jpeg/jchuff.h
author Ehsan Akhgari <ehsan@mozilla.com>
Fri, 17 Dec 2010 20:45:18 -0800
changeset 61103 7294ab636e1d10985ac01d53ecbd1cd21e59b645
parent 1 9b2a99adc05e53cd4010de512f50118594756650
permissions -rw-r--r--
Bug 581536 - Part 3: Disconnect the transaction manager from the pres context as soon as it's disconnected from the pres shell; r=dbaron a=blocking-betaN+ This patch ensures that if for some reason, the pres context for a pres shell goes away, we do not hold on to the old transaction manager. Doing so would lead into the transition properties not being deleted from the elements, which will later on confuse the new transaction manager if we ever create one.

/*
 * jchuff.h
 *
 * Copyright (C) 1991-1997, 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.
 */

/* The legal range of a DCT coefficient is
 *  -1024 .. +1023  for 8-bit data;
 * -16384 .. +16383 for 12-bit data.
 * Hence the magnitude should always fit in 10 or 14 bits respectively.
 */

#if BITS_IN_JSAMPLE == 8
#define MAX_COEF_BITS 10
#else
#define MAX_COEF_BITS 14
#endif

/* 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, boolean isDC, int tblno,
	     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[]));