ref: 26fbba4eb876e7147570f036c4bcba241c84529d
dir: /aac_back_pred.h/
/********************************************************************** This software module was originally developed by and edited by Nokia in the course of development of the MPEG-2 NBC/MPEG-4 Audio standard ISO/IEC 13818-7, 14496-1,2 and 3. This software module is an implementation of a part of one or more MPEG-2 NBC/MPEG-4 Audio tools as specified by the MPEG-2 NBC/MPEG-4 Audio standard. ISO/IEC gives users of the MPEG-2 NBC/MPEG-4 Audio standards free license to this software module or modifications thereof for use in hardware or software products claiming conformance to the MPEG-2 NBC/ MPEG-4 Audio standards. Those intending to use this software module in hardware or software products are advised that this use may infringe existing patents. The original developer of this software module and his/her company, the subsequent editors and their companies, and ISO/IEC have no liability for use of this software module or modifications thereof in an implementation. Copyright is not released for non MPEG-2 NBC/MPEG-4 Audio conforming products. The original developer retains full right to use the code for his/her own purpose, assign or donate the code to a third party and to inhibit third party from using the code for non MPEG-2 NBC/MPEG-4 Audio conforming products. This copyright notice must be included in all copies or derivative works. Copyright (c) 1997. **********************************************************************/ /********************************************************************* * * aac_back_pred.c - AAC backward prediction subroutine * * Authors: * LY Lin Yin, Nokia Research Center * CL Chuck Lueck, TI <lueck@ti.com> * ADD Alberto Duenas, NDS <alberto@ndsuk.com> * JB Jeremy Bennett, NDS <jbennett@ndsuk.com> * * Changes: * 07-jun-97 LY Initial revision. * 14-sep-97 CL Updated ALPHA, A, and B coefficients. * 03-dec-97 ADD & JB Added prediction reset. * **********************************************************************/ #ifndef _AAC_BACK_H_INCLUDED #define _AAC_BACK_H_INCLUDED #include <math.h> #include "interface.h" #include "all.h" #define FLEN_LONG 2048 #define SBMAX_L 49 #define LPC 2 #define ALPHA PRED_ALPHA #define A PRED_A #define B PRED_B #define MINVAR 1.e-10 /* Reset every RESET_FRAME frames. */ #define RESET_FRAME 8 void PredCalcPrediction( double *act_spec, double *last_spec, int btype, int nsfb, int *isfb_width, short *pred_global_flag, int *pred_sfb_flag, int *reset_group, int chanNum); void PredInit(); #endif