www.pudn.com > jpeglib.rar > JCHUFF.h

//////////////////////////////////////////////////////////////////////// 
// 
//	Note : this file is included as part of the Smaller Animals Software 
//	JpegFile package. Though this file has not been modified from it's  
//	original IJG 6a form, it is not the responsibility on the Independent 
//	JPEG Group to answer questions regarding this code. 
//	 
//	Any questions you have about this code should be addressed to : 
// 
//	CHRISDL@PAGESZ.NET	- the distributor of this package. 
// 
//	Remember, by including this code in the JpegFile package, Smaller  
//	Animals Software assumes all responsibilities for answering questions 
//	about it. If we (SA Software) can't answer your questions ourselves, we  
//	will direct you to people who can. 
// 
//	Thanks, CDL. 
// 
//////////////////////////////////////////////////////////////////////// 
/* 
 * jchuff.h 
 * 
 * Copyright (C) 1991-1996, 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[]));