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      1 /*
      2  * jmorecfg.h
      3  *
      4  * Copyright (C) 1991-1997, Thomas G. Lane.
      5  * This file is part of the Independent JPEG Group's software.
      6  * For conditions of distribution and use, see the accompanying README file.
      7  *
      8  * This file contains additional configuration options that customize the
      9  * JPEG software for special applications or support machine-dependent
     10  * optimizations.  Most users will not need to touch this file.
     11  */
     12 
     13 #ifndef JMORECFG_H
     14 #define JMORECFG_H
     15 
     16 #include <stdint.h>
     17 
     18 /*
     19  * Define ANDROID_RGB to enable specific optimizations for Android
     20  *   JCS_RGBA_8888 support
     21  *   JCS_RGB_565 support
     22  *
     23  */
     24 
     25 #define ANDROID_RGB
     26 
     27 #ifdef ANDROID_RGB
     28 #define PACK_SHORT_565(r,g,b)  ((((r)<<8)&0xf800)|(((g)<<3)&0x7E0)|((b)>>3))
     29 #define PACK_TWO_PIXELS(l,r)   ((r<<16) | l)
     30 #define PACK_NEED_ALIGNMENT(ptr) (((uintptr_t)(ptr))&3)
     31 #define WRITE_TWO_PIXELS(addr, pixels) do {     \
     32          ((INT16*)(addr))[0] = (pixels);        \
     33          ((INT16*)(addr))[1] = (pixels)>>16;    \
     34     } while(0)
     35 #define WRITE_TWO_ALIGNED_PIXELS(addr, pixels)  ((*(INT32*)(addr)) = pixels)
     36 #define DITHER_565_R(r, dither) ((r) + ((dither)&0xFF))
     37 #define DITHER_565_G(g, dither) ((g) + (((dither)&0xFF)>>1))
     38 #define DITHER_565_B(b, dither) ((b) + ((dither)&0xFF))
     39 #endif
     40 
     41 /*
     42  * Define BITS_IN_JSAMPLE as either
     43  *   8   for 8-bit sample values (the usual setting)
     44  *   12  for 12-bit sample values
     45  * Only 8 and 12 are legal data precisions for lossy JPEG according to the
     46  * JPEG standard, and the IJG code does not support anything else!
     47  * We do not support run-time selection of data precision, sorry.
     48  */
     49 
     50 #define BITS_IN_JSAMPLE  8	/* use 8 or 12 */
     51 
     52 
     53 /*
     54  * Maximum number of components (color channels) allowed in JPEG image.
     55  * To meet the letter of the JPEG spec, set this to 255.  However, darn
     56  * few applications need more than 4 channels (maybe 5 for CMYK + alpha
     57  * mask).  We recommend 10 as a reasonable compromise; use 4 if you are
     58  * really short on memory.  (Each allowed component costs a hundred or so
     59  * bytes of storage, whether actually used in an image or not.)
     60  */
     61 
     62 #define MAX_COMPONENTS  10	/* maximum number of image components */
     63 
     64 
     65 /*
     66  * Basic data types.
     67  * You may need to change these if you have a machine with unusual data
     68  * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
     69  * or "long" not 32 bits.  We don't care whether "int" is 16 or 32 bits,
     70  * but it had better be at least 16.
     71  */
     72 
     73 /* Representation of a single sample (pixel element value).
     74  * We frequently allocate large arrays of these, so it's important to keep
     75  * them small.  But if you have memory to burn and access to char or short
     76  * arrays is very slow on your hardware, you might want to change these.
     77  */
     78 
     79 #if BITS_IN_JSAMPLE == 8
     80 /* JSAMPLE should be the smallest type that will hold the values 0..255.
