The Tor Browser: media/libjpeg/jmorecfg.h@b8a032363ba2 (annotated)

media/libjpeg/jmorecfg.h@b8a032363ba2 (annotated)

media/libjpeg/jmorecfg.h

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  * 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 */

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media/libjpeg/jmorecfg.h@b8a032363ba2 (annotated)

media/libjpeg/jmorecfg.h