| /* ------------------------------------------------------------------ |
| * 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/residu.c |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Updated template used to PV coding template. First attempt at |
| optimizing code. |
| |
| Description: Deleted stores listed in the Local Stores Needed/Modified |
| section. |
| |
| Description: Updated file per comments gathered from Phase 2/3 review. |
| |
| Description: Updating to reflect variable name changes made in residu.asm |
| |
| Description: Synchronized file with UMTS version 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. Fixed typecasting issue with TI C compiler. |
| |
| Description: Made the following changes |
| 1. Unrolled the convolutional loop. |
| 2. Performed 4 convolution per pass to avoid recalling the same |
| filter coefficient as many times. |
| 2. Eliminated math operations that check for saturation. |
| |
| Description: Replaced "int" and/or "char" with OSCL defined types. |
| |
| Description: Changed round function name to pv_round to avoid conflict with |
| round function in C standard library. |
| |
| Who: Date: |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "residu.h" |
| #include "typedef.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: Residu |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| coef_ptr = pointer to buffer containing the prediction coefficients |
| input_ptr = pointer to buffer containing the speech signal |
| input_len = filter order |
| residual_ptr = pointer to buffer of residual signal |
| |
| Outputs: |
| residual_ptr buffer contains the newly calculated the residual signal |
| |
| Returns: |
| None |
| |
| Global Variables Used: |
| None |
| |
| Local Variables Needed: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function computes the LP residual by filtering the input speech through |
| the LP inverse filter A(z). |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| None |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| residu.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| Note: Input argument names were changed to be more descriptive. Shown below |
| are the original names. Shown below are the name changes: |
| a[] <--> coef_ptr[] |
| x[] <--> input_ptr[] |
| y[] <--> residual_ptr[] |
| lg <--> input_len |
| |
| |
| void Residu ( |
| Word16 a[], // (i) : prediction coefficients |
| Word16 x[], // (i) : speech signal |
| Word16 y[], // (o) : residual signal |
| Word16 lg // (i) : size of filtering |
| ) |
| { |
| Word16 i, j; |
| Word32 s; |
| |
| for (i = 0; i < lg; i++) |
| { |
| s = L_mult (x[i], a[0]); |
| for (j = 1; j <= M; j++) |
| { |
| s = L_mac (s, a[j], x[i - j]); |
| } |
| s = L_shl (s, 3); |
| y[i] = pv_round (s); |
| } |
| 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 Residu( |
| Word16 coef_ptr[], /* (i) : prediction coefficients*/ |
| Word16 input_ptr[], /* (i) : speech signal */ |
| Word16 residual_ptr[], /* (o) : residual signal */ |
| Word16 input_len /* (i) : size of filtering */ |
| ) |
| { |
| |
| |
| Word16 i, j; |
| Word32 s1; |
| Word32 s2; |
| Word32 s3; |
| Word32 s4; |
| Word16 *p_input1; |
| Word16 *p_input2; |
| Word16 *p_input3; |
| Word16 *p_input4; |
| Word16 *p_coef; |
| Word16 *p_residual_ptr = &residual_ptr[input_len-1]; |
| Word16 *p_input_ptr = &input_ptr[input_len-1-M]; |
| |
| for (i = input_len >> 2; i != 0; i--) |
| { |
| s1 = 0x0000800L; |
| s2 = 0x0000800L; |
| s3 = 0x0000800L; |
| s4 = 0x0000800L; |
| p_coef = &coef_ptr[M]; |
| p_input1 = p_input_ptr--; |
| p_input2 = p_input_ptr--; |
| p_input3 = p_input_ptr--; |
| p_input4 = p_input_ptr--; |
| |
| for (j = M >> 1; j != 0; j--) |
| { |
| s1 += ((Word32) * (p_coef) * *(p_input1++)); |
| s2 += ((Word32) * (p_coef) * *(p_input2++)); |
| s3 += ((Word32) * (p_coef) * *(p_input3++)); |
| s4 += ((Word32) * (p_coef--) * *(p_input4++)); |
| s1 += ((Word32) * (p_coef) * *(p_input1++)); |
| s2 += ((Word32) * (p_coef) * *(p_input2++)); |
| s3 += ((Word32) * (p_coef) * *(p_input3++)); |
| s4 += ((Word32) * (p_coef--) * *(p_input4++)); |
| } |
| |
| s1 += (((Word32) * (p_coef)) * *(p_input1)); |
| s2 += (((Word32) * (p_coef)) * *(p_input2)); |
| s3 += (((Word32) * (p_coef)) * *(p_input3)); |
| s4 += (((Word32) * (p_coef)) * *(p_input4)); |
| |
| *(p_residual_ptr--) = (Word16)(s1 >> 12); |
| *(p_residual_ptr--) = (Word16)(s2 >> 12); |
| *(p_residual_ptr--) = (Word16)(s3 >> 12); |
| *(p_residual_ptr--) = (Word16)(s4 >> 12); |
| |
| } |
| |
| return; |
| } |
