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diff --git a/mg2ec_const.h b/mg2ec_const.h
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+/* 
+   Important constants for tuning mg2 echo can
+ */
+#ifndef _MG2_CONST_H
+#define _MG2_CONST_H
+
+
+/* Convergence (aka. adaptation) speed -- higher means slower */
+#define DEFAULT_BETA1_I 2048
+
+/* Constants for various power computations */
+#define DEFAULT_SIGMA_LY_I 7
+#define DEFAULT_SIGMA_LU_I 7
+#define DEFAULT_ALPHA_ST_I 5 		/* near-end speech detection sensitivity factor */
+#define DEFAULT_ALPHA_YT_I 5
+
+#define DEFAULT_CUTOFF_I 128
+
+/* Define the near-end speech hangover counter: if near-end speech 
+ *  is declared, hcntr is set equal to hangt (see pg. 432)
+ */
+#define DEFAULT_HANGT 600  		/* in samples, so 600 samples = 75ms */
+
+/* define the residual error suppression threshold */
+#define DEFAULT_SUPPR_I 16		/* 16 = -24db */
+
+/* This is the minimum reference signal power estimate level 
+ *  that will result in filter adaptation.
+ * If this is too low then background noise will cause the filter 
+ *  coefficients to constantly be updated.
+ */
+#define MIN_UPDATE_THRESH_I 4096
+
+/* The number of samples used to update coefficients using the
+ *  the block update method (M). It should be related back to the 
+ *  length of the echo can.
+ * ie. it only updates coefficients when (sample number MOD default_m) = 0
+ *
+ *  Getting this wrong may cause an oops. Consider yourself warned!
+ */
+#define DEFAULT_M 16		  	/* every 16th sample */
+
+/* If AGGRESSIVE supression is enabled, then we start cancelling residual 
+ * echos again even while there is potentially the very end of a near-side 
+ *  signal present.
+ * This defines how many samples of DEFAULT_HANGT can remain before we
+ *  kick back in
+ */
+#define AGGRESSIVE_HCNTR 160		/* in samples, so 160 samples = 20ms */
+
+/* This knob controls the number of passes the residual echo supression 
+ * algorithm makes.
+ */
+#ifdef AGGRESSIVE_SUPPRESSOR
+ #define RESIDUAL_SUPRESSION_PASSES 2
+#else
+ #define RESIDUAL_SUPRESSION_PASSES 1
+#endif
+
+
+/***************************************************************/
+/* The following knobs are not implemented in the current code */
+
+/* we need a dynamic level of suppression varying with the ratio of the 
+   power of the echo to the power of the reference signal this is 
+   done so that we have a  smoother background. 		
+   we have a higher suppression when the power ratio is closer to
+   suppr_ceil and reduces logarithmically as we approach suppr_floor.
+ */
+#define SUPPR_FLOOR -64
+#define SUPPR_CEIL -24
+
+/* in a second departure, we calculate the residual error suppression
+ * as a percentage of the reference signal energy level. The threshold
+ * is defined in terms of dB below the reference signal.
+ */
+#define RES_SUPR_FACTOR -20
+
+
+#endif /* _MG2_CONST_H */
+