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diff --git a/opencore/codecs_v2/audio/gsm_amr/amr_nb/dec/src/b_cn_cod.cpp b/opencore/codecs_v2/audio/gsm_amr/amr_nb/dec/src/b_cn_cod.cpp
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+/* ------------------------------------------------------------------
+ * Copyright (C) 1998-2009 PacketVideo
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ * -------------------------------------------------------------------
+ */
+/****************************************************************************************
+Portions of this file are derived from the following 3GPP standard:
+
+ 3GPP TS 26.073
+ ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
+ Available from http://www.3gpp.org
+
+(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC)
+Permission to distribute, modify and use this file under the standard license
+terms listed above has been obtained from the copyright holder.
+****************************************************************************************/
+/*
+------------------------------------------------------------------------------
+
+
+
+ Filename: b_cn_cod.cpp
+ Functions: pseudonoise
+ build_CN_code
+ build_CN_param
+
+------------------------------------------------------------------------------
+ MODULE DESCRIPTION
+
+ This module contains functions for comfort noise(CN) generation.
+
+------------------------------------------------------------------------------
+*/
+
+
+/*----------------------------------------------------------------------------
+; INCLUDES
+----------------------------------------------------------------------------*/
+#include "b_cn_cod.h"
+#include "basic_op.h"
+#include "cnst.h"
+
+/*----------------------------------------------------------------------------
+; MACROS
+; [Define module specific macros here]
+----------------------------------------------------------------------------*/
+
+
+/*----------------------------------------------------------------------------
+; DEFINES
+; [Include all pre-processor statements here. Include conditional
+; compile variables also.]
+----------------------------------------------------------------------------*/
+#define NB_PULSE 10 /* number of random pulses in DTX operation */
+
+/*----------------------------------------------------------------------------
+; LOCAL FUNCTION DEFINITIONS
+; [List function prototypes here]
+----------------------------------------------------------------------------*/
+
+/*----------------------------------------------------------------------------
+; LOCAL VARIABLE DEFINITIONS
+; [Variable declaration - defined here and used outside this module]
+----------------------------------------------------------------------------*/
+
+/*
+------------------------------------------------------------------------------
+ FUNCTION NAME: pseudonoise
+------------------------------------------------------------------------------
+ INPUT AND OUTPUT DEFINITIONS
+
+ Inputs:
+ pShift_reg = pointer to Old CN generator shift register state (Word32)
+ no_bits = Number of bits (Word16)
+
+ Outputs:
+ pShift_reg -> Updated CN generator shift register state
+
+ Returns:
+ noise_bits = Generated random integer value (Word16)
+
+ Global Variables Used:
+ None
+
+ Local Variables Needed:
+ None
+
+------------------------------------------------------------------------------
+ FUNCTION DESCRIPTION
+
+ Generate a random integer value to use in comfort noise generation. The
+ algorithm uses polynomial x^31 + x^3 + 1. Length of the PN sequence
+ is 2^31 - 1
+
+------------------------------------------------------------------------------
+ REQUIREMENTS
+
+ None
+
+------------------------------------------------------------------------------
+ REFERENCES
+
+ b_cn_cod.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001
+
+------------------------------------------------------------------------------
+ PSEUDO-CODE
+
+Word16 pseudonoise (
+ Word32 *shift_reg, // i/o : Old CN generator shift register state