     81  * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
     82  */
     83 
     84 #ifdef HAVE_UNSIGNED_CHAR
     85 
     86 typedef uint8_t JSAMPLE;
     87 #define GETJSAMPLE(value)  ((int) (value))
     88 
     89 #else /* not HAVE_UNSIGNED_CHAR */
     90 
     91 typedef char JSAMPLE;
     92 #ifdef CHAR_IS_UNSIGNED
     93 #define GETJSAMPLE(value)  ((int) (value))
     94 #else
     95 #define GETJSAMPLE(value)  ((int) (value) & 0xFF)
     96 #endif /* CHAR_IS_UNSIGNED */
     97 
     98 #endif /* HAVE_UNSIGNED_CHAR */
     99 
    100 #define MAXJSAMPLE	255
    101 #define CENTERJSAMPLE	128
    102 
    103 #endif /* BITS_IN_JSAMPLE == 8 */
    104 
    105 
    106 #if BITS_IN_JSAMPLE == 12
    107 /* JSAMPLE should be the smallest type that will hold the values 0..4095.
    108  * On nearly all machines "short" will do nicely.
    109  */
    110 
    111 typedef int16_t JSAMPLE;
    112 #define GETJSAMPLE(value)  ((int) (value))
    113 
    114 #define MAXJSAMPLE	4095
    115 #define CENTERJSAMPLE	2048
    116 
    117 #endif /* BITS_IN_JSAMPLE == 12 */
    118 
    119 
    120 /* Representation of a DCT frequency coefficient.
    121  * This should be a signed value of at least 16 bits; "short" is usually OK.
    122  * Again, we allocate large arrays of these, but you can change to int
    123  * if you have memory to burn and "short" is really slow.
    124  */
    125 
    126 typedef int16_t JCOEF;
    127 
    128 
    129 /* Compressed datastreams are represented as arrays of JOCTET.
    130  * These must be EXACTLY 8 bits wide, at least once they are written to
    131  * external storage.  Note that when using the stdio data source/destination
    132  * managers, this is also the data type passed to fread/fwrite.
    133  */
    134 
    135 #ifdef HAVE_UNSIGNED_CHAR
    136 
    137 typedef uint8_t JOCTET;
    138 #define GETJOCTET(value)  (value)
    139 
    140 #else /* not HAVE_UNSIGNED_CHAR */
    141 
    142 typedef char JOCTET;
    143 #ifdef CHAR_IS_UNSIGNED
    144 #define GETJOCTET(value)  (value)
    145 #else
    146 #define GETJOCTET(value)  ((value) & 0xFF)
    147 #endif /* CHAR_IS_UNSIGNED */
    148 
    149 #endif /* HAVE_UNSIGNED_CHAR */
    150 
    151 
    152 /* These typedefs are used for various table entries and so forth.
    153  * They must be at least as wide as specified; but making them too big
    154  * won't cost a huge amount of memory, so we don't provide special
    155  * extraction code like we did for JSAMPLE.  (In other words, these
    156  * typedefs live at a different point on the speed/space tradeoff curve.)
    157  */
    158 
    159 /* UINT8 must hold at least the values 0..255. */
    160 
    161 #ifdef HAVE_UNSIGNED_CHAR
    162 typedef uint8_t UINT8;
    163 #else /* not HAVE_UNSIGNED_CHAR */
    164 #ifdef CHAR_IS_UNSIGNED
    165 typedef char UINT8;
    166 #else /* not CHAR_IS_UNSIGNED */
    167 typedef short UINT8;
    168 #endif /* CHAR_IS_UNSIGNED */
    169 #endif /* HAVE_UNSIGNED_CHAR */
    170 
    171 /* UINT16 must hold at least the values 0..65535. */
    172 
    173 #ifdef HAVE_UNSIGNED_SHORT
    174 typedef uint16_t UINT16;
    175 #else /* not HAVE_UNSIGNED_SHORT */
    176 typedef unsigned int UINT16;
    177 #endif /* HAVE_UNSIGNED_SHORT */
    178 
    179 /* INT16 must hold at least the values -32768..32767. */
    180 
    181 #ifndef XMD_H			/* X11/xmd.h correctly defines INT16 */
    182 typedef int16_t INT16;
    183 #endif
    184 
    185 /* INT32 must hold at least signed 32-bit values. */
    186 
    187 #ifndef XMD_H			/* X11/xmd.h correctly defines INT32 */
    188 typedef int32_t INT32;
    189 #endif
    190 
    191 /* Datatype used for image dimensions.  The JPEG standard only supports
    192  * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
    193  * "unsigned int" is sufficient on all machines.  However, if you need to
    194  * handle larger images and you don't mind deviating from the spec, you
    195  * can change this datatype.
