tif_swab.c 9.46 KB
Newer Older
wester committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310
/* $Id: tif_swab.c,v 1.13 2010-03-10 18:56:49 bfriesen Exp $ */

/*
 * Copyright (c) 1988-1997 Sam Leffler
 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 *
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

/*
 * TIFF Library Bit & Byte Swapping Support.
 *
 * XXX We assume short = 16-bits and long = 32-bits XXX
 */
#include "tiffiop.h"

#ifndef TIFFSwabShort
void
TIFFSwabShort(uint16* wp)
{
    register unsigned char* cp = (unsigned char*) wp;
    unsigned char t;
    assert(sizeof(uint16)==2);
    t = cp[1]; cp[1] = cp[0]; cp[0] = t;
}
#endif

#ifndef TIFFSwabLong
void
TIFFSwabLong(uint32* lp)
{
    register unsigned char* cp = (unsigned char*) lp;
    unsigned char t;
    assert(sizeof(uint32)==4);
    t = cp[3]; cp[3] = cp[0]; cp[0] = t;
    t = cp[2]; cp[2] = cp[1]; cp[1] = t;
}
#endif

#ifndef TIFFSwabLong8
void
TIFFSwabLong8(uint64* lp)
{
    register unsigned char* cp = (unsigned char*) lp;
    unsigned char t;
    assert(sizeof(uint64)==8);
    t = cp[7]; cp[7] = cp[0]; cp[0] = t;
    t = cp[6]; cp[6] = cp[1]; cp[1] = t;
    t = cp[5]; cp[5] = cp[2]; cp[2] = t;
    t = cp[4]; cp[4] = cp[3]; cp[3] = t;
}
#endif

#ifndef TIFFSwabArrayOfShort
void
TIFFSwabArrayOfShort(register uint16* wp, tmsize_t n)
{
    register unsigned char* cp;
    register unsigned char t;
    assert(sizeof(uint16)==2);
    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char*) wp;
        t = cp[1]; cp[1] = cp[0]; cp[0] = t;
        wp++;
    }
}
#endif

#ifndef TIFFSwabArrayOfTriples
void
TIFFSwabArrayOfTriples(register uint8* tp, tmsize_t n)
{
    unsigned char* cp;
    unsigned char t;

    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char*) tp;
        t = cp[2]; cp[2] = cp[0]; cp[0] = t;
        tp += 3;
    }
}
#endif

#ifndef TIFFSwabArrayOfLong
void
TIFFSwabArrayOfLong(register uint32* lp, tmsize_t n)
{
    register unsigned char *cp;
    register unsigned char t;
    assert(sizeof(uint32)==4);
    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char *)lp;
        t = cp[3]; cp[3] = cp[0]; cp[0] = t;
        t = cp[2]; cp[2] = cp[1]; cp[1] = t;
        lp++;
    }
}
#endif

#ifndef TIFFSwabArrayOfLong8
void
TIFFSwabArrayOfLong8(register uint64* lp, tmsize_t n)
{
    register unsigned char *cp;
    register unsigned char t;
    assert(sizeof(uint64)==8);
    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char *)lp;
        t = cp[7]; cp[7] = cp[0]; cp[0] = t;
        t = cp[6]; cp[6] = cp[1]; cp[1] = t;
        t = cp[5]; cp[5] = cp[2]; cp[2] = t;
        t = cp[4]; cp[4] = cp[3]; cp[3] = t;
        lp++;
    }
}
#endif

#ifndef TIFFSwabFloat
void
TIFFSwabFloat(float* fp)
{
    register unsigned char* cp = (unsigned char*) fp;
    unsigned char t;
    assert(sizeof(float)==4);
    t = cp[3]; cp[3] = cp[0]; cp[0] = t;
    t = cp[2]; cp[2] = cp[1]; cp[1] = t;
}
#endif

#ifndef TIFFSwabArrayOfFloat
void
TIFFSwabArrayOfFloat(register float* fp, tmsize_t n)
{
    register unsigned char *cp;
    register unsigned char t;
    assert(sizeof(float)==4);
    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char *)fp;
        t = cp[3]; cp[3] = cp[0]; cp[0] = t;
        t = cp[2]; cp[2] = cp[1]; cp[1] = t;
        fp++;
    }
}
#endif

#ifndef TIFFSwabDouble
void
TIFFSwabDouble(double *dp)
{
    register unsigned char* cp = (unsigned char*) dp;
    unsigned char t;
    assert(sizeof(double)==8);
    t = cp[7]; cp[7] = cp[0]; cp[0] = t;
    t = cp[6]; cp[6] = cp[1]; cp[1] = t;
    t = cp[5]; cp[5] = cp[2]; cp[2] = t;
    t = cp[4]; cp[4] = cp[3]; cp[3] = t;
}
#endif

#ifndef TIFFSwabArrayOfDouble
void
TIFFSwabArrayOfDouble(double* dp, tmsize_t n)
{
    register unsigned char *cp;
    register unsigned char t;
    assert(sizeof(double)==8);
    /* XXX unroll loop some */
    while (n-- > 0) {
        cp = (unsigned char *)dp;
        t = cp[7]; cp[7] = cp[0]; cp[0] = t;
        t = cp[6]; cp[6] = cp[1]; cp[1] = t;
        t = cp[5]; cp[5] = cp[2]; cp[2] = t;
        t = cp[4]; cp[4] = cp[3]; cp[3] = t;
        dp++;
    }
}
#endif

/*
 * Bit reversal tables.  TIFFBitRevTable[<byte>] gives
 * the bit reversed value of <byte>.  Used in various
 * places in the library when the FillOrder requires
 * bit reversal of byte values (e.g. CCITT Fax 3
 * encoding/decoding).  TIFFNoBitRevTable is provided
 * for algorithms that want an equivalent table that
 * do not reverse bit values.
 */
static const unsigned char TIFFBitRevTable[256] = {
    0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
    0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
    0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
    0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
    0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
    0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
    0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
    0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
    0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
    0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
    0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
    0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
    0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
    0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
    0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
    0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
    0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
    0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
    0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
    0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
    0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
    0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
    0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
    0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
    0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
    0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
    0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
    0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
    0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
    0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
    0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
    0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
};
static const unsigned char TIFFNoBitRevTable[256] = {
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
    0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
    0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
    0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
    0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
    0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
    0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
    0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
    0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
    0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
    0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
    0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
    0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
    0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
    0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
    0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
    0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
    0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
    0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
    0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
    0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
    0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
    0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
    0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
    0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
};

const unsigned char*
TIFFGetBitRevTable(int reversed)
{
    return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable);
}

void
TIFFReverseBits(uint8* cp, tmsize_t n)
{
    for (; n > 8; n -= 8) {
        cp[0] = TIFFBitRevTable[cp[0]];
        cp[1] = TIFFBitRevTable[cp[1]];
        cp[2] = TIFFBitRevTable[cp[2]];
        cp[3] = TIFFBitRevTable[cp[3]];
        cp[4] = TIFFBitRevTable[cp[4]];
        cp[5] = TIFFBitRevTable[cp[5]];
        cp[6] = TIFFBitRevTable[cp[6]];
        cp[7] = TIFFBitRevTable[cp[7]];
        cp += 8;
    }
    while (n-- > 0)
        *cp = TIFFBitRevTable[*cp], cp++;
}

/* vim: set ts=8 sts=8 sw=8 noet: */
/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 8
 * fill-column: 78
 * End:
 */