Play Audio Files with DirectSound and Display its Spectrum in Real Time - Part 3

/********************************************************************
 *                                                                  *
 * 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 1994-2007             *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: basic shared codebook operations
 last mod: $Id: codebook.h 13293 2007-07-24 00:09:47Z xiphmont $

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

#ifndef _V_CODEBOOK_H_
#define _V_CODEBOOK_H_

#include <ogg/ogg.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 codebook{
  long dim;           /* codebook dimensions (elements per vector) */
  long entries;       /* codebook entries */
  long used_entries;  /* populated codebook entries */
  const static_codebook *c;

  /* for encode, the below are entry-ordered, fully populated */
  /* for decode, the below are ordered by bitreversed codeword and only
     used entries are populated */
  float        *valuelist;  /* list of dim*entries actual entry values */  
  ogg_uint32_t *codelist;   /* list of bitstream codewords for each entry */

  int          *dec_index;  /* only used if sparseness collapsed */
  char         *dec_codelengths;
  ogg_uint32_t *dec_firsttable;
  int           dec_firsttablen;
  int           dec_maxlength;

} 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,int n,int *map);
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 long vorbis_book_decode(codebook *book, oggpack_buffer *b);
extern long vorbis_book_decodevs_add(codebook *book, float *a, 
				     oggpack_buffer *b,int n);
extern long vorbis_book_decodev_set(codebook *book, float *a, 
				    oggpack_buffer *b,int n);
extern long vorbis_book_decodev_add(codebook *book, float *a, 
				    oggpack_buffer *b,int n);
extern long vorbis_book_decodevv_add(codebook *book, float **a,
				     long off,int ch, 
				    oggpack_buffer *b,int n);



#endif