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 /*

  * jmorecfg.h

  *

  * This file was part of the Independent JPEG Group's software:

  * Copyright (C) 1991-1997, Thomas G. Lane.

  * Modifications:

  * Copyright (C) 2009, 2011, D. R. Commander.

  * 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.

  */

 #include <stdint.h>

 /*

  * 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_UNSIGNED__

 #define GETJSAMPLE(value)  ((int) (value))

 #else

 #define GETJSAMPLE(value)  ((int) (value) & 0xFF)

 #endif /* __CHAR_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_UNSIGNED__

 #define GETJOCTET(value)  (value)

 #else

 #define GETJOCTET(value)  ((value) & 0xFF)

 #endif /* __CHAR_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. */

 typedef uint8_t UINT8;

 /* UINT16 must hold at least the values 0..65535. */

 typedef uint16_t UINT16;

 /* INT16 must hold at least the values -32768..32767. */

 typedef int16_t INT16;

 /* INT32 must hold at least signed 32-bit values. */

 typedef int32_t INT32;

 /* 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

 #ifndef FAR

 #define FAR  far

 #endif

 #else

 #undef FAR

 #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.)

  */

 /* 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: */

 #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: */

 #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 */

 #define JPEG_NUMCS 16

 #define EXT_RGB_RED        0

 #define EXT_RGB_GREEN      1

 #define EXT_RGB_BLUE       2

 #define EXT_RGB_PIXELSIZE  3

 #define EXT_RGBX_RED       0

 #define EXT_RGBX_GREEN     1

 #define EXT_RGBX_BLUE      2

 #define EXT_RGBX_PIXELSIZE 4

 #define EXT_BGR_RED        2

 #define EXT_BGR_GREEN      1

 #define EXT_BGR_BLUE       0

 #define EXT_BGR_PIXELSIZE  3

 #define EXT_BGRX_RED       2

 #define EXT_BGRX_GREEN     1

 #define EXT_BGRX_BLUE      0

 #define EXT_BGRX_PIXELSIZE 4

 #define EXT_XBGR_RED       3

 #define EXT_XBGR_GREEN     2

 #define EXT_XBGR_BLUE      1

 #define EXT_XBGR_PIXELSIZE 4

 #define EXT_XRGB_RED       1

 #define EXT_XRGB_GREEN     2

 #define EXT_XRGB_BLUE      3

 #define EXT_XRGB_PIXELSIZE 4

 static const int rgb_red[JPEG_NUMCS] = {

   -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED,

   EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,

   EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED

 };

 static const int rgb_green[JPEG_NUMCS] = {

   -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN,

   EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,

   EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN

 };

 static const int rgb_blue[JPEG_NUMCS] = {

   -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE,

   EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,

   EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE

 };

 static const int rgb_pixelsize[JPEG_NUMCS] = {

   -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE,

   EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE,

   EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE

 };

 /* Definitions for speed-related optimizations. */

 /* 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

 #ifndef WITH_SIMD

 #define MULTIPLIER  int		/* type for fastest integer multiply */

 #else

 #define MULTIPLIER short  /* prefer 16-bit with SIMD for parellelism */

 #endif

 #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 */