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/*
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 * jmorecfg.h
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 *
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 * Copyright (C) 1991-1997, Thomas G. Lane.
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 * This file is part of the Independent JPEG Group's software.
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 * For conditions of distribution and use, see the accompanying README file.
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 *
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 * This file contains additional configuration options that customize the
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 * JPEG software for special applications or support machine-dependent
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 * optimizations.  Most users will not need to touch this file.
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 */
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/*
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 * Define BITS_IN_JSAMPLE as either
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 *   8   for 8-bit sample values (the usual setting)
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 *   12  for 12-bit sample values
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 * Only 8 and 12 are legal data precisions for lossy JPEG according to the
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 * JPEG standard, and the IJG code does not support anything else!
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 * We do not support run-time selection of data precision, sorry.
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 */
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#define BITS_IN_JSAMPLE  8	/* use 8 or 12 */
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/*
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 * Maximum number of components (color channels) allowed in JPEG image.
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 * To meet the letter of the JPEG spec, set this to 255.  However, darn
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 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
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 * mask).  We recommend 10 as a reasonable compromise; use 4 if you are
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 * really short on memory.  (Each allowed component costs a hundred or so
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 * bytes of storage, whether actually used in an image or not.)
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 */
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#define MAX_COMPONENTS  10	/* maximum number of image components */
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/*
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 * Basic data types.
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 * You may need to change these if you have a machine with unusual data
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 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
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 * or "long" not 32 bits.  We don't care whether "int" is 16 or 32 bits,
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 * but it had better be at least 16.
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 */
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/* Representation of a single sample (pixel element value).
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 * We frequently allocate large arrays of these, so it's important to keep
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 * them small.  But if you have memory to burn and access to char or short
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 * arrays is very slow on your hardware, you might want to change these.
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 */
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#if BITS_IN_JSAMPLE == 8
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/* JSAMPLE should be the smallest type that will hold the values 0..255.
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 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
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 */
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#ifdef HAVE_UNSIGNED_CHAR
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typedef unsigned char JSAMPLE;
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#define GETJSAMPLE(value)  ((int) (value))
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#else /* not HAVE_UNSIGNED_CHAR */
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typedef char JSAMPLE;
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#ifdef CHAR_IS_UNSIGNED
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#define GETJSAMPLE(value)  ((int) (value))
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#else
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#define GETJSAMPLE(value)  ((int) (value) & 0xFF)
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#endif /* CHAR_IS_UNSIGNED */
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#endif /* HAVE_UNSIGNED_CHAR */
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#define MAXJSAMPLE	255
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#define CENTERJSAMPLE	128
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#endif /* BITS_IN_JSAMPLE == 8 */
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#if BITS_IN_JSAMPLE == 12
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/* JSAMPLE should be the smallest type that will hold the values 0..4095.
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 * On nearly all machines "short" will do nicely.
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 */
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typedef short JSAMPLE;
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#define GETJSAMPLE(value)  ((int) (value))
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#define MAXJSAMPLE	4095
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#define CENTERJSAMPLE	2048
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#endif /* BITS_IN_JSAMPLE == 12 */
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/* Representation of a DCT frequency coefficient.
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 * This should be a signed value of at least 16 bits; "short" is usually OK.
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 * Again, we allocate large arrays of these, but you can change to int
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 * if you have memory to burn and "short" is really slow.
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 */
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typedef short JCOEF;
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/* Compressed datastreams are represented as arrays of JOCTET.
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 * These must be EXACTLY 8 bits wide, at least once they are written to
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 * external storage.  Note that when using the stdio data source/destination
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 * managers, this is also the data type passed to fread/fwrite.
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 */
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#ifdef HAVE_UNSIGNED_CHAR
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typedef unsigned char JOCTET;
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#define GETJOCTET(value)  (value)
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#else /* not HAVE_UNSIGNED_CHAR */
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typedef char JOCTET;
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#ifdef CHAR_IS_UNSIGNED
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#define GETJOCTET(value)  (value)
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#else
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#define GETJOCTET(value)  ((value) & 0xFF)
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#endif /* CHAR_IS_UNSIGNED */
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#endif /* HAVE_UNSIGNED_CHAR */
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/* These typedefs are used for various table entries and so forth.
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 * They must be at least as wide as specified; but making them too big
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 * won't cost a huge amount of memory, so we don't provide special
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 * extraction code like we did for JSAMPLE.  (In other words, these
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 * typedefs live at a different point on the speed/space tradeoff curve.)
