• backends.h
  • /********************************************************************
     *                                                                  *
     * 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 1994-2009             *
     * by the Xiph.Org Foundation https://xiph.org/                     *
     *                                                                  *
     ********************************************************************
    
     function: libvorbis backend and mapping structures; needed for
               static mode headers
    
     ********************************************************************/
    
    /* 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 *,
                            int **,int *,int);
      int  (*forward)      (oggpack_buffer *,struct vorbis_block *,
                            vorbis_look_residue *,
                            int **,int *,int,long **,int);
      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    partvals;         /* partitions ^ groupbook dim */
      int    groupbook;        /* huffbook for partitioning */
      int    secondstages[64]; /* expanded out to pointers in lookup */
      int    booklist[512];    /* list of second stage books */
    
      const int classmetric1[64];
      const int 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