Merge pull request #11 from robsoles/master

fix for compounding/cascading filters

filter_biquad.cpp

@@ -34,7 +34,6 @@ void AudioFilterBiquad::update(void)
 	uint32_t in2, out2, aprev, bprev, flag;
 	uint32_t *data, *end;
 	int32_t *state;
-
 	block = receiveWritable();
 	if (!block) return;
 	data = (uint32_t *)(block->data);
@@ -73,19 +72,26 @@ void AudioFilterBiquad::update(void)
 		*state++ = sum | flag;
 		*(state-2) = bprev;
 		*(state-3) = aprev;
+		data = (uint32_t *)(block->data); // needs to be reset, may as well be done here
 	} while (flag);
 	transmit(block);
 	release(block);
 }
 
-void AudioFilterBiquad::updateCoefs(int *source, bool doReset)
+void AudioFilterBiquad::updateCoefs(uint8_t set,int *source, bool doReset)
 {
 	int32_t *dest=(int32_t *)definition;
-	int32_t *src=(int32_t *)source;
+	while(set)
+	{
+		*dest+=7;
+		if(!(*dest&0x80000000)) return;
+		*dest++;
+		set--;
+	}
 	__disable_irq();
 	for(uint8_t index=0;index<5;index++)
 	{
-		*dest++=*src++;
+		*dest++=*source++;
 	}
 	if(doReset)
 	{
@@ -96,8 +102,3 @@ void AudioFilterBiquad::updateCoefs(int *source, bool doReset)
 	__enable_irq();
 }
 
-void AudioFilterBiquad::updateCoefs(int *source)
-{
-	updateCoefs(source,false);
-}
-

filter_biquad.h

@@ -36,8 +36,11 @@ public:
 	   : AudioStream(1, inputQueueArray), definition(parameters) { }
 	virtual void update(void);
 	
-	void updateCoefs(int *source, bool doReset);
-	void updateCoefs(int *source);
+	void updateCoefs(uint8_t set,int *source, bool doReset);
+
+	void updateCoefs(uint8_t set,int *source) { updateCoefs(set,source,false); }
+	void updateCoefs(int *source, bool doReset) { updateCoefs(0,source,doReset); }
+	void updateCoefs(int *source) { updateCoefs(0,source,false); }
 private:
 	int *definition;
 	audio_block_t *inputQueueArray[1];