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Diffstat (limited to 'media/libstagefright/codecs/amrnb/dec/src/ex_ctrl.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/dec/src/ex_ctrl.cpp | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/dec/src/ex_ctrl.cpp b/media/libstagefright/codecs/amrnb/dec/src/ex_ctrl.cpp new file mode 100644 index 0000000..f18054b --- /dev/null +++ b/media/libstagefright/codecs/amrnb/dec/src/ex_ctrl.cpp @@ -0,0 +1,219 @@ +/* ------------------------------------------------------------------ + * 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; +} |