📄 d8_31pf.cpp
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/* ------------------------------------------------------------------ * Copyright (C) 2008 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 licenseterms listed above has been obtained from the copyright holder.****************************************************************************************//*------------------------------------------------------------------------------ Pathname: ./audio/gsm-amr/c/src/d8_31pf.c Functions: Date: 01/28/2002------------------------------------------------------------------------------ REVISION HISTORY Description: Modified to pass overflow flag through to basic math function. The flag is passed back to the calling function by pointer reference. Description: Per review comments... (1) Removed include of "count.h" and "basic_op.h" (2) Added includes of mult.h, shl.h, shr.h, add.h, sub.h, negate.h, L_mult.h, and L_shr.h Description: Replaced "int" and/or "char" with OSCL defined types. Description:------------------------------------------------------------------------------ MODULE DESCRIPTION*//*----------------------------------------------------------------------------; INCLUDES----------------------------------------------------------------------------*/#include "d8_31pf.h"#include "typedef.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 8 /* number of pulses *//* define values/representation for output codevector and sign */#define POS_CODE 8191#define NEG_CODE 8191/*----------------------------------------------------------------------------; LOCAL FUNCTION DEFINITIONS; Function Prototype declaration----------------------------------------------------------------------------*//*----------------------------------------------------------------------------; LOCAL VARIABLE DEFINITIONS; Variable declaration - defined here and used outside this module----------------------------------------------------------------------------*//*------------------------------------------------------------------------------ FUNCTION NAME: decompress10------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: MSBs -- Word16 -- MSB part of the index LSBs -- Word16 -- LSB part of the index index1 -- Word16 -- index for first pos in pos_index[] index2 -- Word16 -- index for second pos in pos_index[] index3 -- Word16 -- index for third pos in pos_index[] Outputs: pos_indx[] -- array of type Word16 -- position of 3 pulses (decompressed) pOverflow Flag set when overflow occurs, pointer of type Flag * Returns: None Global Variables Used: None Local Variables Needed: None------------------------------------------------------------------------------ FUNCTION DESCRIPTION------------------------------------------------------------------------------ REQUIREMENTS None------------------------------------------------------------------------------ REFERENCES d8_31pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 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]------------------------------------------------------------------------------*/static void decompress10( Word16 MSBs, /* i : MSB part of the index */ Word16 LSBs, /* i : LSB part of the index */ Word16 index1, /* i : index for first pos in pos_index[] */ Word16 index2, /* i : index for second pos in pos_index[] */ Word16 index3, /* i : index for third pos in pos_index[] */ Word16 pos_indx[], /* o : position of 3 pulses (decompressed) */ Flag *pOverflow) /* o : Flag set when overflow occurs */{ Word16 ia; Word16 ib; Word16 ic; Word32 tempWord32; /* pos_indx[index1] = ((MSBs-25*(MSBs/25))%5)*2 + (LSBs-4*(LSBs/4))%2; pos_indx[index2] = ((MSBs-25*(MSBs/25))/5)*2 + (LSBs-4*(LSBs/4))/2; pos_indx[index3] = (MSBs/25)*2 + LSBs/4; */ if (MSBs > 124) { MSBs = 124; } ia = mult( MSBs, 1311, pOverflow); tempWord32 = L_mult( ia, 25, pOverflow); ia = (Word16) L_shr( tempWord32, 1, pOverflow); ia = sub( MSBs, ia, pOverflow); ib = mult( ia, 6554, pOverflow); tempWord32 = L_mult( ib, 5, pOverflow); ib = (Word16) L_shr( tempWord32, 1, pOverflow); ib = sub( ia, ib, pOverflow); ib = shl( ib, 1, pOverflow); ic = shr( LSBs, 2, pOverflow); ic = shl( ic, 2, pOverflow); ic = sub( LSBs, ic, pOverflow); pos_indx[index1] = add( (Word16)ib, (Word16)(ic & 0x1), pOverflow); ib = mult( ia, 6554, pOverflow); ib = shl( ib, 1, pOverflow); ic = shr( ic, 1, pOverflow); pos_indx[index2] = add( ib, ic, pOverflow); ib = shr( LSBs, 2, pOverflow); ic = mult( MSBs, 1311, pOverflow); ic = shl( ic, 1, pOverflow); pos_indx[index3] = add( ib, ic, pOverflow); return;}/*------------------------------------------------------------------------------ FUNCTION NAME: decompress_code------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: indx[] -- array of type Word16 -- position and sign of 8 pulses (compressed) Outputs: sign_indx[] -- array of type Word16 -- signs of 4 pulses (signs only) pos_indx[] -- array of type Word16 -- position index of 8 pulses (position only) pOverflow pointer to type Flag -- Flag set when overflow occurs Returns: None Global Variables Used: None Local Variables Needed: None------------------------------------------------------------------------------ FUNCTION DESCRIPTION PURPOSE: decompression of the linear codewords to 4+three indeces one bit from each pulse is made robust to errors by minimizing the phase shift of a bit error. 4 signs (one for each track) i0,i4,i1 => one index (7+3) bits, 3 LSBs more robust i2,i6,i5 => one index (7+3) bits, 3 LSBs more robust i3,i7 => one index (5+2) bits, 2-3 LSbs more robust------------------------------------------------------------------------------ REQUIREMENTS None------------------------------------------------------------------------------ REFERENCES d8_31pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 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⌨️ 快捷键说明
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