Merged FFT into Graphic Equalizer.

1 files changed, 40 insertions, 53 deletions

diff --git a/Graphic_Equalizer/src/fft.hcc b/Graphic_Equalizer/src/fft.hcc
index 7c3fa94..92468a8 100644
--- a/Graphic_Equalizer/src/fft.hcc
+++ b/Graphic_Equalizer/src/fft.hcc
@@ -1,13 +1,12 @@
-#include <pal_master.hch>

 #include <stdlib.hch>

-#include "weights256.hch"

-#include "config.hch"

+#include "pal_master.hch"

+

+#include "audio.hch"

+#include "weights_256.hch"

+#include "configuration.hch"

 #include "debug.hch"

 #include "xilinxmult.hch"

 

-#define      	PERFORM_FFT_CALCULATION 1

-#define		USE_UNSIGNED_AUDIO 0

-#define		PRINT_DEBUG 0

 /* Define two multi-port RAMs for FFT calculation; one for real and one for imaginary values

  * Extra block RAM settings are defined to make sure read and write actions can be performed

  * within one clock-cycle.

@@ -60,24 +59,10 @@ macro proc multiply(result, op_a, op_b)
 #if HARDWARE_MULTIPLY

 	xilinxmult(result, op_a, adjs(op_b,18));

 #else

-	macro expr mul_width  = (width(op_a) + width(op_b));

-	result = adjs(op_a, mul_width) * adjs(op_b, mul_width);

+	result = (adjs(op_a,38))*(adjs(op_a,38));

 #endif	

-/*	signed result;

-  	

-	fixed_mul(result,x,y);

-  	return result;*/

-}

-/*macro proc multiply(result, x,y) 

-{

-#if HARDWARE_MULTIPLY	

-	xilinxmult(result, adjs(x,18), adjs(y,18));

-#else	

-	result = ((adjs(x,36))*(adjs(y,36)));

-#endif

-  

 }

-*/

+

 

 

 

@@ -105,12 +90,21 @@ void calculate_fft(unsigned 1 select_inverse)
 #endif

   signed a,b;

 

+#if HARDWARE_MULTIPLY

+  // Macro to provide rescaling of 36-bit result of fixed point multiply

+  // down to an 18-bit result. The range of bits selected depends on the 

+  // number that represents the value of "1" in the trig function lookup

+  // tables. (Eg. for 16384 == 1, the lowest bit selected should be [14]).

   macro expr rescale (x) = (x[35] @ x[30:14]);

+#else

+  //Macro to rescale the multiply result down to a 24-bit value.

+  macro expr rescale (x) = ((x>>FRACBITS)<-24);

+#endif

 

   for(level=1;level<=NUMBER_OF_COLUMNS;level++) // count all the columns

   {

     	e=1<<(NUMBER_OF_COLUMNS-level+1); // number of points in each block in this column

-    	f=(e>>1)<-8; 					  // number of butterflies in each block in this column

+    	f=(e>>1)<-8; 			  // number of butterflies in each block in this column

 

     	for(j=1;j<=f;j++) 	// count all the butterflies in each block

     	{

@@ -281,9 +275,9 @@ void perform_fft(signed 16 *pcm_audio)
 

 /********************************************************************/

 #if HARDWARE_MULTIPLY

-void perform_ifft(signed 18 *modified_audio/*, unsigned 6 *ifft_info*/)

+void perform_ifft(signed 18 *modified_audio, signed 6 *ifft_info)

 #else

-void perform_ifft(signed 16 *modified_audio/*, unsigned 6 *ifft_info*/)

+void perform_ifft(signed 16 *modified_audio, signed 6 *ifft_info)

 #endif

 {

   	unsigned 6 k;

@@ -330,51 +324,48 @@ void perform_ifft(signed 16 *modified_audio/*, unsigned 6 *ifft_info*/)
 #else

 			modified_audio[k] = (p<-16);

 #endif

-			//ifft_info[k] = (unsigned)(p[15:10]); 		

+			ifft_info[k] = (p[17:12]);		

 			k++;

 		}

     	} while(k);

 }

 

 /********************************************************************/

-void equalize_audio(unsigned 4 *eq_level, unsigned 7 *fft_info)

+void equalize_audio(audiodata_t *audiodata)

 {

-#if 1

 #if HARDWARE_MULTIPLY

   signed 18 p,q;

 #else

   signed 24 p,q;

 #endif

-  signed 16 a;

