| /* ------------------------------------------------------------------ |
| * 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. |
| ****************************************************************************************/ |
| /* |
| ------------------------------------------------------------------------------ |
| |
| |
| |
| Filename: /audio/gsm_amr/c/src/include/agc.h |
| |
| Date: 12/07/2001 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Removed unneeded sections of the standard template. |
| Updated function prototype for agc() and agc2() to match new |
| interface |
| |
| Description: Changed paramter name from "overflow" to "pOverflow" for |
| functions agc() and agc2() |
| |
| Description: Replaced "int" and/or "char" with OSCL defined types. |
| |
| |
| Description: Moved _cplusplus #ifdef after Include section. |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INCLUDE DESCRIPTION |
| |
| File : agc.h |
| Purpose : Scales the postfilter output on a subframe basis |
| : by automatic control of the subframe gain. |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| #ifndef _AGC_H_ |
| #define _AGC_H_ |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "typedef.h" |
| |
| /*--------------------------------------------------------------------------*/ |
| #ifdef __cplusplus |
| extern "C" |
| { |
| #endif |
| |
| /*---------------------------------------------------------------------------- |
| ; MACROS |
| ; [Define module specific macros here] |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; DEFINES |
| ; [Include all pre-processor statements here.] |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; EXTERNAL VARIABLES REFERENCES |
| ; [Declare variables used in this module but defined elsewhere] |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; SIMPLE TYPEDEF'S |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; ENUMERATED TYPEDEF'S |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; STRUCTURES TYPEDEF'S |
| ----------------------------------------------------------------------------*/ |
| typedef struct |
| { |
| Word16 past_gain; |
| } agcState; |
| |
| /*---------------------------------------------------------------------------- |
| ; GLOBAL FUNCTION DEFINITIONS |
| ; [List function prototypes here] |
| ----------------------------------------------------------------------------*/ |
| /*---------------------------------------------------------------------------- |
| ; |
| ; Function : agc_reset |
| ; Purpose : Reset of agc (i.e. set state memory to 1.0) |
| ; Returns : 0 on success |
| ; |
| ----------------------------------------------------------------------------*/ |
| Word16 agc_reset(agcState *st); |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; |
| ; Function : agc |
| ; Purpose : Scales the postfilter output on a subframe basis |
| ; Description : sig_out[n] = sig_out[n] * gain[n]; |
| ; where gain[n] is the gain at the nth sample given by |
| ; gain[n] = agc_fac * gain[n-1] + (1 - agc_fac) g_in/g_out |
| ; g_in/g_out is the square root of the ratio of energy at |
| ; the input and output of the postfilter. |
| ; |
| ----------------------------------------------------------------------------*/ |
| void agc( |
| agcState *st, /* i/o : agc state */ |
| Word16 *sig_in, /* i : postfilter input signal, (l_trm) */ |
| Word16 *sig_out, /* i/o : postfilter output signal, (l_trm) */ |
| Word16 agc_fac, /* i : AGC factor */ |
| Word16 l_trm, /* i : subframe size */ |
| Flag *pOverflow /* i : overflow flag */ |
| ); |
| |
| /*---------------------------------------------------------------------------- |
| ; |
| ; Function: agc2 |
| ; Purpose: Scales the excitation on a subframe basis |
| ; |
| ----------------------------------------------------------------------------*/ |
| void agc2( |
| Word16 *sig_in, /* i : postfilter input signal */ |
| Word16 *sig_out, /* i/o : postfilter output signal */ |
| Word16 l_trm, /* i : subframe size */ |
| Flag *pOverflow /* i : overflow flag */ |
| ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* _AGC_H_ */ |
| |
| |
