1 /********************************************************************
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. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: PCM data envelope analysis and manipulation
14 last mod: $Id: envelope.h,v 1.23 2002/03/30 01:56:58 xiphmont Exp $
16 ********************************************************************/
26 #define VE_AMP (VE_PRE+VE_POST-1)
31 #define VE_MINSTRETCH 2 /* a bit less than short block */
32 #define VE_MAXSTRETCH 31 /* one full block */
38 float nearDC[VE_NEARDC];
40 float nearDC_partialacc;
44 } envelope_filter_state;
62 envelope_band band[VE_BANDS];
63 envelope_filter_state *filter;
74 extern void _ve_envelope_init(envelope_lookup *e,vorbis_info *vi);
75 extern void _ve_envelope_clear(envelope_lookup *e);
76 extern long _ve_envelope_search(vorbis_dsp_state *v);
77 extern void _ve_envelope_shift(envelope_lookup *e,long shift);
78 extern int _ve_envelope_mark(vorbis_dsp_state *v);