| /* ------------------------------------------------------------------ |
| * 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/d_gain_c.c |
| Functions: d_gain_c |
| |
| Date: 01/29/2002 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Updated include files and intput/output section. Changed .tab |
| files to .c files. |
| |
| Description: Replaced OSCL mem type functions and eliminated include |
| files that now are chosen by OSCL definitions |
| |
| Description: Replaced "int" and/or "char" with OSCL defined types. |
| |
| Description: Added #ifdef __cplusplus around extern'ed table. |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| pred_state = pointer to sturcture type gc_predState. MA predictor state |
| mode = AMR mode (MR795 or MR122) of type enum Mode |
| index = received quantization index of type Word16 |
| code[] = pointer to innovation codevector of type Word16 |
| pOverflow= pointer to value indicating existence of overflow (Flag) |
| |
| Outputs: |
| pred_state = pointer to sturcture type gc_predState. MA predictor state |
| gain_code = pointer to decoded innovation gain of type Word16 |
| pOverflow = 1 if there is an overflow else it is zero. |
| |
| Returns: |
| None. |
| |
| Global Variables Used: |
| None |
| |
| Local Variables Needed: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| Function : d_gain_code |
| Purpose : Decode the fixed codebook gain using the received index. |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| d_gain_c.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| |
| |
| ------------------------------------------------------------------------------ |
| RESOURCES USED |
| When the code is written for a specific target processor the |
| the resources used should be documented below. |
| |
| STACK USAGE: [stack count for this module] + [variable to represent |
| stack usage for each subroutine called] |
| |
| where: [stack usage variable] = stack usage for [subroutine |
| name] (see [filename].ext) |
| |
| DATA MEMORY USED: x words |
| |
| PROGRAM MEMORY USED: x words |
| |
| CLOCK CYCLES: [cycle count equation for this module] + [variable |
| used to represent cycle count for each subroutine |
| called] |
| |
| where: [cycle count variable] = cycle count for [subroutine |
| name] (see [filename].ext) |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "d_gain_c.h" |
| #include "typedef.h" |
| #include "mode.h" |
| |
| #include "oper_32b.h" |
| #include "cnst.h" |
| #include "log2.h" |
| #include "pow2.h" |
| #include "gc_pred.h" |
| |
| #include "basic_op.h" |
| |
| /*--------------------------------------------------------------------------*/ |
| #ifdef __cplusplus |
| extern "C" |
| { |
| #endif |
| |
| /*---------------------------------------------------------------------------- |
| ; 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 STORE/BUFFER/POINTER DEFINITIONS |
| ; Variable declaration - defined here and used outside this module |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; EXTERNAL FUNCTION REFERENCES |
| ; Declare functions defined elsewhere and referenced in this module |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES |
| ; Declare variables used in this module but defined elsewhere |
| ----------------------------------------------------------------------------*/ |
| extern const Word16 qua_gain_code[]; |
| |
| |
| /*--------------------------------------------------------------------------*/ |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| /*---------------------------------------------------------------------------- |
| ; FUNCTION CODE |
| ----------------------------------------------------------------------------*/ |
| void d_gain_code( |
| gc_predState *pred_state, /* i/o : MA predictor state */ |
| enum Mode mode, /* i : AMR mode (MR795 or MR122) */ |
| Word16 index, /* i : received quantization index */ |
| Word16 code[], /* i : innovation codevector */ |
| Word16 *gain_code, /* o : decoded innovation gain */ |
| Flag *pOverflow |
| ) |
| { |
| Word16 gcode0, exp, frac; |
| const Word16 *p; |
| Word16 qua_ener_MR122, qua_ener; |
| Word16 exp_inn_en; |
| Word16 frac_inn_en; |
| Word32 L_tmp; |
| Word16 tbl_tmp; |
| Word16 temp; |
| /*-------------- Decode codebook gain ---------------*/ |
| |
| /*-------------------------------------------------------------------* |
| * predict codebook gain * |
| * ~~~~~~~~~~~~~~~~~~~~~ * |
| * gc0 = Pow2(int(d)+frac(d)) * |
| * = 2^exp + 2^frac * |
| * * |
| *-------------------------------------------------------------------*/ |
| |
| gc_pred(pred_state, mode, code, &exp, &frac, |
| &exp_inn_en, &frac_inn_en, pOverflow); |
| |
| index &= 31; /* index < 32, to avoid buffer overflow */ |
| tbl_tmp = index + (index << 1); |
| |
| p = &qua_gain_code[tbl_tmp]; |
| |
| /* Different scalings between MR122 and the other modes */ |
| temp = sub((Word16)mode, (Word16)MR122, pOverflow); |
| if (temp == 0) |
| { |
| gcode0 = (Word16)(Pow2(exp, frac, pOverflow)); /* predicted gain */ |
| gcode0 = shl(gcode0, 4, pOverflow); |
| *gain_code = shl(mult(gcode0, *p++, pOverflow), 1, pOverflow); |
| } |
| else |
| { |
| gcode0 = (Word16)(Pow2(14, frac, pOverflow)); |
| L_tmp = L_mult(*p++, gcode0, pOverflow); |
| L_tmp = L_shr(L_tmp, sub(9, exp, pOverflow), pOverflow); |
| *gain_code = extract_h(L_tmp); /* Q1 */ |
| } |
| |
| /*-------------------------------------------------------------------* |
| * update table of past quantized energies * |
| * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * |
| *-------------------------------------------------------------------*/ |
| qua_ener_MR122 = *p++; |
| qua_ener = *p++; |
| gc_pred_update(pred_state, qua_ener_MR122, qua_ener); |
| |
| return; |
| } |
| |
| |
| |
| |
