1/* $Id: tif_swab.c,v 1.4.2.1 2010-06-08 18:50:43 bfriesen Exp $ */ 2 3/* 4 * Copyright (c) 1988-1997 Sam Leffler 5 * Copyright (c) 1991-1997 Silicon Graphics, Inc. 6 * 7 * Permission to use, copy, modify, distribute, and sell this software and 8 * its documentation for any purpose is hereby granted without fee, provided 9 * that (i) the above copyright notices and this permission notice appear in 10 * all copies of the software and related documentation, and (ii) the names of 11 * Sam Leffler and Silicon Graphics may not be used in any advertising or 12 * publicity relating to the software without the specific, prior written 13 * permission of Sam Leffler and Silicon Graphics. 14 * 15 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 17 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 18 * 19 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR 20 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, 21 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, 22 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 23 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 24 * OF THIS SOFTWARE. 25 */ 26 27/* 28 * TIFF Library Bit & Byte Swapping Support. 29 * 30 * XXX We assume short = 16-bits and long = 32-bits XXX 31 */ 32#include "tiffiop.h" 33 34#ifndef TIFFSwabShort 35void 36TIFFSwabShort(uint16* wp) 37{ 38 register unsigned char* cp = (unsigned char*) wp; 39 unsigned char t; 40 41 t = cp[1]; cp[1] = cp[0]; cp[0] = t; 42} 43#endif 44 45#ifndef TIFFSwabLong 46void 47TIFFSwabLong(uint32* lp) 48{ 49 register unsigned char* cp = (unsigned char*) lp; 50 unsigned char t; 51 52 t = cp[3]; cp[3] = cp[0]; cp[0] = t; 53 t = cp[2]; cp[2] = cp[1]; cp[1] = t; 54} 55#endif 56 57#ifndef TIFFSwabArrayOfShort 58void 59TIFFSwabArrayOfShort(uint16* wp, register unsigned long n) 60{ 61 register unsigned char* cp; 62 register unsigned char t; 63 64 /* XXX unroll loop some */ 65 while (n-- > 0) { 66 cp = (unsigned char*) wp; 67 t = cp[1]; cp[1] = cp[0]; cp[0] = t; 68 wp++; 69 } 70} 71#endif 72 73#ifndef TIFFSwabArrayOfTriples 74void 75TIFFSwabArrayOfTriples(uint8* tp, unsigned long n) 76{ 77 unsigned char* cp; 78 unsigned char t; 79 80 /* XXX unroll loop some */ 81 while (n-- > 0) { 82 cp = (unsigned char*) tp; 83 t = cp[2]; cp[2] = cp[0]; cp[0] = t; 84 tp += 3; 85 } 86} 87#endif 88 89#ifndef TIFFSwabArrayOfLong 90void 91TIFFSwabArrayOfLong(register uint32* lp, register unsigned long n) 92{ 93 register unsigned char *cp; 94 register unsigned char t; 95 96 /* XXX unroll loop some */ 97 while (n-- > 0) { 98 cp = (unsigned char *)lp; 99 t = cp[3]; cp[3] = cp[0]; cp[0] = t; 100 t = cp[2]; cp[2] = cp[1]; cp[1] = t; 101 lp++; 102 } 103} 104#endif 105 106#ifndef TIFFSwabDouble 107void 108TIFFSwabDouble(double *dp) 109{ 110 register uint32* lp = (uint32*) dp; 111 uint32 t; 112 113 TIFFSwabArrayOfLong(lp, 2); 114 t = lp[0]; lp[0] = lp[1]; lp[1] = t; 115} 116#endif 117 118#ifndef TIFFSwabArrayOfDouble 119void 120TIFFSwabArrayOfDouble(double* dp, register unsigned long n) 121{ 122 register uint32* lp = (uint32*) dp; 123 register uint32 t; 124 125 TIFFSwabArrayOfLong(lp, n + n); 126 while (n-- > 0) { 127 t = lp[0]; lp[0] = lp[1]; lp[1] = t; 128 lp += 2; 129 } 130} 131#endif 132 133/* 134 * Bit reversal tables. TIFFBitRevTable[<byte>] gives 135 * the bit reversed value of <byte>. Used in various 136 * places in the library when the FillOrder requires 137 * bit reversal of byte values (e.g. CCITT Fax 3 138 * encoding/decoding). TIFFNoBitRevTable is provided 139 * for algorithms that want an equivalent table that 140 * do not reverse bit values. 141 */ 142static const unsigned char TIFFBitRevTable[256] = { 143 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 144 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, 145 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, 146 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, 147 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 148 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, 149 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 150 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, 151 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 152 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, 153 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, 154 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, 155 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 156 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, 157 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 158 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, 159 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, 160 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, 161 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 162 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, 163 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, 164 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, 165 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 166 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, 167 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 168 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, 169 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 170 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, 171 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, 172 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, 173 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 174 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff 175}; 176static const unsigned char TIFFNoBitRevTable[256] = { 177 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 178 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 179 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 180 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 181 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 182 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 183 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 184 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 185 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 186 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 187 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 188 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 189 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 190 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 191 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 192 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 193 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 194 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 195 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 196 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 197 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 198 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 199 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 200 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 201 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 202 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 203 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 204 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 205 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 206 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 207 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 208 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 209}; 210 211const unsigned char* 212TIFFGetBitRevTable(int reversed) 213{ 214 return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable); 215} 216 217void 218TIFFReverseBits(register unsigned char* cp, register unsigned long n) 219{ 220 for (; n > 8; n -= 8) { 221 cp[0] = TIFFBitRevTable[cp[0]]; 222 cp[1] = TIFFBitRevTable[cp[1]]; 223 cp[2] = TIFFBitRevTable[cp[2]]; 224 cp[3] = TIFFBitRevTable[cp[3]]; 225 cp[4] = TIFFBitRevTable[cp[4]]; 226 cp[5] = TIFFBitRevTable[cp[5]]; 227 cp[6] = TIFFBitRevTable[cp[6]]; 228 cp[7] = TIFFBitRevTable[cp[7]]; 229 cp += 8; 230 } 231 while (n-- > 0) 232 *cp = TIFFBitRevTable[*cp], cp++; 233} 234 235/* vim: set ts=8 sts=8 sw=8 noet: */ 236/* 237 * Local Variables: 238 * mode: c 239 * c-basic-offset: 8 240 * fill-column: 78 241 * End: 242 */ 243