cannam@86: /********************************************************************
cannam@86:  *                                                                  *
cannam@86:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
cannam@86:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
cannam@86:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
cannam@86:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
cannam@86:  *                                                                  *
cannam@86:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
cannam@86:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
cannam@86:  *                                                                  *
cannam@86:  ********************************************************************
cannam@86: 
cannam@86:  function: PCM data envelope analysis and manipulation
cannam@86:  last mod: $Id: envelope.h 16227 2009-07-08 06:58:46Z xiphmont $
cannam@86: 
cannam@86:  ********************************************************************/
cannam@86: 
cannam@86: #ifndef _V_ENVELOPE_
cannam@86: #define _V_ENVELOPE_
cannam@86: 
cannam@86: #include "mdct.h"
cannam@86: 
cannam@86: #define VE_PRE    16
cannam@86: #define VE_WIN    4
cannam@86: #define VE_POST   2
cannam@86: #define VE_AMP    (VE_PRE+VE_POST-1)
cannam@86: 
cannam@86: #define VE_BANDS  7
cannam@86: #define VE_NEARDC 15
cannam@86: 
cannam@86: #define VE_MINSTRETCH 2   /* a bit less than short block */
cannam@86: #define VE_MAXSTRETCH 12  /* one-third full block */
cannam@86: 
cannam@86: typedef struct {
cannam@86:   float ampbuf[VE_AMP];
cannam@86:   int   ampptr;
cannam@86: 
cannam@86:   float nearDC[VE_NEARDC];
cannam@86:   float nearDC_acc;
cannam@86:   float nearDC_partialacc;
cannam@86:   int   nearptr;
cannam@86: 
cannam@86: } envelope_filter_state;
cannam@86: 
cannam@86: typedef struct {
cannam@86:   int begin;
cannam@86:   int end;
cannam@86:   float *window;
cannam@86:   float total;
cannam@86: } envelope_band;
cannam@86: 
cannam@86: typedef struct {
cannam@86:   int ch;
cannam@86:   int winlength;
cannam@86:   int searchstep;
cannam@86:   float minenergy;
cannam@86: 
cannam@86:   mdct_lookup  mdct;
cannam@86:   float       *mdct_win;
cannam@86: 
cannam@86:   envelope_band          band[VE_BANDS];
cannam@86:   envelope_filter_state *filter;
cannam@86:   int   stretch;
cannam@86: 
cannam@86:   int                   *mark;
cannam@86: 
cannam@86:   long storage;
cannam@86:   long current;
cannam@86:   long curmark;
cannam@86:   long cursor;
cannam@86: } envelope_lookup;
cannam@86: 
cannam@86: extern void _ve_envelope_init(envelope_lookup *e,vorbis_info *vi);
cannam@86: extern void _ve_envelope_clear(envelope_lookup *e);
cannam@86: extern long _ve_envelope_search(vorbis_dsp_state *v);
cannam@86: extern void _ve_envelope_shift(envelope_lookup *e,long shift);
cannam@86: extern int  _ve_envelope_mark(vorbis_dsp_state *v);
cannam@86: 
cannam@86: 
cannam@86: #endif