📄 ns127.c
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/**********************************************************************
Each of the companies; Lucent, Motorola, Nokia, and Qualcomm (hereinafter
referred to individually as "Source" or collectively as "Sources") do
hereby state:
To the extent to which the Source(s) may legally and freely do so, the
Source(s), upon submission of a Contribution, grant(s) a free,
irrevocable, non-exclusive, license to the Third Generation Partnership
Project 2 (3GPP2) and its Organizational Partners: ARIB, CCSA, TIA, TTA,
and TTC, under the Source's copyright or copyright license rights in the
Contribution, to, in whole or in part, copy, make derivative works,
perform, display and distribute the Contribution and derivative works
thereof consistent with 3GPP2's and each Organizational Partner's
policies and procedures, with the right to (i) sublicense the foregoing
rights consistent with 3GPP2's and each Organizational Partner's policies
and procedures and (ii) copyright and sell, if applicable) in 3GPP2's name
or each Organizational Partner's name any 3GPP2 or transposed Publication
even though this Publication may contain the Contribution or a derivative
work thereof. The Contribution shall disclose any known limitations on
the Source's rights to license as herein provided.
When a Contribution is submitted by the Source(s) to assist the
formulating groups of 3GPP2 or any of its Organizational Partners, it
is proposed to the Committee as a basis for discussion and is not to
be construed as a binding proposal on the Source(s). The Source(s)
specifically reserve(s) the right to amend or modify the material
contained in the Contribution. Nothing contained in the Contribution
shall, except as herein expressly provided, be construed as conferring
by implication, estoppel or otherwise, any license or right under (i)
any existing or later issuing patent, whether or not the use of
information in the document necessarily employs an invention of any
existing or later issued patent, (ii) any copyright, (iii) any
trademark, or (iv) any other intellectual property right.
With respect to the Software necessary for the practice of any or
all Normative portions of the Enhanced Variable Rate Codec (EVRC) as
it exists on the date of submittal of this form, should the EVRC be
approved as a Specification or Report by 3GPP2, or as a transposed
Standard by any of the 3GPP2's Organizational Partners, the Source(s)
state(s) that a worldwide license to reproduce, use and distribute the
Software, the license rights to which are held by the Source(s), will
be made available to applicants under terms and conditions that are
reasonable and non-discriminatory, which may include monetary compensation,
and only to the extent necessary for the practice of any or all of the
Normative portions of the EVRC or the field of use of practice of the
EVRC Specification, Report, or Standard. The statement contained above
is irrevocable and shall be binding upon the Source(s). In the event
the rights of the Source(s) in and to copyright or copyright license
rights subject to such commitment are assigned or transferred, the
Source(s) shall notify the assignee or transferee of the existence of
such commitments.
*******************************************************************/
/*======================================================================*/
/* Enhanced Variable Rate Codec - Bit-Exact C Specification */
/* Copyright (C) 1997-1998 Telecommunications Industry Association. */
/* All rights reserved. */
/*----------------------------------------------------------------------*/
/* Note: Reproduction and use of this software for the design and */
/* development of North American Wideband CDMA Digital */
/* Cellular Telephony Standards is authorized by the TIA. */
/* The TIA does not authorize the use of this software for any */
/* other purpose. */
/* */
/* The availability of this software does not provide any license */
/* by implication, estoppel, or otherwise under any patent rights */
/* of TIA member companies or others covering any use of the */
/* contents herein. */
/* */
/* Any copies of this software or derivative works must include */
/* this and all other proprietary notices. */
/*======================================================================*/
/* ns127.c */
/*****************************************************************
*
* EVRC Noise Suppression
*
* Input: The input to the function is a Shortword pointer to the
* array of data to be noise suppressed.
*
* Output: There is no return value. The input array is replaced
* with the noise suppressed values.
*
*
* Written by: Tenkasi V. Ramabadran
* Date: December 28, 1994
*
* Last Modified: James Ashley
* Date: November 7, 1996
*
* Version Date Description
*
* 1.0 12/01/95 Released to TIA TR45.5.1.1
* 1.1 02/14/96 Init Noise to first 4 frames
* 1.2 02/19/96 Bug fix in frame_cnt declaration
* 03/27/96 Revised for Fixed Point Calculations
* 05/28/96 Adjust thresholds for -6 dB input level,
* add block_norm/denorm around FFT/IFFT,
* general scaling cleanup.
* 1.3 08/09/96 Adjusted thresholds to 0dB input level,
* Modified block_denormalization to provide 6 db adjustment.
