // calculate actual moving average length and initialize buffer
         RespTimeMoAvBuf.Init ( iHistoryLengthTime *
-            SYSTEM_SAMPLE_RATE / iNewBlockLengthAtSystemSampleRate );
+            iNewSystemSampleRate / iNewBlockLengthAtSystemSampleRate );
     }
 
     int GetBlockLength() { return iBlockLengthAtSystemSampleRate; }
@@ -582,7 +584,7 @@ public:
         // we want to calculate the standard deviation (we assume that the mean
         // is correct at the block period time)
         const double dCurAddVal = ( (double) ( CurTime - TimeLastBlock ) -
-            ( iBlockLengthAtSystemSampleRate * 1000 / SYSTEM_SAMPLE_RATE ) );
+            ( iBlockLengthAtSystemSampleRate * 1000 / iSystemSampleRate ) );
 
         RespTimeMoAvBuf.Add ( dCurAddVal * dCurAddVal ); // add squared value
 
@@ -601,6 +603,7 @@ protected:
     CMovingAv<double> RespTimeMoAvBuf;
     int               TimeLastBlock;
     int               iBlockLengthAtSystemSampleRate;
+    int               iSystemSampleRate;
 };
 
 #endif /* !defined ( UTIL_HOIH934256GEKJH98_3_43445KJIUHF1912__INCLUDED_ ) */