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/* $Id: lzw.h,v 1.2 1997/05/14 00:40:58 per Exp $ */ 
 
#define GIF_LZW 
 
#ifdef GIF_LZW 
typedef unsigned short lzwcode_t; /* no more than 12 bits used */ 
#else 
typedef unsigned long lzwcode_t; 
#endif 
 
struct lzw 
{ 
   unsigned long codes; 
   unsigned long bits; /* initial encoding bits */ 
   unsigned long codebits; /* current encoding bits */ 
   unsigned long outlen,outpos,outbit; 
   unsigned char *out,lastout; 
   struct lzwc  
   { 
      unsigned char c; 
      lzwcode_t firstchild; 
      lzwcode_t next; 
   } *code; 
   lzwcode_t current,firstfree; 
#ifndef GIF_LZW 
   unsigned long alloced; 
#endif 
}; 
 
#define LZWCNULL ((lzwcode_t)(~0)) 
 
void lzw_add(struct lzw *lzw,int c); 
void lzw_quit(struct lzw *lzw); 
void lzw_init(struct lzw *lzw,int bits); 
void lzw_write_last(struct lzw *lzw); 
unsigned long lzw_unpack(unsigned char *dest,unsigned long destlen, 
                         unsigned char *src,unsigned long srclen, 
                         int bits);