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1 // Copyright 2015 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 ////////////////////////////////////////////////////////////////////////////////
16 
17 #ifndef PIEX_TIFF_PARSER_H_
18 #define PIEX_TIFF_PARSER_H_
19 
20 #include <cstdint>
21 #include <memory>
22 #include <set>
23 #include <vector>
24 
25 #include "src/piex_types.h"
26 #include "src/tiff_directory/tiff_directory.h"
27 
28 namespace piex {
29 
30 // Specifies the maximum number of pixels for thumbnails in each direction.
31 const int kThumbnailMaxDimension = 512;
32 
33 // Specifies all tags that might be of interest to get the preview data.
34 enum GpsTags {
35   kGpsTagLatitudeRef = 1,
36   kGpsTagLatitude = 2,
37   kGpsTagLongitudeRef = 3,
38   kGpsTagLongitude = 4,
39   kGpsTagAltitudeRef = 5,
40   kGpsTagAltitude = 6,
41   kGpsTagTimeStamp = 7,
42   kGpsTagDateStamp = 29,
43 };
44 
45 enum TiffTags {
46   kExifTagColorSpace = 0xA001,
47   kExifTagDateTimeOriginal = 0x9003,
48   kExifTagDefaultCropSize = 0xC620,
49   kExifTagExposureTime = 0x829a,
50   kExifTagFnumber = 0x829d,
51   kExifTagFocalLength = 0x920A,
52   kExifTagGps = 0x8825,
53   kExifTagHeight = 0xA003,
54   kExifTagIsoSpeed = 0x8827,
55   kExifTagMakernotes = 0x927C,
56   kExifTagWidth = 0xA002,
57   kOlymTagAspectFrame = 0x1113,
58   kOlymTagCameraSettings = 0x2020,
59   kOlymTagRawProcessing = 0x2040,
60   kPanaTagBottomBorder = 0x006,
61   kPanaTagIso = 0x0017,
62   kPanaTagJpegImage = 0x002E,
63   kPanaTagLeftBorder = 0x0005,
64   kPanaTagRightBorder = 0x007,
65   kPanaTagTopBorder = 0x0004,
66   kPentaxTagColorSpace = 0x0037,
67   kTiffTagArtist = 0x013B,
68   kTiffTagBitsPerSample = 0x0102,
69   kTiffTagCfaPatternDim = 0x828D,
70   kTiffTagCompression = 0x0103,
71   kTiffTagDateTime = 0x0132,
72   kTiffTagExifIfd = 0x8769,
73   kTiffTagImageDescription = 0x010E,
74   kTiffTagImageLength = 0x0101,
75   kTiffTagImageWidth = 0x0100,
76   kTiffTagJpegByteCount = 0x0202,
77   kTiffTagJpegOffset = 0x0201,
78   kTiffTagMake = 0x010F,
79   kTiffTagModel = 0x0110,
80   kTiffTagOrientation = 0x0112,
81   kTiffTagPhotometric = 0x0106,
82   kTiffTagPlanarConfig = 0x011C,
83   kTiffTagResolutionUnit = 0x0128,
84   kTiffTagRowsPerStrip = 0x0116,
85   kTiffTagSamplesPerPixel = 0x0115,
86   kTiffTagSoftware = 0x0131,
87   kTiffTagStripByteCounts = 0x0117,
88   kTiffTagStripOffsets = 0x0111,
89   kTiffTagSubFileType = 0x00FE,
90   kTiffTagSubIfd = 0x014A,
91   kTiffTagTileByteCounts = 0x0145,
92   kTiffTagTileLength = 0x0143,
93   kTiffTagTileOffsets = 0x0144,
94   kTiffTagTileWidth = 0x0142,
95   kTiffTagXresolution = 0x011A,
96   kTiffTagYresolution = 0x011B,
97 };
98 
99 typedef std::set<tiff_directory::TiffDirectory::Tag> TagSet;
100 typedef std::vector<tiff_directory::TiffDirectory> IfdVector;
101 
102 struct TiffContent {
103   IfdVector tiff_directory;
104   std::unique_ptr<tiff_directory::TiffDirectory> exif_directory;
105   std::unique_ptr<tiff_directory::TiffDirectory> gps_directory;
106 };
107 
108 // Reads 2 bytes, an unsigned 16bit from 'stream' at a certain 'offset'. The
109 // bytes get swapped according to the desired endianness returning true on
110 // success. Returns false when something is wrong.
111 bool Get16u(StreamInterface* stream, const std::uint32_t offset,
112             const tiff_directory::Endian& endian, std::uint16_t* value);
113 
114 // Reads 4 bytes, an unsigned 32bit 'value' from 'stream' at a certain 'offset'.
