ref: bea7b7bf8ccbc2bc41906517079e76fcfb31cb5a
dir: /code/jpeg-6/jchuff.h/
/*
* jchuff.h
*
* Copyright (C) 1991-1995, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains declarations for Huffman entropy encoding routines
* that are shared between the sequential encoder (jchuff.c) and the
* progressive encoder (jcphuff.c). No other modules need to see these.
*/
/* Derived data constructed for each Huffman table */
typedef struct {
unsigned int ehufco[256]; /* code for each symbol */
char ehufsi[256]; /* length of code for each symbol */
/* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */
} c_derived_tbl;
/* Short forms of external names for systems with brain-damaged linkers. */
#ifdef NEED_SHORT_EXTERNAL_NAMES
#define jpeg_make_c_derived_tbl jMkCDerived
#define jpeg_gen_optimal_table jGenOptTbl
#endif /* NEED_SHORT_EXTERNAL_NAMES */
/* Expand a Huffman table definition into the derived format */
EXTERN void jpeg_make_c_derived_tbl JPP((j_compress_ptr cinfo,
JHUFF_TBL * htbl, c_derived_tbl ** pdtbl));
/* Generate an optimal table definition given the specified counts */
EXTERN void jpeg_gen_optimal_table JPP((j_compress_ptr cinfo,
JHUFF_TBL * htbl, long freq[]));