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