* 1.4 10/15/96 Apply block_norm call to farray_ptr instead of data_buffer
* (fixes high level input problems). (JPA)
* 1.5 11/07/96 Fix bug in block_norm(). (JPA)
*****************************************************************/
#include <stdio.h>
/* Includes */
#include "mathevrc.h"
#include "mathdp31.h"
#include "mathadv.h"
/* Defines */
#define FRM_LEN 80
#define DELAY 24
#define FFT_LEN 128
#define NUM_CHAN 16
#define LO_CHAN 0
#define MID_CHAN 5
#define HI_CHAN 15
#define TRUE 1
#define FALSE 0
#define UPDATE_THLD 35
#define METRIC_THLD 45
#define INDEX_THLD 12
#define SETBACK_THLD 12
#define SNR_THLD 6
#define INDEX_CNT_THLD 5
#define HYSTER_CNT_THLD 6
#define UPDATE_CNT_THLD 50
/* Define the following if 0db input to ns */
#define INPUT_0_DB
#ifdef INPUT_MINUS_6_DB
#define NOISE_FLOOR_CHAN 64 /* 1.0/4 scaled as 23,8 */
#define MIN_CHAN_ENRG 4 /* 0.0625/4 scaled as 23,8 */
#define MIN_NOISE_ENRG 4 /* 0.0625/4 scaled as 23,8 */
#define INE_CHAN 1024 /* 16.0/4 scaled as 23,8 */
#define INE_NOISE 1024 /* 16.0/4 scaled as 23,8 */
#define HIGH_TCE_DB 1408 /* 44.0 scaled as 10,5 */
#define LOW_TCE_DB 768 /* 24.0 scaled as 10,5 */
#endif
#ifdef INPUT_0_DB
#define NOISE_FLOOR_CHAN 256 /* 1.0 scaled as 23,8 */
#define MIN_CHAN_ENRG 16 /* 0.0625 scaled as 23,8 */
#define MIN_NOISE_ENRG 16 /* 0.0625 scaled as 23,8 */
#define INE_CHAN 4096 /* 16.0 scaled as 23,8 */
#define INE_NOISE 4096 /* 16.0 scaled as 23,8 */
#define HIGH_TCE_DB 1600 /* 50.0 scaled as 10,5 */
#define LOW_TCE_DB 960 /* 30.0 scaled as 10,5 */
#endif
#define TCE_RANGE (HIGH_TCE_DB - LOW_TCE_DB)
#define HIGH_ALPHA_S5_10 1023
#define LOW_ALPHA_S5_10 511
#define HIGH_ALPHA 32440 /* 0.99 scaled as 0,15 */
#define LOW_ALPHA 16383 /* 0.50 scaled as 0,15 */
#define ALPHA_RANGE (HIGH_ALPHA - LOW_ALPHA)
#define ALPHA_RAN_DIV_TCE_RAN 803 /* (0.99 - 0.50) / 20 scaled as 0,15 */
#define DEV_THLD 896 /* 28.0 scaled as 10,5 */
#define PRE_EMP_FAC -26214 /* -0.8 scaled as 0,15 */
#define CEE_SM_FAC 1181116006 /* 0.55 scaled as 0,31 */
#define ONE_MINUS_CEE_SM_FAC 966367642 /* 0.55 scaled as 0,31 */
#define MIN_GAIN -27262976 /* (-13.0) scaled as 11,20 */
#define GAIN_SLOPE 14879 /* 0.45 scaled as 0,15 */
#define CNE_SM_FAC 3277 /* 0.1 scaled as 0,15 */
#define ONE_MINUS_CNE_SM_FAC (32767-CNE_SM_FAC)
#define DE_EMP_FAC 26214 /* 0.8 scaled as 0,15 */
#define LOG_OFFSET 626255212 /* 9.3319 scaled as 5,26 */
#define ONE_OVER_20 1638 /* 1/20 scaled as 0,15 */
#define TEN_S5_10 10270 /* 10.0 scaled as 5,10 */
#define CONST_0_1875_S10_21 393216 /* 0.1875 scaled as 10,21 */
#define CONST_2_667_S5_10 2731 /* 2.667 scaled as 5,10 */
#define FFT_HEADROOM 2
#define IFFT_HEADROOM 4
/* Local functions */
Shortword block_norm(Shortword * data, Shortword size, Shortword headroom)
{
Shortword i, max, scnt, adata;
max = abs(data[0]);
for (i = 1; i < size; i++)
{
adata = abs(data[i]);
if (adata > max)
max = adata;
}
scnt = norm_s(max) - headroom;
for (i = 0; i < size; i++)
{
data[i] = shift_r(data[i], scnt);
}
return (scnt);
}
void block_denorm(Shortword * data, Shortword size, Shortword scnt)
{
Shortword i;
for (i = 0; i < size; i++)
{
data[i] = shift_r(data[i], negate(scnt));
}
return;
}
/* The noise supression function */
void noise_suprs(Shortword * farray_ptr)
{
/*
* The channel table is defined below. In this table, the
* lower and higher frequency coefficients for each of the 16
* channels are specified. The table excludes the coefficients
* with numbers 0 (DC), 1, and 64 (Foldover frequency). For
* these coefficients, the gain is always set at 1.0 (0 dB).