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 */
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/* UINT8 must hold at least the values 0..255. */
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#ifdef HAVE_UNSIGNED_CHAR
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typedef unsigned char UINT8;
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#else /* not HAVE_UNSIGNED_CHAR */
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#ifdef CHAR_IS_UNSIGNED
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typedef char UINT8;
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#else /* not CHAR_IS_UNSIGNED */
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typedef short UINT8;
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#endif /* CHAR_IS_UNSIGNED */
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#endif /* HAVE_UNSIGNED_CHAR */
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/* UINT16 must hold at least the values 0..65535. */
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#ifdef HAVE_UNSIGNED_SHORT
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typedef unsigned short UINT16;
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#else /* not HAVE_UNSIGNED_SHORT */
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typedef unsigned int UINT16;
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#endif /* HAVE_UNSIGNED_SHORT */
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/* INT16 must hold at least the values -32768..32767. */
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#ifndef XMD_H			/* X11/xmd.h correctly defines INT16 */
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typedef short INT16;
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#endif
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/* INT32 must hold at least signed 32-bit values. */
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#ifndef XMD_H			/* X11/xmd.h correctly defines INT32 */
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typedef long INT32;
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#endif
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/* Datatype used for image dimensions.  The JPEG standard only supports
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 * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
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 * "unsigned int" is sufficient on all machines.  However, if you need to
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 * handle larger images and you don't mind deviating from the spec, you
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 * can change this datatype.
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 */
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typedef unsigned int JDIMENSION;
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#define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */
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/* These macros are used in all function definitions and extern declarations.
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 * You could modify them if you need to change function linkage conventions;
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 * in particular, you'll need to do that to make the library a Windows DLL.
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 * Another application is to make all functions global for use with debuggers
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 * or code profilers that require it.
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 */
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/* a function called through method pointers: */
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#define METHODDEF(type)		static type
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/* a function used only in its module: */
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#define LOCAL(type)		static type
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/* a function referenced thru EXTERNs: */
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#define GLOBAL(type)		type
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/* a reference to a GLOBAL function: */
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#define EXTERN(type)		extern type
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/* This macro is used to declare a "method", that is, a function pointer.
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 * We want to supply prototype parameters if the compiler can cope.
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 * Note that the arglist parameter must be parenthesized!
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 * Again, you can customize this if you need special linkage keywords.
197
 */
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199
#ifdef HAVE_PROTOTYPES
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#define JMETHOD(type,methodname,arglist)  type (*methodname) arglist
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#else
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#define JMETHOD(type,methodname,arglist)  type (*methodname) ()
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#endif
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/* Here is the pseudo-keyword for declaring pointers that must be "far"
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 * on 80x86 machines.  Most of the specialized coding for 80x86 is handled
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 * by just saying "FAR *" where such a pointer is needed.  In a few places
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 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
210
 */
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212
#ifdef NEED_FAR_POINTERS
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#define FAR  far
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#else
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#define FAR
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#endif
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/*
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 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
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 * in standard header files.  Or you may have conflicts with application-
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 * specific header files that you want to include together with these files.
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 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
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 */
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#ifndef HAVE_BOOLEAN
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typedef int boolean;
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#endif
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#ifndef FALSE			/* in case these macros already exist */
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#define FALSE	0		/* values of boolean */
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#endif
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#ifndef TRUE
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#define TRUE	1
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#endif
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/*
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 * The remaining options affect code selection within the JPEG library,
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 * but they don't need to be visible to most applications using the library.
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 * To minimize application namespace pollution, the symbols won't be
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 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
242
 */
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244
#ifdef JPEG_INTERNALS
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#define JPEG_INTERNAL_OPTIONS
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#endif
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#ifdef JPEG_INTERNAL_OPTIONS
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/*
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 * These defines indicate whether to include various optional functions.
253
 * Undefining some of these symbols will produce a smaller but less capable
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 * library.  Note that you can leave certain source files out of the
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 * compilation/linking process if you've #undef'd the corresponding symbols.
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 * (You may HAVE to do that if your compiler doesn't like null source files.)
257
 */
258
 
