michael@0: /********************************************************************
michael@0:  *                                                                  *
michael@0:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
michael@0:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
michael@0:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
michael@0:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
michael@0:  *                                                                  *
michael@0:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
michael@0:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
michael@0:  *                                                                  *
michael@0:  ********************************************************************
michael@0: 
michael@0:  function: PCM data envelope analysis and manipulation
michael@0:  last mod: $Id: envelope.h 16227 2009-07-08 06:58:46Z xiphmont $
michael@0: 
michael@0:  ********************************************************************/
michael@0: 
michael@0: #ifndef _V_ENVELOPE_
michael@0: #define _V_ENVELOPE_
michael@0: 
michael@0: #include "mdct.h"
michael@0: 
michael@0: #define VE_PRE    16
michael@0: #define VE_WIN    4
michael@0: #define VE_POST   2
michael@0: #define VE_AMP    (VE_PRE+VE_POST-1)
michael@0: 
michael@0: #define VE_BANDS  7
michael@0: #define VE_NEARDC 15
michael@0: 
michael@0: #define VE_MINSTRETCH 2   /* a bit less than short block */
michael@0: #define VE_MAXSTRETCH 12  /* one-third full block */
michael@0: 
michael@0: typedef struct {
michael@0:   float ampbuf[VE_AMP];
michael@0:   int   ampptr;
michael@0: 
michael@0:   float nearDC[VE_NEARDC];
michael@0:   float nearDC_acc;
michael@0:   float nearDC_partialacc;
michael@0:   int   nearptr;
michael@0: 
michael@0: } envelope_filter_state;
michael@0: 
michael@0: typedef struct {
michael@0:   int begin;
michael@0:   int end;
michael@0:   float *window;
michael@0:   float total;
michael@0: } envelope_band;
michael@0: 
michael@0: typedef struct {
michael@0:   int ch;
michael@0:   int winlength;
michael@0:   int searchstep;
michael@0:   float minenergy;
michael@0: 
michael@0:   mdct_lookup  mdct;
michael@0:   float       *mdct_win;
michael@0: 
michael@0:   envelope_band          band[VE_BANDS];
michael@0:   envelope_filter_state *filter;
michael@0:   int   stretch;
michael@0: 
michael@0:   int                   *mark;
michael@0: 
michael@0:   long storage;
michael@0:   long current;
michael@0:   long curmark;
michael@0:   long cursor;
michael@0: } envelope_lookup;
michael@0: 
michael@0: extern void _ve_envelope_init(envelope_lookup *e,vorbis_info *vi);
michael@0: extern void _ve_envelope_clear(envelope_lookup *e);
michael@0: extern long _ve_envelope_search(vorbis_dsp_state *v);
michael@0: extern void _ve_envelope_shift(envelope_lookup *e,long shift);
michael@0: extern int  _ve_envelope_mark(vorbis_dsp_state *v);
michael@0: 
michael@0: 
michael@0: #endif