*/
static Shortword ch_tbl[NUM_CHAN][2] =
{
{2, 3},
{4, 5},
{6, 7},
{8, 9},
{10, 11},
{12, 13},
{14, 16},
{17, 19},
{20, 22},
{23, 26},
{27, 30},
{31, 35},
{36, 41},
{42, 48},
{49, 55},
{56, 63}
};
static Shortword ch_tbl_sh[NUM_CHAN][2] =
{
{TRUE, 1},
{TRUE, 1},
{TRUE, 1},
{TRUE, 1},
{TRUE, 1},
{TRUE, 1},
{FALSE, 10922},
{FALSE, 10922},
{FALSE, 10922},
{TRUE, 2},
{TRUE, 2},
{FALSE, 6553},
{FALSE, 5462},
{FALSE, 4681},
{FALSE, 4681},
{TRUE, 3}
};
/*
* The voice metric table is defined below. It is a non-
* linear table with a deadband near zero. It maps the SNR
* index (quantized SNR value) to a number that is a measure
* of voice quality.
*/
static int vm_tbl[90] =
{
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 7, 7, 7,
8, 8, 9, 9, 10, 10, 11, 12, 12, 13, 13, 14, 15,
15, 16, 17, 17, 18, 19, 20, 20, 21, 22, 23, 24,
24, 25, 26, 27, 28, 28, 29, 30, 31, 32, 33, 34,
35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45,
46, 47, 48, 49, 50, 50, 50, 50, 50, 50, 50, 50,
50, 50
};
static Shortword window[DELAY + FRM_LEN] =
{
35, 315, 869, 1690, 2761, 4066, 5581, 7281, 9137,
11117, 13187, 15312, 17455, 19580, 21650, 23630,
25486, 27186, 28701, 30006, 31077, 31898, 32452,
32732, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32767, 32767, 32767, 32767, 32767, 32767,
32767, 32732, 32452, 31898, 31077, 30006, 28701,
27186, 25486, 23630, 21650, 19580, 17455, 15312,
13187, 11117, 9137, 7281, 5581, 4066, 2761, 1690,
869, 315, 35
};
static Shortword first = TRUE;
static Shortword pre_emp_mem;
static Shortword de_emp_mem;
static Shortword overlap[FFT_LEN - FRM_LEN];
static Shortword ch_gain[FFT_LEN / 2]; /* scaled as 0,15 */
static Shortword update_cnt;
static Shortword window_overlap[DELAY];
static Shortword hyster_cnt;
static Shortword last_update_cnt;
static Shortword ch_enrg_long_db[NUM_CHAN]; /* scaled as 10,5 */
static Longword frame_cnt;
static Longword ch_enrg[NUM_CHAN]; /* scaled as 23,8 */
static Longword ch_noise[NUM_CHAN]; /* scaled as 15,16 (change to 23,8) */
static Shortword last_normb_shift; /* last block norm shift count */
Longword enrg; /* scaled as 30,1 */
Longword tne; /* scaled as 15,16 (change to 23,8) */
Longword tce; /* scaled as 23,8 */
Longword gain; /* scaled as 11,20 */
Shortword data_buffer[FFT_LEN];
Shortword ch_snr[NUM_CHAN]; /* scaled as 15,0 */
Shortword ftmp2; /* scaled as 0,15 */
Shortword vm_sum; /* scaled as 15,0 */
Shortword ch_enrg_dev; /* scaled as 10,5 */
Shortword ch_enrg_db[NUM_CHAN]; /* scaled as 10,5 */
Shortword alpha; /* scaled as 0,15 */
int i, j, j1, j2;
int update_flag, modify_flag, index_cnt;
Longword Ltmp, Ltmp1, Ltmp2, Ltmp3;
Shortword tmp, tmp1, tmp2, norm_shift, norm_shift1;
Shortword normb_shift; /* block norm shift count */
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