[#3487] Improve notch filter for DC component removal

sflphone-common/src/audio/alsa/alsalayer.cpp

@@ -1125,9 +1125,15 @@ void AlsaLayer::audioCallback(void)
 
                 } else {
 
-		    int sampleready = AudioLayer::_echoCanceller->processAudio(in, echoCancelledMic, toPut);
+		  
+		    SFLDataFormat* filter_out = (SFLDataFormat*) malloc (framesPerBufferAlsa * sizeof (SFLDataFormat));
+
+		    _audiofilter->processAudio (in, filter_out, toPut);
+		  
+		    int sampleready = AudioLayer::_echoCanceller->processAudio(filter_out, echoCancelledMic, toPut);
 
                     getMainBuffer()->putData (echoCancelledMic, sampleready*sizeof(SFLDataFormat), 100);
+		    free(rsmpl_out);
                 }
             }
 

sflphone-common/src/audio/dcblocker.cpp

@@ -77,7 +77,7 @@ void DcBlocker::process (SFLDataFormat *data, int nbBytes)
 
     int nbSamples = nbBytes / sizeof(SFLDataFormat); 
     for (int i = 0; i < nbSamples; i++) {
-
+        _debug("i: %d", i);
         _x = data[i];
 
         _y = (SFLDataFormat) ( (float) _x - (float) _xm1 + 0.9999 * (float) _ym1);
@@ -89,6 +89,22 @@ void DcBlocker::process (SFLDataFormat *data, int nbBytes)
     }
 }
 
-int DcBlocker::process(SFLDataFormat *inputData, SFLDataFormat *outputData, int nbBytes) { return 0;}
+int DcBlocker::process(SFLDataFormat *inputData, SFLDataFormat *outputData, int nbBytes) { 
+
+  int nbSamples = nbBytes / sizeof(SFLDataFormat); 
+    for (int i = 0; i < nbSamples; i++) {
+
+        _x = inputData[i];
+
+        _y = (SFLDataFormat) ( (float) _x - (float) _xm1 + 0.9999 * (float) _ym1);
+        _xm1 = _x;
+        _ym1 = _y;
+
+        outputData[i] = _y;
+    }
+
+  return 0;
+
+}
 
 void DcBlocker::process(SFLDataFormat *micData, SFLDataFormat *spkrData, SFLDataFormat *outputData, int nbBytes) {}

sflphone-common/src/audio/pulseaudio/pulselayer.cpp

@@ -981,11 +981,18 @@ void PulseLayer::readFromMic (void)
 
         } else {
 
+	    SFLDataFormat* filter_out = (SFLDataFormat*) pa_xmalloc (r);
+
+	    // remove dc offset
+            _audiofilter->processAudio((SFLDataFormat *)data, filter_out, r);
+
 	    // echo cancellation processing
-	  int sampleready = _echoCanceller->processAudio((SFLDataFormat *)data, echoCancelledMic, r);
+	    int sampleready = _echoCanceller->processAudio((SFLDataFormat *)data, echoCancelledMic, r);
 
             // no resampling required
             getMainBuffer()->putData (echoCancelledMic, sampleready*sizeof (SFLDataFormat), 100);
+
+	    pa_xfree(filter_out);
         }