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Different bark formula

--- a/encoder.c

+++ b/encoder.c

@@ -375,7 +375,7 @@

   faacv->DLLMinorVersion = 30;

   faacv->MajorVersion = 0;

   faacv->MinorVersion = 70;

-  strcpy(faacv->HomePage, "http://www.slimline.net/aac/");

+  strcpy(faacv->HomePage, "http://faac.sourceforge.net/");

   return faacv;

 }

--- a/psych.c

+++ b/psych.c

@@ -223,7 +223,7 @@

     double hz;

     if(bark>2.0)

-	hz = 1960 * (bark + 0.53) / (26.28 - bark);

+	hz = 1960 / (26.81 / (bark + 0.53) - 1);

     else

 	hz = bark * 102.9;

@@ -241,7 +241,7 @@

     double bark;

     if(hz>200.0)

-	bark = 26.81 * hz / (1960 + hz) - 0.53; 

+	bark = 26.81 / (1 + (1960 / hz)) - 0.53; 

     else

 	bark = hz / 102.9;

@@ -254,9 +254,9 @@

 						 PARTITION_TABLE_SHORT *part_tbl_short

 						 )

 {

-    int b,bb; /* Jul 10 */

+    int b,bb;

     double tmp;

-	int partition[1024], j, w;

+	int j;

 	int cbands, prev_cbound, crit_bands, cbound;

 	cbands = (int)hz2bark(sampling_rate/2.0) + 1;

@@ -308,29 +308,20 @@

 	part_tbl_short->len = crit_bands+1;

 //	printf("%d %d\n",part_tbl_short->len, part_tbl_short->w_high[crit_bands]);

-	for (b = 0; b < part_tbl_long->len; b++) {

-		for(w = part_tbl_long->w_low[b]; w <= part_tbl_long->w_high[b]; ++w){

-			partition[w] = b;

-		}

-	}

-	for(b = 0; b < part_tbl_long->len ; b++) {

+	// Using Traunmuller formula for bark, for more info see:

+	// http://www.ling.su.se/staff/hartmut/bark.htm

+	for(b = 0; b < part_tbl_long->len; b++) {

 		double ji = part_tbl_long->w_low[b] + (part_tbl_long->width[b]-1)/2.0;

 		double freq = part_tbl_long->sampling_rate*ji/2048;

-		double bark = 13*atan(0.00076*freq)+3.5*atan((freq/7500)*(freq/7500));

+		double bark = 26.81/(1+(1960/freq)) - 0.53;

 		dyn_long.bval[b] = bark;

 	}

-	for (b = 0; b < part_tbl_short->len; b++) {

-		for(w = part_tbl_short->w_low[b]; w <= part_tbl_short->w_high[b]; ++w){

-			partition[w] = b;

-		}

-	}

-

 	for(b = 0; b < part_tbl_short->len ; b++) {

 		double ji = part_tbl_short->w_low[b] + (part_tbl_short->width[b]-1)/2.0;

 		double freq = part_tbl_short->sampling_rate*ji/256;

-		double bark = 13*atan(0.00076*freq) + 3.5*atan((freq/7500)*(freq/7500));

+		double bark = 26.81/(1+(1960/freq)) - 0.53;

 		dyn_short.bval[b]=bark;

 	}