| /* ------------------------------------------------------------------ |
| * 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/int_lsf.c |
| |
| Date: 04/20/2000 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Put file into template and first pass at optimization. |
| |
| Description: Made changes based on comments from the review meeting. Used |
| pointers instead of index addressing in the arrays. |
| |
| Description: Added type definition to the input/output section. Fixed tabs. |
| Deleted pseudo-code. |
| |
| Description: Synchronized file with UMTS versin 3.2.0. Updated coding |
| template. Removed unnecessary include files. |
| |
| Description: Made the following changes per comments from Phase 2/3 review: |
| 1. Modified FOR loops to count down. |
| 2. Made some cosmetic changes in the Pseudo-code section. |
| |
| Description: Changed to pass in overflow flag pointer to the add() routine. |
| |
| Description: Replaced "int" and/or "char" with OSCL defined types. |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "int_lsf.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. |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL FUNCTION DEFINITIONS |
| ; Function Prototype declaration |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL STORE/BUFFER/POINTER DEFINITIONS |
| ; Variable declaration - defined here and used outside this module |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /* |
| ------------------------------------------------------------------------------ |
| FUNCTION NAME: Int_lsf |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| lsf_old = LSF vector at the 4th SF of past frame (Word16) |
| lsf_new = LSF vector at the 4th SF of present frame (Word16) |
| i_subfr = Current subframe (equal to 0,40,80 or 120) (Word16) |
| lsf_out = interpolated LSF parameters for current subframe (Word16) |
| |
| Outputs: |
| lsf_out = new interpolated LSF parameters for current subframe |
| pOverflow = pointer of type Flag * to overflow indicator. |
| |
| Returns: |
| None. |
| |
| Global Variables Used: |
| None. |
| |
| Local Variables Needed: |
| None. |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function interpolates the LSFs for selected subframe. |
| The 20 ms speech frame is divided into 4 subframes. The LSFs are |
| interpolated at the 1st, 2nd and 3rd subframe and only forwarded |
| at the 4th subframe. |
| |
| |------|------|------|------| |
| sf1 sf2 sf3 sf4 |
| F0 F1 |
| |
| sf1: 3/4 F0 + 1/4 F1 sf3: 1/4 F0 + 3/4 F1 |
| sf2: 1/2 F0 + 1/2 F1 sf4: F1 |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| None. |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| int_lsf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| void Int_lsf( |
| Word16 lsf_old[], // i : LSF vector at the 4th SF of past frame |
| Word16 lsf_new[], // i : LSF vector at the 4th SF of present frame |
| Word16 i_subfr, // i : Pointer to current sf (equal to 0,40,80 or 120) |
| Word16 lsf_out[] // o : interpolated LSF parameters for current sf |
| ) |
| { |
| Word16 i; |
| |
| if ( i_subfr == 0 ) |
| { |
| for (i = 0; i < M; i++) { |
| lsf_out[i] = add(sub(lsf_old[i], shr(lsf_old[i], 2)), |
| shr(lsf_new[i], 2)); |
| } |
| } |
| else if ( sub(i_subfr, 40) == 0 ) |
| { |
| for (i = 0; i < M; i++) { |
| lsf_out[i] = add(shr(lsf_old[i],1), shr(lsf_new[i], 1) ); |
| } |
| } |
| else if ( sub(i_subfr, 80) == 0 ) |
| { |
| for (i = 0; i < M; i++) { |
| lsf_out[i] = add(shr(lsf_old[i], 2), |
| sub(lsf_new[i], shr(lsf_new[i], 2))); |
| } |
| } |
| else if ( sub(i_subfr, 120) == 0 ) |
| { |
| for (i = 0; i < M; i++) { |
| lsf_out[i] = lsf_new[i]; |
| } |
| } |
| |
| return; |
| } |
| |
| ------------------------------------------------------------------------------ |
| 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] |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| void Int_lsf( |
| Word16 lsf_old[], /* i : LSF vector at the 4th SF of past frame */ |
| Word16 lsf_new[], /* i : LSF vector at the 4th SF of present frame */ |
| Word16 i_subfr, /* i : Current sf (equal to 0,40,80 or 120) */ |
| Word16 lsf_out[], /* o : interpolated LSF parameters for current sf */ |
| Flag *pOverflow /* o : flag set if overflow occurs */ |
| ) |
| { |
| register Word16 i; |
| register Word16 temp1; |
| register Word16 temp2; |
| |
| if (i_subfr == 0) |
| { |
| for (i = M - 1; i >= 0; i--) |
| { |
| if (*(lsf_old + i) < 0) |
| { |
| temp1 = ~(~(*(lsf_old + i)) >> 2); |
| } |
| else |
| { |
| temp1 = *(lsf_old + i) >> 2; |
| } |
| if (*(lsf_new + i) < 0) |
| { |
| temp2 = ~(~(*(lsf_new + i)) >> 2); |
| } |
| else |
| { |
| temp2 = *(lsf_new + i) >> 2; |
| } |
| *(lsf_out + i) = add((Word16)(*(lsf_old + i) - temp1), |
| (Word16)temp2, |
| pOverflow); |
| } |
| } |
| |
| else if (i_subfr == 40) |
| { |
| for (i = M - 1; i >= 0; i--) |
| { |
| if (*(lsf_old + i) < 0) |
| { |
| temp1 = ~(~(*(lsf_old + i)) >> 1); |
| } |
| else |
| { |
| temp1 = *(lsf_old + i) >> 1; |
| } |
| if (*(lsf_new + i) < 0) |
| { |
| temp2 = ~(~(*(lsf_new + i)) >> 1); |
| } |
| else |
| { |
| temp2 = *(lsf_new + i) >> 1; |
| } |
| *(lsf_out + i) = add( |
| temp1, |
| temp2, |
| pOverflow); |
| } |
| } |
| |
| else if (i_subfr == 80) |
| { |
| for (i = M - 1; i >= 0; i--) |
| { |
| if (*(lsf_old + i) < 0) |
| { |
| temp1 = ~(~(*(lsf_old + i)) >> 2); |
| } |
| else |
| { |
| temp1 = *(lsf_old + i) >> 2; |
| } |
| if (*(lsf_new + i) < 0) |
| { |
| temp2 = ~(~(*(lsf_new + i)) >> 2); |
| } |
| else |
| { |
| temp2 = *(lsf_new + i) >> 2; |
| } |
| *(lsf_out + i) = add((Word16)temp1, |
| (Word16)(*(lsf_new + i) - temp2), |
| pOverflow); |
| |
| } |
| } |
| |
| else if (i_subfr == 120) |
| { |
| for (i = M - 1; i >= 0; i--) |
| { |
| *(lsf_out + i) = *(lsf_new + i); |
| } |
| } |
| |
| return; |
| } |
| |
