text: /********************************************************************
   *                                                                  *
   * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
   * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
   * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
   * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
   *                                                                  *
   * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2002             *
   * by the XIPHOPHORUS Company http://www.xiph.org/                  *
   *                                                                  *
   ********************************************************************
  
   function: libvorbis backend and mapping structures; needed for 
             static mode headers
   last mod: $Id: backends.h,v 1.15 2003/12/30 11:02:22 xiphmont Exp $
  
   ********************************************************************/
  
  /* this is exposed up here because we need it for static modes.
     Lookups for each backend aren't exposed because there's no reason
     to do so */
  
  #ifndef _vorbis_backend_h_
  #define _vorbis_backend_h_
  
  #include "codec_internal.h"
  
  /* this would all be simpler/shorter with templates, but.... */
  /* Floor backend generic *****************************************/
  typedef struct{
    void                   (*pack)  (vorbis_info_floor *,oggpack_buffer *);
    vorbis_info_floor     *(*unpack)(vorbis_info *,oggpack_buffer *);
    vorbis_look_floor     *(*look)  (vorbis_dsp_state *,vorbis_info_floor *);
    void (*free_info) (vorbis_info_floor *);
    void (*free_look) (vorbis_look_floor *);
    void *(*inverse1)  (struct vorbis_block *,vorbis_look_floor *);
    int   (*inverse2)  (struct vorbis_block *,vorbis_look_floor *,
  		     void *buffer,float *);
  } vorbis_func_floor;
  
  typedef struct{
    int   order;
    long  rate;
    long  barkmap;
  
    int   ampbits;
    int   ampdB;
  
    int   numbooks; /* <= 16 */
    int   books[16];
  
    float lessthan;     /* encode-only config setting hacks for libvorbis */
    float greaterthan;  /* encode-only config setting hacks for libvorbis */
  
  } vorbis_info_floor0;
  
  
  #define VIF_POSIT 63
  #define VIF_CLASS 16
  #define VIF_PARTS 31
  typedef struct{
    int   partitions;                /* 0 to 31 */
    int   partitionclass[VIF_PARTS]; /* 0 to 15 */
  
    int   class_dim[VIF_CLASS];        /* 1 to 8 */
    int   class_subs[VIF_CLASS];       /* 0,1,2,3 (bits: 1<<n poss) */
    int   class_book[VIF_CLASS];       /* subs ^ dim entries */
    int   class_subbook[VIF_CLASS][8]; /* [VIF_CLASS][subs] */
  
  
    int   mult;                      /* 1 2 3 or 4 */ 
    int   postlist[VIF_POSIT+2];    /* first two implicit */ 
  
  
    /* encode side analysis parameters */
    float maxover;     
    float maxunder;  
    float maxerr;    
  
    float twofitweight;  
    float twofitatten;
  
    int   n;
  
  } vorbis_info_floor1;
  
  /* Residue backend generic *****************************************/
  typedef struct{
    void                 (*pack)  (vorbis_info_residue *,oggpack_buffer *);
    vorbis_info_residue *(*unpack)(vorbis_info *,oggpack_buffer *);
    vorbis_look_residue *(*look)  (vorbis_dsp_state *,
  				 vorbis_info_residue *);
    void (*free_info)    (vorbis_info_residue *);
    void (*free_look)    (vorbis_look_residue *);
    long **(*class)      (struct vorbis_block *,vorbis_look_residue *,
  			float **,int *,int);
    int  (*forward)      (oggpack_buffer *,struct vorbis_block *,
  			vorbis_look_residue *,
  			float **,float **,int *,int,long **);
    int  (*inverse)      (struct vorbis_block *,vorbis_look_residue *,
  			float **,int *,int);
  } vorbis_func_residue;
  
  typedef struct vorbis_info_residue0{
  /* block-partitioned VQ coded straight residue */
    long  begin;
    long  end;
  
    /* first stage (lossless partitioning) */
    int    grouping;         /* group n vectors per partition */
    int    partitions;       /* possible codebooks for a partition */
    int    groupbook;        /* huffbook for partitioning */
    int    secondstages[64]; /* expanded out to pointers in lookup */
    int    booklist[256];    /* list of second stage books */
  
    float  classmetric1[64];  
    float  classmetric2[64];  
  
  } vorbis_info_residue0;
  
  /* Mapping backend generic *****************************************/
  typedef struct{
    void                 (*pack)  (vorbis_info *,vorbis_info_mapping *,
  				 oggpack_buffer *);
    vorbis_info_mapping *(*unpack)(vorbis_info *,oggpack_buffer *);
    void (*free_info)    (vorbis_info_mapping *);
    int  (*forward)      (struct vorbis_block *vb);
    int  (*inverse)      (struct vorbis_block *vb,vorbis_info_mapping *);
  } vorbis_func_mapping;
  
  typedef struct vorbis_info_mapping0{
    int   submaps;  /* <= 16 */
    int   chmuxlist[256];   /* up to 256 channels in a Vorbis stream */
    
    int   floorsubmap[16];   /* [mux] submap to floors */
    int   residuesubmap[16]; /* [mux] submap to residue */
  
    int   coupling_steps;
    int   coupling_mag[256];
    int   coupling_ang[256];
  
  } vorbis_info_mapping0;
  
  #endif
  
  
  