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_IFD_H 18 #define IMG_UTILS_TIFF_IFD_H 19 20 #include <img_utils/TiffWritable.h> 21 #include <img_utils/TiffEntry.h> 22 #include <img_utils/Output.h> 23 #include <img_utils/SortedEntryVector.h> 24 25 #include <cutils/compiler.h> 26 #include <utils/Errors.h> 27 #include <utils/String8.h> 28 #include <utils/SortedVector.h> 29 #include <utils/StrongPointer.h> 30 #include <stdint.h> 31 32 namespace android { 33 namespace img_utils { 34 35 /** 36 * This class holds a single TIFF Image File Directory (IFD) structure. 37 * 38 * This maps to the TIFF IFD structure that is logically composed of: 39 * - A 2-byte field listing the number of entries. 40 * - A list of 12-byte TIFF entries. 41 * - A 4-byte offset to the next IFD. 42 */ 43 class ANDROID_API TiffIfd : public TiffWritable { 44 public: 45 TiffIfd(uint32_t ifdId); 46 virtual ~TiffIfd(); 47 48 /** 49 * Add a TiffEntry to this IFD or replace an existing entry with the 50 * same tag ID. No validation is done. 51 * 52 * Returns OK on success, or a negative error code on failure. 53 */ 54 virtual status_t addEntry(const sp<TiffEntry>& entry); 55 56 /** 57 * Set the pointer to the next IFD. This is used to create a linked 58 * list of IFDs as defined by the TIFF 6.0 spec., and is not included 59 * when calculating the size of IFD and entries for the getSize() 60 * method (unlike SubIFDs). 61 */ 62 virtual void setNextIfd(const sp<TiffIfd>& ifd); 63 64 /** 65 * Get the pointer to the next IFD, or NULL if none exists. 66 */ 67 virtual sp<TiffIfd> getNextIfd() const; 68 69 /** 70 * Write the IFD data. This includes the IFD header, entries, footer, 71 * and the corresponding values for each entry (recursively including 72 * sub-IFDs). The written amount should end on a word boundary, and 73 * the given offset should be word aligned. 74 * 75 * Returns OK on success, or a negative error code on failure. 76 */ 77 virtual status_t writeData(uint32_t offset, /*out*/EndianOutput* out) const; 78 79 /** 80 * Get the size of the IFD. This includes the IFD header, entries, footer, 81 * and the corresponding values for each entry (recursively including 82 * any sub-IFDs). 83 */ 84 virtual size_t getSize() const; 85 86 /** 87 * Get the id of this IFD. 88 */ 89 virtual uint32_t getId() const; 90 91 /** 92 * Get an entry with the given tag ID. 93 * 94 * Returns a strong pointer to the entry if it exists, or an empty strong 95 * pointer. 96 */ 97 virtual sp<TiffEntry> getEntry(uint16_t tag) const; 98 99 /** 100 * Remove the entry with the given tag ID if it exists. 101 */ 102 virtual void removeEntry(uint16_t tag); 103 104 /** 105 * Convenience method to validate and set strip-related image tags. 106 * 107 * This sets all strip related tags, but leaves offset values unitialized. 108 * setStripOffsets must be called with the desired offset before writing. 109 * The strip tag values are calculated from the existing tags for image 110 * dimensions and pixel type set in the IFD. 111 * 112 * Does not handle planar image configurations (PlanarConfiguration != 1). 113 * 114 * Returns OK on success, or a negative error code. 115 */ 116 virtual status_t validateAndSetStripTags(); 117 118 /** 119 * Returns true if validateAndSetStripTags has been called, but not setStripOffsets. 120 */ 121 virtual bool uninitializedOffsets() const; 122 123 /** 124 * Convenience method to set beginning offset for strips. 125 * 126 * Call this to update the strip offsets before calling writeData. 127 * 128 * Returns OK on success, or a negative error code. 129 */ 130 virtual status_t setStripOffset(uint32_t offset); 131 132 /** 133 * Get the total size of the strips in bytes. 134 * 135 * This sums the byte count at each strip offset, and returns 136 * the total count of bytes stored in strips for this IFD. 137 */ 138 virtual uint32_t getStripSize() const; 139 140 /** 141 * Get a formatted string representing this IFD. 142 */ 143 virtual String8 toString() const; 144 145 /** 146 * Print a formatted string representing this IFD to logcat. 147 */ 148 void log() const; 149 150 /** 151 * Get value used to determine sort order. 152 */ 153 virtual uint32_t getComparableValue() const; 154 155 protected: 156 virtual uint32_t checkAndGetOffset(uint32_t offset) const; 157 SortedEntryVector mEntries; 158 sp<TiffIfd> mNextIfd; 159 uint32_t mIfdId; 160 bool mStripOffsetsInitialized; 161 }; 162 163 } /*namespace img_utils*/ 164 } /*namespace android*/ 165 166 #endif /*IMG_UTILS_TIFF_IFD_H*/ 167
