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/* Copyright (C) 1994 Aladdin Enterprises. All rights reserved.
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This software is provided AS-IS with no warranty, either express or
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implied.
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This software is distributed under license and may not be copied,
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modified or distributed except as expressly authorized under the terms
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of the license contained in the file LICENSE in this distribution.
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For more information about licensing, please refer to
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http://www.ghostscript.com/licensing/. For information on
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commercial licensing, go to http://www.artifex.com/licensing/ or
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contact Artifex Software, Inc., 101 Lucas Valley Road #110,
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San Rafael, CA 94903, U.S.A., +1(415)492-9861.
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*/
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/* $Id: shcgen.h,v 1.5 2002/06/16 05:00:54 lpd Exp $ */
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/* Interface for Huffman code generation */
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/* Requires shc.h */
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#ifndef shcgen_INCLUDED
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# define shcgen_INCLUDED
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/* Compute an optimal Huffman code from an input data set. */
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/* The client must have set all the elements of *def. */
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/* The definition is guaranteed to be well-behaved. */
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int hc_compute(hc_definition * def, const long *freqs, gs_memory_t * mem);
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/* Convert a definition to a byte string. */
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/* The caller must provide the byte string, of length def->num_values. */
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/* Assume (do not check) that the definition is well-behaved. */
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/* Return the actual length of the string. */
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int hc_bytes_from_definition(byte * dbytes, const hc_definition * def);
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/* Extract num_counts and num_values from a byte string. */
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void hc_sizes_from_bytes(hc_definition * def, const byte * dbytes, int num_bytes);
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/* Convert a byte string back to a definition. */
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/* The caller must initialize *def, including allocating counts and values. */
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void hc_definition_from_bytes(hc_definition * def, const byte * dbytes);
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/* Generate the encoding table from the definition. */
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/* The size of the encode array is def->num_values. */
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void hc_make_encoding(hce_code * encode, const hc_definition * def);
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/* Calculate the size of the decoding table. */
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uint hc_sizeof_decoding(const hc_definition * def, int initial_bits);
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/* Generate the decoding tables. */
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void hc_make_decoding(hcd_code * decode, const hc_definition * def,
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int initial_bits);
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#endif /* shcgen_INCLUDED */
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