| /* |
| * 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[])); |