259
/* Arithmetic coding is unsupported for legal reasons.  Complaints to IBM. */
260
 
261
/* Capability options common to encoder and decoder: */
262
 
263
#define DCT_ISLOW_SUPPORTED	/* slow but accurate integer algorithm */
264
#define DCT_IFAST_SUPPORTED	/* faster, less accurate integer method */
265
#define DCT_FLOAT_SUPPORTED	/* floating-point: accurate, fast on fast HW */
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/* Encoder capability options: */
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269
#undef  C_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
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#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
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#define C_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/
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#define ENTROPY_OPT_SUPPORTED	    /* Optimization of entropy coding parms? */
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/* Note: if you selected 12-bit data precision, it is dangerous to turn off
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 * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit
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 * precision, so jchuff.c normally uses entropy optimization to compute
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 * usable tables for higher precision.  If you don't want to do optimization,
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 * you'll have to supply different default Huffman tables.
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 * The exact same statements apply for progressive JPEG: the default tables
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 * don't work for progressive mode.  (This may get fixed, however.)
280
 */
281
#define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */
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283
/* Decoder capability options: */
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285
#undef  D_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
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#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
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#define D_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/
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#define SAVE_MARKERS_SUPPORTED	    /* jpeg_save_markers() needed? */
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#define BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */
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#define IDCT_SCALING_SUPPORTED	    /* Output rescaling via IDCT? */
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#undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */
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#define UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */
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#define QUANT_1PASS_SUPPORTED	    /* 1-pass color quantization? */
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#define QUANT_2PASS_SUPPORTED	    /* 2-pass color quantization? */
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296
/* more capability options later, no doubt */
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/*
300
 * Ordering of RGB data in scanlines passed to or from the application.
301
 * If your application wants to deal with data in the order B,G,R, just
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 * change these macros.  You can also deal with formats such as R,G,B,X
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 * (one extra byte per pixel) by changing RGB_PIXELSIZE.  Note that changing
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 * the offsets will also change the order in which colormap data is organized.
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 * RESTRICTIONS:
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 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
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 * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
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 *    useful if you are using JPEG color spaces other than YCbCr or grayscale.
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 * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
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 *    is not 3 (they don't understand about dummy color components!).  So you
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 *    can't use color quantization if you change that value.
312
 */
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314
#define RGB_RED		0	/* Offset of Red in an RGB scanline element */
315
#define RGB_GREEN	1	/* Offset of Green */
316
#define RGB_BLUE	2	/* Offset of Blue */
317
#define RGB_PIXELSIZE	3	/* JSAMPLEs per RGB scanline element */
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319
 
320
/* Definitions for speed-related optimizations. */
321
 
322
 
323
/* If your compiler supports inline functions, define INLINE
324
 * as the inline keyword; otherwise define it as empty.
325
 */
326
 
327
#ifndef INLINE
328
#ifdef __GNUC__			/* for instance, GNU C knows about inline */
329
#define INLINE __inline__
330
#endif
331
#ifndef INLINE
332
#define INLINE			/* default is to define it as empty */
333
#endif
334
#endif
335
 
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/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
338
 * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER
339
 * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.
340
 */
341
 
342
#ifndef MULTIPLIER
343
#define MULTIPLIER  int		/* type for fastest integer multiply */
344
#endif
345
 
346
 
347
/* FAST_FLOAT should be either float or double, whichever is done faster
348
 * by your compiler.  (Note that this type is only used in the floating point
349
 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
350
 * Typically, float is faster in ANSI C compilers, while double is faster in
351
 * pre-ANSI compilers (because they insist on converting to double anyway).
352
 * The code below therefore chooses float if we have ANSI-style prototypes.
353
 */
354
 
355
#ifndef FAST_FLOAT
356
#ifdef HAVE_PROTOTYPES
357
#define FAST_FLOAT  float
358
#else
359
#define FAST_FLOAT  double
360
#endif
361
#endif
362
 
363
#endif /* JPEG_INTERNAL_OPTIONS */