| /* ------------------------------------------------------------------ |
| * 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. |
| ****************************************************************************************/ |
| /* |
| ------------------------------------------------------------------------------ |
| |
| |
| |
| Pathname: ./audio/gsm-amr/c/src/ex_ctrl.c |
| Funtions: ex_ctrl |
| |
| Date: 02/08/2002 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Replaced "int" and/or "char" with OSCL defined types. |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "ex_ctrl.h" |
| #include "typedef.h" |
| #include "cnst.h" |
| #include "copy.h" |
| #include "set_zero.h" |
| #include "gmed_n.h" |
| #include "sqrt_l.h" |
| #include "basic_op.h" |
| /*---------------------------------------------------------------------------- |
| ; MACROS |
| ; Define module specific macros here |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; DEFINES |
| ; Include all pre-processor statements here. Include conditional |
| ; compile variables also. |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL FUNCTION DEFINITIONS |
| ; Function Prototype declaration |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL VARIABLE DEFINITIONS |
| ; Variable declaration - defined here and used outside this module |
| ----------------------------------------------------------------------------*/ |
| |
| /* |
| ------------------------------------------------------------------------------ |
| FUNCTION NAME: ex_ctrl |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| excitation = pointer to current subframe excitation of type Word16 |
| excEnergy = Exc. Energy, sqrt(totEx*totEx) of type Word16 |
| exEnergyHist = pointer to history of subframe energies of type Word16 |
| voicedHangover = # of fr. after last voiced fr of type Word16 |
| carefulFlag = restrict dynamic in scaling of type Word16 |
| pOverflow = pointer to overflow indicator |
| |
| Outputs: |
| pOverflow = 1 if overflow exists in the math functions called by this function. |
| |
| Returns: |
| None |
| |
| Global Variables Used: |
| None |
| |
| Local Variables Needed: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| Function : Ex_ctrl |
| Purpose : Charaterice synthesis speech and detect background noise |
| Returns : background noise decision; 0 = no bgn, 1 = bgn |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| None |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| ex_ctrl.c, 3GPP TS 26.101 version 4.1.0 Release 4, June 2001 |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| |
| |
| ------------------------------------------------------------------------------ |
| RESOURCES USED [optional] |
| |
| When the code is written for a specific target processor the |
| the resources used should be documented below. |
| |
| HEAP MEMORY USED: x bytes |
| |
| STACK MEMORY USED: x bytes |
| |
| CLOCK CYCLES: (cycle count equation for this function) + (variable |
| used to represent cycle count for each subroutine |
| called) |
| where: (cycle count variable) = cycle count for [subroutine |
| name] |
| |
| ------------------------------------------------------------------------------ |
| CAUTION [optional] |
| [State any special notes, constraints or cautions for users of this function] |
| |
| ------------------------------------------------------------------------------ |
| */ |
| Word16 Ex_ctrl(Word16 excitation[], /*i/o: Current subframe excitation */ |
| Word16 excEnergy, /* i : Exc. Energy, sqrt(totEx*totEx)*/ |
| Word16 exEnergyHist[], /* i : History of subframe energies */ |
| Word16 voicedHangover, /* i : # of fr. after last voiced fr.*/ |
| Word16 prevBFI, /* i : Set i previous BFI */ |
| Word16 carefulFlag, /* i : Restrict dymamic in scaling */ |
| Flag *pOverflow |
| ) |
| { |
| Word16 i, exp; |
| Word16 testEnergy, scaleFactor, avgEnergy, prevEnergy; |
| Word32 t0; |
| |
| /* get target level */ |
| avgEnergy = gmed_n(exEnergyHist, 9); |
| |
| prevEnergy = shr(add(exEnergyHist[7], exEnergyHist[8], pOverflow) , 1, pOverflow); |
| |
| if (exEnergyHist[8] < prevEnergy) |
| { |
| prevEnergy = exEnergyHist[8]; |
| } |
| |
| /* upscaling to avoid too rapid energy rises for some cases */ |
| if ((excEnergy < avgEnergy) && (excEnergy > 5)) |
| { |
| testEnergy = shl(prevEnergy, 2, pOverflow); /* testEnergy = 4*prevEnergy; */ |
| |
| if ((voicedHangover < 7) || prevBFI != 0) |
| { |
| /* testEnergy = 3*prevEnergy */ |
| testEnergy = sub(testEnergy, prevEnergy, pOverflow); |
| } |
| |
| if (avgEnergy > testEnergy) |
| { |
| avgEnergy = testEnergy; |
| } |
| |
| /* scaleFactor=avgEnergy/excEnergy in Q0 (const 29 below)*/ |
| exp = norm_s(excEnergy); |
| excEnergy = shl(excEnergy, exp, pOverflow); |
| excEnergy = div_s((Word16) 16383, excEnergy); |
| t0 = L_mult(avgEnergy, excEnergy, pOverflow); |
| t0 = L_shr(t0, sub(20, exp, pOverflow), pOverflow); |
| /* const=30 for t0 in Q0, 20 for Q10 */ |
| if (t0 > 32767) |
| { |
| t0 = 32767; /* saturate */ |
| } |
| scaleFactor = extract_l(t0); |
| |
| /* test if scaleFactor > 3.0 */ |
| if (carefulFlag != 0 && (scaleFactor > 3072)) |
| { |
| scaleFactor = 3072; |
| } |
| |
| /* scale the excitation by scaleFactor */ |
| for (i = 0; i < L_SUBFR; i++) |
| { |
| t0 = L_mult(scaleFactor, excitation[i], pOverflow); |
| t0 = L_shr(t0, 11, pOverflow); |
| excitation[i] = extract_l(t0); |
| } |
| } |
| |
| return 0; |
| } |