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Diffstat (limited to 'drivers/dahdi/kb1ec_const.h')
| -rw-r--r-- | drivers/dahdi/kb1ec_const.h | 72 |
1 files changed, 0 insertions, 72 deletions
diff --git a/drivers/dahdi/kb1ec_const.h b/drivers/dahdi/kb1ec_const.h deleted file mode 100644 index 0849b14..0000000 --- a/drivers/dahdi/kb1ec_const.h +++ /dev/null @@ -1,72 +0,0 @@ -/* - Important constants for tuning kb1 echo can - */ -#ifndef _MEC2_CONST_H -#define _MEC2_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 */ - - -/***************************************************************/ -/* 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 /* _MEC2_CONST_H */ - |