1/* 2 * Copyright 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef IMG_UTILS_TIFF_HELPERS_H 18#define IMG_UTILS_TIFF_HELPERS_H 19 20#include <stdint.h> 21 22namespace android { 23namespace img_utils { 24 25const uint8_t ZERO_WORD[] = {0, 0, 0, 0}; 26 27#define BAIL_ON_FAIL(x, flag) \ 28 if (((flag) = (x)) != OK) return flag; 29 30#define BYTES_TILL_WORD(index) \ 31 ((TIFF_WORD_SIZE - ((index) % TIFF_WORD_SIZE)) % TIFF_WORD_SIZE) 32 33#define WORD_ALIGN(count) \ 34 count += BYTES_TILL_WORD(count); 35 36#define ZERO_TILL_WORD(output, index, ret) \ 37 { \ 38 size_t remaining = BYTES_TILL_WORD(index); \ 39 if (remaining > 0) { \ 40 BAIL_ON_FAIL((output)->write(ZERO_WORD, 0, remaining), ret); \ 41 } \ 42 } 43 44/** 45 * Basic TIFF header constants. 46 */ 47enum { 48 BAD_OFFSET = 0, 49 TIFF_WORD_SIZE = 4, // Size in bytes 50 IFD_HEADER_SIZE = 2, // Size in bytes 51 IFD_FOOTER_SIZE = 4, // Size in bytes 52 TIFF_ENTRY_SIZE = 12, // Size in bytes 53 MAX_IFD_ENTRIES = UINT16_MAX, 54 FILE_HEADER_SIZE = 8, // Size in bytes 55 ENDIAN_MARKER_SIZE = 2, // Size in bytes 56 TIFF_MARKER_SIZE = 2, // Size in bytes 57 OFFSET_MARKER_SIZE = 4, // Size in bytes 58 TIFF_FILE_MARKER = 42, 59 BIG_ENDIAN_MARKER = 0x4D4Du, 60 LITTLE_ENDIAN_MARKER = 0x4949u 61}; 62 63/** 64 * Constants for the TIFF tag types. 65 */ 66enum TagType { 67 UNKNOWN_TAGTYPE = 0, 68 BYTE=1, 69 ASCII, 70 SHORT, 71 LONG, 72 RATIONAL, 73 SBYTE, 74 UNDEFINED, 75 SSHORT, 76 SLONG, 77 SRATIONAL, 78 FLOAT, 79 DOUBLE 80}; 81 82/** 83 * Sizes of the TIFF entry fields (in bytes). 84 */ 85enum { 86 TAG_SIZE = 2, 87 TYPE_SIZE = 2, 88 COUNT_SIZE = 4, 89 OFFSET_SIZE = 4 90}; 91 92/** 93 * Convenience IFD id constants. 94 */ 95enum { 96 IFD_0 = 0, 97 RAW_IFD, 98 PROFILE_IFD, 99 PREVIEW_IFD 100}; 101 102inline size_t getTypeSize(TagType type) { 103 switch(type) { 104 case UNDEFINED: 105 case ASCII: 106 case BYTE: 107 case SBYTE: 108 return 1; 109 case SHORT: 110 case SSHORT: 111 return 2; 112 case LONG: 113 case SLONG: 114 case FLOAT: 115 return 4; 116 case RATIONAL: 117 case SRATIONAL: 118 case DOUBLE: 119 return 8; 120 default: 121 return 0; 122 } 123} 124 125inline uint32_t calculateIfdSize(size_t numberOfEntries) { 126 return IFD_HEADER_SIZE + IFD_FOOTER_SIZE + TIFF_ENTRY_SIZE * numberOfEntries; 127} 128 129} /*namespace img_utils*/ 130} /*namespace android*/ 131 132#endif /*IMG_UTILS_TIFF_HELPERS_H*/ 133