Version 0.1.6 from FTP

git-svn-id: http://svn.digium.com/svn/zaptel/trunk@51 5390a7c7-147a-4af0-8ec9-7488f05a26cb

1 files changed, 9 insertions, 7 deletions

diff --git a/mec.h b/mec.h
index 779d949..3148ee9 100755
--- a/mec.h
+++ b/mec.h
@@ -23,15 +23,17 @@
 #ifndef _MEC_H
 #define _MEC_H 
 
-#define NUM_TAPS 64 /* Must be power of two */
+/* You have to express the size of the echo canceller in taps as
+   a power of 2 (6 = 64 taps, 7 = 128 taps, 8 = 256 taps) */
+#define	NUM_TAPS_POW2	6	/* Size of echo canceller in power of 2 (taps) */
+#define NUM_TAPS (1 << NUM_TAPS_POW2) /* Actual number of taps */
 #define TAP_MASK (NUM_TAPS-1)
 
 
-
-#define SIGMA_LU_POW 6
-#define SIGMA_LY_POW 6
-#define SIGMA_YT_POW 5
-#define SIGMA_ST_POW 5
+#define SIGMA_LU_POW NUM_TAPS_POW2
+#define SIGMA_LY_POW NUM_TAPS_POW2
+#define SIGMA_YT_POW (NUM_TAPS_POW2 - 1)
+#define SIGMA_ST_POW (NUM_TAPS_POW2 - 1)
 
 #define BETA_POW	  8
 
@@ -142,7 +144,7 @@ static INLINE short process_cc(mark_ec *ec, short tx, short txabs, short rx, sho
 		pos = (pos - 1) & TAP_MASK;
 	}
 	
-	r_hat >>= 18;
+	r_hat >>= 16;
 	
 	if (ec->hangt > 0)
 		ec->hangt--;