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