1/********************************************************************
2 * *
3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
7 * *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
9 * by the Xiph.Org Foundation https://xiph.org/ *
10 * *
11 ********************************************************************
12
13 function: PCM data envelope analysis and manipulation
14
15 ********************************************************************/
16
17#ifndef _V_ENVELOPE_
18#define _V_ENVELOPE_
19
20#include "mdct.h"
21
22#define VE_PRE 16
23#define VE_WIN 4
24#define VE_POST 2
25#define VE_AMP (VE_PRE+VE_POST-1)
26
27#define VE_BANDS 7
28#define VE_NEARDC 15
29
30#define VE_MINSTRETCH 2 /* a bit less than short block */
31#define VE_MAXSTRETCH 12 /* one-third full block */
32
33typedef struct {
34 float ampbuf[VE_AMP];
35 int ampptr;
36
37 float nearDC[VE_NEARDC];
38 float nearDC_acc;
39 float nearDC_partialacc;
40 int nearptr;
41
42} envelope_filter_state;
43
44typedef struct {
45 int begin;
46 int end;
47 float *window;
48 float total;
49} envelope_band;
50
51typedef struct {
52 int ch;
53 int winlength;
54 int searchstep;
55 float minenergy;
56
57 mdct_lookup mdct;
58 float *mdct_win;
59
60 envelope_band band[VE_BANDS];
61 envelope_filter_state *filter;
62 int stretch;
63
64 int *mark;
65
66 long storage;
67 long current;
68 long curmark;
69 long cursor;
70} envelope_lookup;
71
72extern void _ve_envelope_init(envelope_lookup *e,vorbis_info *vi);
73extern void _ve_envelope_clear(envelope_lookup *e);
74extern long _ve_envelope_search(vorbis_dsp_state *v);
75extern void _ve_envelope_shift(envelope_lookup *e,long shift);
76extern int _ve_envelope_mark(vorbis_dsp_state *v);
77
78
79#endif
80