+ Word16 no_bits // i : Number of bits
+)
+{
+ Word16 noise_bits, Sn, i;
+
+ noise_bits = 0;
+ for (i = 0; i < no_bits; i++)
+ {
+ // State n == 31
+ if ((*shift_reg & 0x00000001L) != 0)
+ {
+ Sn = 1;
+ }
+ else
+ {
+ Sn = 0;
+ }
+
+ // State n == 3
+ if ((*shift_reg & 0x10000000L) != 0)
+ {
+ Sn = Sn ^ 1;
+ }
+ else
+ {
+ Sn = Sn ^ 0;
+ }
+
+ noise_bits = shl (noise_bits, 1);
+ noise_bits = noise_bits | (extract_l (*shift_reg) & 1);
+
+ *shift_reg = L_shr (*shift_reg, 1);
+ if (Sn & 1)
+ {
+ *shift_reg = *shift_reg | 0x40000000L;
+ }
+ }
+ return noise_bits;
+}
+
+------------------------------------------------------------------------------
+ CAUTION [optional]
+ [State any special notes, constraints or cautions for users of this function]
+
+------------------------------------------------------------------------------
+*/
+
+/*----------------------------------------------------------------------------
+; FUNCTION CODE
+----------------------------------------------------------------------------*/
+
+Word16 pseudonoise(
+ Word32 *pShift_reg, /* i/o : Old CN generator shift register state */
+ Word16 no_bits /* i : Number of bits */
+)
+{
+ Word16 noise_bits;
+ Word16 Sn;
+ Word16 i;
+ Word16 temp;
+
+ noise_bits = 0;
+
+ for (i = 0; i < no_bits; i++)
+ {
+ /* State n == 31 */
+ if ((*pShift_reg & 0x00000001L) != 0)
+ {
+ Sn = 1;
+ }
+ else
+ {
+ Sn = 0;
+ }
+
+ /* State n == 3 */
+ if ((*pShift_reg & 0x10000000L) != 0)
+ {
+ Sn ^= 1;
+ }
+ else
+ {
+ Sn ^= 0;
+ }
+
+ noise_bits <<= 1;
+
+ temp = (Word16)((*pShift_reg) & 1);
+ noise_bits |= temp;
+
+ *pShift_reg >>= 1;
+ if (Sn & 1)
+ {
+ *pShift_reg |= 0x40000000L;
+ }
+ }
+ return noise_bits;
+}
+
+/*
+------------------------------------------------------------------------------
+ FUNCTION NAME: build_CN_code
+------------------------------------------------------------------------------
+ INPUT AND OUTPUT DEFINITIONS
+
+ Inputs:
+ pSeed = pointer to the Old CN generator shift register state (Word32)
+ cod[] = array to hold the generated CN fixed code vector (Word16)
+ pOverflow = pointer to overflow flag (Flag)
+
+ Outputs:
+ cod[] = generated CN fixed code vector (Word16)
+ pSeed = Updated CN generator shift register state (Word16)
+ pOverflow -> 1 if overflow occured
+
+ Returns:
+ None
+
+ Global Variables Used:
+ None
+
+ Local Variables Needed:
+ None
+
+------------------------------------------------------------------------------
+ FUNCTION DESCRIPTION
+
+This function computes the comfort noise fixed codebook excitation. The gains
+of the pulses are always +/-1.
+
+------------------------------------------------------------------------------
+ REQUIREMENTS
+
+ None
+
+------------------------------------------------------------------------------
+ REFERENCES
+
+ b_cn_cod.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001
+
+------------------------------------------------------------------------------
+ PSEUDO-CODE
+
+void build_CN_code (
+ Word32 *seed, // i/o : Old CN generator shift register state
+ Word16 cod[] // o : Generated CN fixed codebook vector
+)
+{
+ Word16 i, j, k;
+
+ for (i = 0; i < L_SUBFR; i++)
+ {
+ cod[i] = 0;
+ }
+
+// The reference ETSI code uses a global flag for Overflow. However in the
+// actual implementation a pointer to the overflow flag is passed into the
+// function so that it can be passed into the basic math functions L_mult()
+// and add()
+
+ for (k = 0; k < NB_PULSE; k++)
+ {
+ i = pseudonoise (seed, 2); // generate pulse position
+ i = shr (extract_l (L_mult (i, 10)), 1);
+ i = add (i, k);
+
+ j = pseudonoise (seed, 1); // generate sign
+
+ if (j > 0)
+ {
+ cod[i] = 4096;
+ }
+ else
+ {
+ cod[i] = -4096;
+ }
+ }
+
+ return;
+}
+------------------------------------------------------------------------------
+ CAUTION [optional]
+ [State any special notes, constraints or cautions for users of this function]
+
+------------------------------------------------------------------------------
+*/
+
+/*----------------------------------------------------------------------------
