/************************************************************************** * * huffman.h -- Huffman coding functions * Copyright (C) 1994 Neil Sharman * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * **************************************************************************/ #ifndef H_HUFFMAN #define H_HUFFMAN #include #include "sysfuncs.h" #include "bitio_m_abstract.h" #define MAX_HUFFCODE_LEN 31 struct huff_data { int num_codes; int mincodelen; int maxcodelen; int lencount[MAX_HUFFCODE_LEN + 1]; unsigned long min_code[MAX_HUFFCODE_LEN + 1]; char *clens; }; huff_data *Generate_Huffman_Data (int num, long *freqs, huff_data * data, u_long * mem); unsigned long *Generate_Huffman_Codes (huff_data * data, u_long * mem); unsigned long **Generate_Huffman_Vals (huff_data * data, u_long * mem); int Write_Huffman_Data (FILE * f, huff_data * hd); int Read_Huffman_Data (FILE * f, huff_data * hd, u_long * mem, u_long * disk); /* Calculate the number of bits required to code the data with the specified frequencies. Normally freqs and counts should point to the same array. */ double Calculate_Huffman_Size (int num, long *freqs, long *counts); #endif