    196  */
    197 
    198 typedef unsigned int JDIMENSION;
    199 
    200 #define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */
    201 
    202 
    203 /* These macros are used in all function definitions and extern declarations.
    204  * You could modify them if you need to change function linkage conventions;
    205  * in particular, you'll need to do that to make the library a Windows DLL.
    206  * Another application is to make all functions global for use with debuggers
    207  * or code profilers that require it.
    208  */
    209 
    210 /* a function called through method pointers: */
    211 #define METHODDEF(type)		static type
    212 /* a function used only in its module: */
    213 #define LOCAL(type)		static type
    214 /* a function referenced thru EXTERNs: */
    215 #define GLOBAL(type)		type
    216 /* a reference to a GLOBAL function: */
    217 #define EXTERN(type)		extern type
    218 
    219 
    220 /* This macro is used to declare a "method", that is, a function pointer.
    221  * We want to supply prototype parameters if the compiler can cope.
    222  * Note that the arglist parameter must be parenthesized!
    223  * Again, you can customize this if you need special linkage keywords.
    224  */
    225 
    226 #ifdef HAVE_PROTOTYPES
    227 #define JMETHOD(type,methodname,arglist)  type (*methodname) arglist
    228 #else
    229 #define JMETHOD(type,methodname,arglist)  type (*methodname) ()
    230 #endif
    231 
    232 
    233 /* Here is the pseudo-keyword for declaring pointers that must be "far"
    234  * on 80x86 machines.  Most of the specialized coding for 80x86 is handled
    235  * by just saying "FAR *" where such a pointer is needed.  In a few places
    236  * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
    237  */
    238 
    239 #ifdef NEED_FAR_POINTERS
    240 #define FAR  far
    241 #else
    242 #define FAR
    243 #endif
    244 
    245 
    246 /*
    247  * On a few systems, type boolean and/or its values FALSE, TRUE may appear
    248  * in standard header files.  Or you may have conflicts with application-
    249  * specific header files that you want to include together with these files.
    250  * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
    251  */
    252 
    253 #ifndef HAVE_BOOLEAN
    254 typedef int boolean;
    255 #endif
    256 #ifndef FALSE			/* in case these macros already exist */
    257 #define FALSE	0		/* values of boolean */
    258 #endif
    259 #ifndef TRUE
    260 #define TRUE	1
    261 #endif
    262 
    263 
    264 /*
    265  * The remaining options affect code selection within the JPEG library,
    266  * but they don't need to be visible to most applications using the library.
    267  * To minimize application namespace pollution, the symbols won't be
    268  * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
    269  */
    270 
    271 #ifdef JPEG_INTERNALS
    272 #define JPEG_INTERNAL_OPTIONS
    273 #endif
    274 
    275 #ifdef JPEG_INTERNAL_OPTIONS
    276 
    277 
    278 /*
    279  * These defines indicate whether to include various optional functions.
    280  * Undefining some of these symbols will produce a smaller but less capable
    281  * library.  Note that you can leave certain source files out of the
    282  * compilation/linking process if you've #undef'd the corresponding symbols.
    283  * (You may HAVE to do that if your compiler doesn't like null source files.)
    284  */
    285 
    286 /* Arithmetic coding is unsupported for legal reasons.  Complaints to IBM. */
    287 
    288 /* Capability options common to encoder and decoder: */
    289 
    290 #define DCT_ISLOW_SUPPORTED	/* slow but accurate integer algorithm */
    291 #define DCT_IFAST_SUPPORTED	/* faster, less accurate integer method */
    292 #define DCT_FLOAT_SUPPORTED	/* floating-point: accurate, fast on fast HW */
    293 
    294 /* Encoder capability options: */
    295 
    296 #undef  C_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
    297 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
    298 #define C_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/
    299 #define ENTROPY_OPT_SUPPORTED	    /* Optimization of entropy coding parms? */
    300 /* Note: if you selected 12-bit data precision, it is dangerous to turn off
    301  * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit
    302  * precision, so jchuff.c normally uses entropy optimization to compute
    303  * usable tables for higher precision.  If you don't want to do optimization,
    304  * you'll have to supply different default Huffman tables.