+; FUNCTION CODE
+----------------------------------------------------------------------------*/
+void build_CN_code(
+ Word32 *pSeed, /* i/o : Old CN generator shift register state */
+ Word16 cod[], /* o : Generated CN fixed codebook vector */
+ Flag *pOverflow /* i/o : Overflow flag */
+)
+{
+ Word16 i, j, k;
+ Word16 temp;
+
+ for (i = 0; i < L_SUBFR; i++)
+ {
+ cod[i] = 0;
+ }
+
+ for (k = 0; k < NB_PULSE; k++)
+ {
+ i = pseudonoise(pSeed, 2); /* generate pulse position */
+
+ temp = (Word16)(L_mult(i, 10, pOverflow));
+ i = temp >> 1;
+ i = add_16(i, k, pOverflow);
+
+ j = pseudonoise(pSeed, 1); /* generate sign */
+
+ if (j > 0)
+ {
+ cod[i] = 4096;
+ }
+ else
+ {
+ cod[i] = -4096;
+ }
+ }
+
+ return;
+}
+
+/*
+------------------------------------------------------------------------------
+ FUNCTION NAME: build_CN_param
+------------------------------------------------------------------------------
+ INPUT AND OUTPUT DEFINITIONS
+
+ Inputs:
+ pSeed = pointer to the Old CN generator shift register state (Word32)
+ n_param = Number of parameters to randomize (Word16)
+ param_size_table = table holding paameter sizes (Word16)
+ param[] = array to hold CN generated paramters (Word16)
+ pOverflow = pointer to overflow flag (Flag)
+
+ Outputs:
+ param[] = CN generated parameters (Word16)
+ pSeed = Updated CN generator shift register state (Word16)
+ pOverflow -> 1 if overflow occured
+
+ Returns:
+ None
+
+ Global Variables Used:
+ None
+
+ Local Variables Needed:
+ None
+
+------------------------------------------------------------------------------
+ FUNCTION DESCRIPTION
+
+This function randomizes the speech parameters, so that they do not produce
+tonal artifacts if used by ECU.
+
+------------------------------------------------------------------------------
+ REQUIREMENTS
+
+ None
+
+------------------------------------------------------------------------------
+ REFERENCES
+
+ b_cn_cod.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001
+
+------------------------------------------------------------------------------
+ PSEUDO-CODE
+void build_CN_param (
+ Word16 *seed, // i/o : Old CN generator shift register state
+ const Word16 n_param, // i : number of params
+ const Word16 param_size_table[],// i : size of params
+ Word16 parm[] // o : CN Generated params
+ )
+{
+ Word16 i;
+ const Word16 *p;
+
+// The reference ETSI code uses a global flag for Overflow. However in the
+// actual implementation a pointer to the overflow flag is passed into the
+// function so that it can be passed into the basic math functions L_add()
+// and L_mult()
+
+ *seed = extract_l(L_add(L_shr(L_mult(*seed, 31821), 1), 13849L));
+
+ p = &window_200_40[*seed & 0x7F];
+ for(i=0; i< n_param;i++){
+ parm[i] = *p++ & ~(0xFFFF<<param_size_table[i]);
+ }
+}
+
+
+------------------------------------------------------------------------------
+ CAUTION [optional]
+ [State any special notes, constraints or cautions for users of this function]
+
+------------------------------------------------------------------------------
+*/
+
+/*----------------------------------------------------------------------------
+; FUNCTION CODE
+----------------------------------------------------------------------------*/
+void build_CN_param(
+ Word16 *pSeed, /* i/o : Old CN generator shift register state */
+ const Word16 n_param, /* i : number of params */
+ const Word16 param_size_table[],/* i : size of params */
+ Word16 parm[], /* o : CN Generated params */
+ const Word16* window_200_40_ptr, /* i : ptr to read-only table */
+ Flag *pOverflow /* i/o : Overflow Flag */
+)
+
+{
+ Word16 i;
+ const Word16 *pTemp;
+ Word32 L_temp;
+ Word16 temp;
+
+ L_temp = L_mult(*pSeed, 31821, pOverflow);
+ L_temp >>= 1;
+
+ *pSeed = (Word16)(L_add(L_temp, 13849L, pOverflow));
+
+ pTemp = &window_200_40_ptr[*pSeed & 0x7F];
+
+ for (i = 0; i < n_param; i++)
+ {
+ temp = ~(0xFFFF << param_size_table[i]);
+ parm[i] = *pTemp++ & temp;
+ }
+}
+
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