Reformat FIR Filter spacing

filter_fir.cpp

@@ -22,54 +22,57 @@
 
 #include "filter_fir.h"
 
-void AudioFilterFIR::begin(short *cp,int n_coeffs)
+void AudioFilterFIR::begin(short *cp, int n_coeffs)
 {
-  // pointer to coefficients
-  coeff_p = cp;
-  // Initialize FIR instances for the left and right channels
-  if(coeff_p && (coeff_p != FIR_PASSTHRU)) {
-    arm_fir_init_q15(&l_fir_inst, n_coeffs, coeff_p, &l_StateQ15[0], AUDIO_BLOCK_SAMPLES);
-  }
+	// pointer to coefficients
+	coeff_p = cp;
+	// Initialize FIR instances for the left and right channels
+	if(coeff_p && (coeff_p != FIR_PASSTHRU)) {
+		arm_fir_init_q15(&l_fir_inst, n_coeffs, coeff_p,
+			&l_StateQ15[0], AUDIO_BLOCK_SAMPLES);
+	}
 }
 
 // This has the same effect as begin(NULL,0);
 void AudioFilterFIR::stop(void)
 {
-  coeff_p = NULL;
+	coeff_p = NULL;
 }
 
 
 void AudioFilterFIR::update(void)
 {
-  audio_block_t *block,*b_new;
+	audio_block_t *block,*b_new;
   
-  // If there's no coefficient table, give up.  
-  if(coeff_p == NULL)return;
+	// If there's no coefficient table, give up.  
+	if(coeff_p == NULL) return;
 
-  // do passthru
-  if(coeff_p == FIR_PASSTHRU) {
-    // Just passthrough
-    block = receiveReadOnly(0);
-    if(block) {
-      transmit(block,0);
-      release(block);
-    }
-    return;
-  }
-  // Left Channel
-  block = receiveReadOnly(0);
-  // get a block for the FIR output
-  b_new = allocate();
-  if(block && b_new) {
-    if(arm_fast)
-    	arm_fir_fast_q15(&l_fir_inst, (q15_t *)block->data, (q15_t *)b_new->data, AUDIO_BLOCK_SAMPLES);
-    else
-    	arm_fir_q15(&l_fir_inst, (q15_t *)block->data, (q15_t *)b_new->data, AUDIO_BLOCK_SAMPLES); 
-    // send the FIR output to the left channel
-    transmit(b_new,0);
-  }
-  if(block)release(block);
-  if(b_new)release(b_new);
+	// do passthru
+	if (coeff_p == FIR_PASSTHRU) {
+		// Just passthrough
+		block = receiveReadOnly(0);
+		if(block) {
+			transmit(block,0);
+			release(block);
+		}
+		return;
+	}
+	// Left Channel
+	block = receiveReadOnly(0);
+	// get a block for the FIR output
+	b_new = allocate();
+	if (block && b_new) {
+		if (arm_fast) {
+			arm_fir_fast_q15(&l_fir_inst, (q15_t *)block->data,
+				(q15_t *)b_new->data, AUDIO_BLOCK_SAMPLES);
+		} else {
+			arm_fir_q15(&l_fir_inst, (q15_t *)block->data,
+				(q15_t *)b_new->data, AUDIO_BLOCK_SAMPLES);
+		}
+		transmit(b_new,0); // send the FIR output
+	}
+	if (block) release(block);
+	if (b_new) release(b_new);
 }
 
 

filter_fir.h

@@ -26,45 +26,34 @@
 #include "AudioStream.h"
 #include "arm_math.h"
 
-#define USE_FAST_FIR true
-#define USE_SLOW_FIR false
-
-
-// Maximum number of coefficients in a FIR filter
-// The audio breaks up with 128 coefficients so a
-// maximum of 150 is more than sufficient
-#define MAX_COEFFS 150
-
 // Indicates that the code should just pass through the audio
 // without any filtering (as opposed to doing nothing at all)
 #define FIR_PASSTHRU ((short *) 1)
 
-class AudioFilterFIR : 
-public AudioStream
+#define FIR_MAX_COEFFS 120
+
+class AudioFilterFIR : public AudioStream
 {
 public:
-  AudioFilterFIR(const boolean a_f): 
-  AudioStream(1,inputQueueArray), arm_fast(a_f), coeff_p(NULL)
-  { 
-  }
-
-  void begin(short *coeff_p,int n_coeffs);
-  virtual void update(void);
-  void stop(void);
+	AudioFilterFIR(const boolean a_f): AudioStream(1,inputQueueArray),
+	  arm_fast(a_f), coeff_p(NULL) { 
+	}
+	void begin(short *coeff_p,int n_coeffs);
+	virtual void update(void);
+	void stop(void);
   
 private:
-  audio_block_t *inputQueueArray[1];
-  // arm state arrays and FIR instances for left and right channels
-  // the state arrays are defined to handle a maximum of MAX_COEFFS
-  // coefficients in a filter
-  q15_t l_StateQ15[AUDIO_BLOCK_SAMPLES + MAX_COEFFS];
-
-  // Whether to use the fast arm FIR code 
-  const boolean arm_fast;
-  // pointer to current coefficients or NULL or FIR_PASSTHRU
-  short *coeff_p;
-  arm_fir_instance_q15 l_fir_inst;
-
+	audio_block_t *inputQueueArray[1];
+	// arm state arrays and FIR instances for left and right channels
+	// the state arrays are defined to handle a maximum of MAX_COEFFS
+	// coefficients in a filter
+	q15_t l_StateQ15[AUDIO_BLOCK_SAMPLES + FIR_MAX_COEFFS];
+
+	// Whether to use the fast arm FIR code 
+	const boolean arm_fast;
+	// pointer to current coefficients or NULL or FIR_PASSTHRU
+	short *coeff_p;
+	arm_fir_instance_q15 l_fir_inst;
 };
 
 #endif