    305  * The exact same statements apply for progressive JPEG: the default tables
    306  * don't work for progressive mode.  (This may get fixed, however.)
    307  */
    308 #define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */
    309 
    310 /* Decoder capability options: */
    311 
    312 #undef  D_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
    313 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
    314 #define D_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/
    315 #define SAVE_MARKERS_SUPPORTED	    /* jpeg_save_markers() needed? */
    316 #define BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */
    317 #define IDCT_SCALING_SUPPORTED	    /* Output rescaling via IDCT? */
    318 #undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */
    319 #define UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */
    320 #define QUANT_1PASS_SUPPORTED	    /* 1-pass color quantization? */
    321 #define QUANT_2PASS_SUPPORTED	    /* 2-pass color quantization? */
    322 
    323 /* more capability options later, no doubt */
    324 
    325 
    326 /*
    327  * Ordering of RGB data in scanlines passed to or from the application.
    328  * If your application wants to deal with data in the order B,G,R, just
    329  * change these macros.  You can also deal with formats such as R,G,B,X
    330  * (one extra byte per pixel) by changing RGB_PIXELSIZE.  Note that changing
    331  * the offsets will also change the order in which colormap data is organized.
    332  * RESTRICTIONS:
    333  * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
    334  * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
    335  *    useful if you are using JPEG color spaces other than YCbCr or grayscale.
    336  * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
    337  *    is not 3 (they don't understand about dummy color components!).  So you
    338  *    can't use color quantization if you change that value.
    339  */
    340 
    341 #define RGB_RED		0	/* Offset of Red in an RGB scanline element */
    342 #define RGB_GREEN	1	/* Offset of Green */
    343 #define RGB_BLUE	2	/* Offset of Blue */
    344 #ifdef ANDROID_RGB
    345 #define RGB_ALPHA   3   /* Offset of Alpha */
    346 #endif
    347 #define RGB_PIXELSIZE   3   /* JSAMPLEs per RGB scanline element */
    348 
    349 /* Definitions for speed-related optimizations. */
    350 
    351 
    352 /* If your compiler supports inline functions, define INLINE
    353  * as the inline keyword; otherwise define it as empty.
    354  */
    355 
    356 #ifndef INLINE
    357 #ifdef __GNUC__			/* for instance, GNU C knows about inline */
    358 #define INLINE __inline__
    359 #endif
    360 #ifndef INLINE
    361 #define INLINE			/* default is to define it as empty */
    362 #endif
    363 #endif
    364 
    365 
    366 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
    367  * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER
    368  * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.
    369  */
    370 
    371 #ifndef MULTIPLIER
    372 #ifdef ANDROID_INTELSSE2_IDCT
    373   #define MULTIPLIER short
    374 #elif ANDROID_MIPS_IDCT
    375   #define MULTIPLIER  short
    376 #elif NV_ARM_NEON
    377   #define MULTIPLIER short
    378 #else
    379   #define MULTIPLIER  int		/* type for fastest integer multiply */
    380 #endif
    381 #endif
    382 
    383 
    384 /* FAST_FLOAT should be either float or double, whichever is done faster
    385  * by your compiler.  (Note that this type is only used in the floating point
    386  * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
    387  * Typically, float is faster in ANSI C compilers, while double is faster in
    388  * pre-ANSI compilers (because they insist on converting to double anyway).
    389  * The code below therefore chooses float if we have ANSI-style prototypes.
    390  */
    391 
    392 #ifndef FAST_FLOAT
    393 #ifdef HAVE_PROTOTYPES
    394 #define FAST_FLOAT  float
    395 #else
    396 #define FAST_FLOAT  double
    397 #endif
    398 #endif
    399 
    400 #endif /* JPEG_INTERNAL_OPTIONS */
    401 
    402 #endif /* JMORECFG_H */
    403