+  signed 18 a;

   unsigned 8 i, mirror_i, bit, m, n;

   unsigned 7 old_value;

   unsigned 9 tmp;

   

   //macro expr equalize_bar = multiply(q,a)[29:6];

   

-  macro proc equalize_bar(result)

+  macro proc equalize_bar(retval)

   {

   	 signed result;

  	 multiply(result, q,a);

 #if HARDWARE_MULTIPLY

-	 result = result[29:12];

+	 retval = result[23:6]; //drop last 6 bit to compensate the maximum multiplication with 64 from the eq_settings array

 #else

-	 result = result[29:6];

+	 retval = result[29:6]; //drop last 6 bit to compensate the maximum multiplication with 64 from the eq_settings array

 #endif

   } 

-#if HARDWARE_MULTIPLY

-  p = real.read[0] - 10;

-#else

+

   p = real.read[0] - DC_COMPONENT; // remove DC component for calculations

-#endif

   real.rwrite[0] = p;

 //  imaginary.rwrite[0] = 0; 				   		// remove DC component 

 

   

-  for(i=0;i<=NUMBER_OF_FREQUENCIES;i++)	  

+  for(i=0;i!=NUMBER_OF_FREQUENCIES;i++)	  

   {  

-	// set multiplication factor (0..64) for current frequency bar

-	a = adjs(eq_settings[eq_level[i<-7]],16);

+	// set multiplication factor (0..64) for current frequency bar, The first frequency band must be equalized at 100% (63) since there is no DC-component taken into account.

+	a = (i==0) ? 63 : adjs(eq_settings[audiodata->equalizer_levels.write[0 @ (i <- 7)]],18);

+

 

 	// multiply frequency with this factor and divide by 64 (drop 6 LSB's)

 	q = real.read[i];

@@ -409,46 +400,42 @@ void equalize_audio(unsigned 4 *eq_level, unsigned 7 *fft_info)
     	if (p[17] == 1) p = -p; else delay;

 	if (q[17] == 1) q = -q; else delay;

 #else

-    	if (p[17] == 1) p = -p; else delay;

-	if (q[17] == 1) q = -q; else delay;

+    	if (p[23] == 1) p = -p; else delay;

+	if (q[23] == 1) q = -q; else delay;

 #endif

 	p = (p<q) ? q : p; // This is done to get the best visual frequency result

 	 

-	if (display_log)

+	if (audiodata->display_log)

 	{

 

 		bit=126;

 #if HARDWARE_MULTIPLY

 		while ((p[15] == 0) && (bit != 0))

 #else

-		while ((p[15] == 0) && (bit != 0))

+		while ((p[21] == 0) && (bit != 0))

 #endif

 			par

 			{

 				p = p<<1;

 				bit = bit - 18;

 			}

-		old_value = fft_info[i<-7];

+		old_value = audiodata->fft_info.write[0 @ (i <- 7)];

 		tmp = ((0@old_value) + (0@bit))>>1;

-		fft_info[i<-7] = (old_value <= (tmp<-7)) ? (tmp<-7) : old_value-1;

+		audiodata->fft_info.write[0 @ (i <- 7)] = (old_value <= (tmp<-7)) ? (tmp<-7) : old_value-1;

 	} 

 	else 

 	{

-		old_value = fft_info[i<-7];

+		old_value = audiodata->fft_info.write[0 @ (i <- 7)];

 #if HARDWARE_MULTIPLY

-		fft_info[i<-7] = (old_value<=(unsigned)(p[15:9])) ? (unsigned)(p[15:9]) : old_value-1;

+		audiodata->fft_info.write[0 @ (i <- 7)] = (old_value<=(unsigned)(p[15:9])) ? (unsigned)(p[15:9]) : old_value-1;

 #else

-		fft_info[i<-7] = (old_value<=(unsigned)(p[21:15])) ? (unsigned)(p[21:15]) : old_value-1;

+		audiodata->fft_info.write[0 @ (i <- 7)] = (old_value<=(unsigned)(p[21:15])) ? (unsigned)(p[21:15]) : old_value-1;

 #endif

 	}

   }

 

   // add DC component again before inverse FFT calculation is performed

-#if HARDWARE_MULTIPLY

-  p = real.read[0] +10;// + DC_COMPONENT; 

-#else

+

   p = real.read[0] + DC_COMPONENT; 

-#endif

   real.rwrite[0] = p;

-#endif

 }