HUFF.h File Reference

Huffman Encode/Decode, interface file. More...

#include <PBI/Endianness.h>

Classes
struct	_HUFF_code
	Structure to contain the Huffman code, both the bit pattern and its length. More...
struct	_HUFF_symbol_bf
	The information associate with a decoded symbol. More...
union	_HUFF_symbol
Defines
#define	HUFF_N_WA(_cnt)   (HUFF_N_HEAP(_cnt) + HUFF_N_PARENTS(_cnt))
	Gives the number of 32-bit elements needed by the temporary wa array based of the number of elements in the frequency table.
Typedefs
typedef struct _HUFF_dtable	HUFF_dtable
typedef struct _HUFF_code	HUFF_code
	Typedef for struct _HUFF_code.
typedef struct _HUFF_symbol_bf	HUFF_symbol_bf
typedef union _HUFF_symbol	HUFF_symbol
Functions
int	HUFF_build (HUFF_code *codes, const unsigned int *freqs, int count, unsigned int *wa)
int	HUFF_buildDense (HUFF_code *codes, const unsigned int *freq, const unsigned int *valid, int nvalid, unsigned int *wa)
int	HUFF_buildSparse (HUFF_code *codes, const unsigned int *freq, const unsigned int *valid, int nvalid, unsigned int *wa)
int	HUFF_bcompress (void *out, unsigned int boff, void *max, const HUFF_code *codes, const unsigned char *in, int cnt, int *unencoded)
int	HUFF_size (const HUFF_code *codes, const unsigned int *freqs, int count)
int	HUFF_sizeDense (const HUFF_code *codes, const unsigned int *freq, const unsigned int *valid, int nvalid)
int	HUFF_sizeSparse (const HUFF_code *codes, const unsigned int *freq, const unsigned int *valid, int nvalid)
int	HUFF_dtableSizeof (int nsymbols)
void	HUFF_dtableBuild (HUFF_dtable *dtable, const unsigned char *sym_lens, int nsymbols)
void	HUFF_dtableBiase (HUFF_dtable *dtable, int biase)
void	HUFF_dtablePrint (const HUFF_dtable *dtable)
unsigned int	HUFF_decode (const HUFF_dtable *dtable, const unsigned int *src, unsigned int boff)
int	HUFF_decompressBytes (unsigned char *dst, int cnt, const void *src, unsigned int boff, const HUFF_dtable *dtable)
int	HUFF_decompressShorts (unsigned short int *dst, int cnt, const void *src, unsigned int boff, const HUFF_dtable *dtable)
int	HUFF_decompressLongs (unsigned int *dst, int cnt, const void *src, unsigned int boff, const HUFF_dtable *dtable)
void	HUFF_codesPrint (const HUFF_code *codes, int ncodes)

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Detailed Description

Huffman Encode/Decode, interface file.

Author:

JJRussell - russell@slac.stanford.edu

CVS $Id

Warning:

In their current state, these routines are not fit for Flight use. They can be used to determine compression factors and, in general, study the properties of Huffman encoding/decoding. However, they malloc all over the place and involve recursive calling techniques, neither of is appropriate for Flight code.

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Define Documentation

#define HUFF_N_WA

(

_cnt

)

(HUFF_N_HEAP(_cnt) + HUFF_N_PARENTS(_cnt))

Gives the number of 32-bit elements needed by the temporary wa array based of the number of elements in the frequency table.

Returns:

The number of elements needed by the temporary wa array

Parameters:

_cnt

The number of 32-bit elements in the frequency table.