vorbis/lib/codebook.h

/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
 * THE GNU LESSER/LIBRARY PUBLIC LICENSE, WHICH IS INCLUDED WITH    *
 * THIS SOURCE. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.        *
 *                                                                  *
 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2000             *
 * by Monty <monty@xiph.org> and the XIPHOPHORUS Company            *
 * http://www.xiph.org/                                             *
 *                                                                  *
 ********************************************************************

 function: basic shared codebook operations
 last mod: $Id: codebook.h,v 1.1.2.2 2000/11/04 06:21:43 xiphmont Exp $

 ********************************************************************/

#ifndef _V_CODEBOOK_H_
#define _V_CODEBOOK_H_

/* This structure encapsulates huffman and VQ style encoding books; it
   doesn't do anything specific to either.

   valuelist/quantlist are nonNULL (and q_* significant) only if
   there's entry->value mapping to be done.

   If encode-side mapping must be done (and thus the entry needs to be
   hunted), the auxiliary encode pointer will point to a decision
   tree.  This is true of both VQ and huffman, but is mostly useful
   with VQ.

*/

typedef struct static_codebook{
  long   dim;            /* codebook dimensions (elements per vector) */
  long   entries;        /* codebook entries */
  long  *lengthlist;     /* codeword lengths in bits */

  /* mapping ***************************************************************/
  int    maptype;        /* 0=none
			    1=implicitly populated values from map column 
			    2=listed arbitrary values */

  /* The below does a linear, single monotonic sequence mapping. */
  long     q_min;       /* packed 32 bit float; quant value 0 maps to minval */
  long     q_delta;     /* packed 32 bit float; val 1 - val 0 == delta */
  int      q_quant;     /* bits: 0 < quant <= 16 */
  int      q_sequencep; /* bitflag */

  long     *quantlist;  /* map == 1: (int)(entries^(1/dim)) element column map
			   map == 2: list of dim*entries quantized entry vals
			*/

  /* encode helpers ********************************************************/
  struct encode_aux_nearestmatch *nearest_tree;
  struct encode_aux_threshmatch  *thresh_tree;
  struct encode_aux_pigeonhole  *pigeon_tree;

  int allocedp;
} static_codebook;

/* this structures an arbitrary trained book to quickly find the
   nearest cell match */
typedef struct encode_aux_nearestmatch{
  /* pre-calculated partitioning tree */
  long   *ptr0;
  long   *ptr1;

  long   *p;         /* decision points (each is an entry) */
  long   *q;         /* decision points (each is an entry) */
  long   aux;        /* number of tree entries */
  long   alloc;       
} encode_aux_nearestmatch;

/* assumes a maptype of 1; encode side only, so that's OK */
typedef struct encode_aux_threshmatch{
  float *quantthresh;
  long   *quantmap;
  int     quantvals; 
  int     threshvals; 
} encode_aux_threshmatch;

typedef struct encode_aux_pigeonhole{
  float min;
  float del;

  int  mapentries;
  int  quantvals;
  long *pigeonmap;

  long fittotal;
  long *fitlist;
  long *fitmap;
  long *fitlength;
} encode_aux_pigeonhole;

typedef struct decode_aux{
  long   *tab;
  int    *tabl;
  int    tabn;

  long   *ptr0;
  long   *ptr1;
  long   aux;        /* number of tree entries */
} decode_aux;

typedef struct codebook{
  long dim;           /* codebook dimensions (elements per vector) */
  long entries;       /* codebook entries */
  const static_codebook *c;

  float  *valuelist;  /* list of dim*entries actual entry values */
  long   *codelist;   /* list of bitstream codewords for each entry */
  struct decode_aux *decode_tree;

} codebook;

extern void vorbis_staticbook_clear(static_codebook *b);
extern void vorbis_staticbook_destroy(static_codebook *b);
extern int vorbis_book_init_encode(codebook *dest,const static_codebook *source);
extern int vorbis_book_init_decode(codebook *dest,const static_codebook *source);
extern void vorbis_book_clear(codebook *b);

extern float *_book_unquantize(const static_codebook *b);
extern float *_book_logdist(const static_codebook *b,float *vals);
extern float _float32_unpack(long val);
extern long   _float32_pack(float val);
extern int  _best(codebook *book, float *a, int step);
extern int _ilog(unsigned int v);
extern long _book_maptype1_quantvals(const static_codebook *b);

extern int vorbis_book_besterror(codebook *book,float *a,int step,int addmul);
extern long vorbis_book_codeword(codebook *book,int entry);
extern long vorbis_book_codelen(codebook *book,int entry);



extern int vorbis_staticbook_pack(const static_codebook *c,oggpack_buffer *b);
extern int vorbis_staticbook_unpack(oggpack_buffer *b,static_codebook *c);

extern int vorbis_book_encode(codebook *book, int a, oggpack_buffer *b);
extern int vorbis_book_errorv(codebook *book, float *a);
extern int vorbis_book_encodev(codebook *book, int best,float *a, 
			       oggpack_buffer *b);
extern int vorbis_book_encodevs(codebook *book, float *a, oggpack_buffer *b,
				int step,int stagetype);

extern long vorbis_book_decode(codebook *book, oggpack_buffer *b);
extern long vorbis_book_decodevs(codebook *book, float *a, oggpack_buffer *b,
				 int step,int stagetype);
extern long s_vorbis_book_decodevs(codebook *book, float *a, oggpack_buffer *b,
				   int step,int stagetype);



#endif