115 // The bytes get swapped according to the desired endianness returning true on
116 // success. Returns false when something is wrong.
117 bool Get32u(StreamInterface* stream, const std::uint32_t offset,
118             const tiff_directory::Endian& endian, std::uint32_t* value);
119 
120 // Retrieves a byte vector of size 'length' from 'stream' beginning at some
121 // 'offset' reading the data in chunks of one MiB.
122 // If 'error' is not set to kOk the returned value is invalid.
123 std::vector<std::uint8_t> GetData(const size_t offset, const size_t length,
124                                   StreamInterface* stream, Error* error);
125 
126 // Retrieves the endianness of TIFF compliant data at 'tiff_offset' from
127 // 'stream' returning true on success. Returns false when something is wrong.
128 bool GetEndianness(const std::uint32_t tiff_offset, StreamInterface* stream,
129                    tiff_directory::Endian* endian);
130 
131 // Retrieves an image from tiff_directory. Return false when something is wrong.
132 bool GetImageData(const tiff_directory::TiffDirectory& tiff_directory,
133                   StreamInterface* stream, Image* image);
134 
135 // Retrieves the width and height from the jpeg image returning true on
136 // success. Returns false when something is wrong.
137 bool GetJpegDimensions(const std::uint32_t jpeg_offset, StreamInterface* stream,
138                        std::uint16_t* width, std::uint16_t* height);
139 
140 // According to Tiff/EP a thumbnail has max 256 pixels per dimension.
141 // http://standardsproposals.bsigroup.com/Home/getPDF/567
142 bool IsThumbnail(const Image& image,
143                  const int max_dimension = kThumbnailMaxDimension);
144 
145 // Parses through a Tiff IFD and writes all 'desired_tags' to a
146 // 'tiff_directory'.
147 // Returns false if something with the Tiff data is wrong.
148 bool ParseDirectory(const std::uint32_t tiff_offset,
149                     const std::uint32_t ifd_offset,
150                     const tiff_directory::Endian endian,
151                     const TagSet& desired_tags, StreamInterface* stream,
152                     tiff_directory::TiffDirectory* tiff_directory,
153                     std::uint32_t* next_ifd_offset);
154 
155 // Returns true if Exif orientation for the image can be obtained. False
156 // otherwise.
157 bool GetExifOrientation(StreamInterface* stream, const std::uint32_t offset,
158                         std::uint32_t* orientation);
159 
160 // Reads the width and height of the full resolution image. The tag groups are
161 // exclusive.
162 bool GetFullDimension32(const tiff_directory::TiffDirectory& tiff_directory,
163                         std::uint32_t* width, std::uint32_t* height);
164 
165 // Reads the width and height of the crop information if available.
166 // Returns false if an error occurred.
167 bool GetFullCropDimension(const tiff_directory::TiffDirectory& tiff_directory,
168                           std::uint32_t* width, std::uint32_t* height);
169 
170 // Reads 1 or more rational values for a tag and stores results into data.
171 // Returns false if an error occurred.
172 bool GetRational(const tiff_directory::TiffDirectory::Tag& tag,
173                  const tiff_directory::TiffDirectory& directory,
174                  const int data_size, PreviewImageData::Rational* data);
175 
176 // Enables us to parse through data that complies to the Tiff/EP specification.
177 class TiffParser {
178  public:
179   // The caller owns 'stream' and is responsible to keep it alive while the
180   // TiffParser object is used.
181   explicit TiffParser(StreamInterface* stream);
182   TiffParser(StreamInterface* stream, const std::uint32_t offset);
183 
184   // Runs over the Tiff IFD, Exif IFD and subIFDs to get the preview image data.
185   // Returns false if something with the Tiff tags is wrong.
186   bool GetPreviewImageData(const TiffContent& tiff_content,
187                            PreviewImageData* preview_image_data);
188 
189   // Returns false if called more that once or something with the Tiff data is
190   // wrong.
191   bool Parse(const TagSet& desired_tags, const std::uint16_t max_number_ifds,
192              TiffContent* tiff_content);
193 
194  private:
195   // Disallow copy and assignment.
196   TiffParser(const TiffParser&) = delete;
197   TiffParser& operator=(const TiffParser&) = delete;
198 
199   bool ParseIfd(const std::uint32_t ifd_offset, const TagSet& desired_tags,
200                 const std::uint16_t max_number_ifds, IfdVector* tiff_directory);
201   bool ParseGpsData(const tiff_directory::TiffDirectory* tiff_ifd,
202                     TiffContent* tiff_content);
203 
204   StreamInterface* stream_ = nullptr;
205   std::uint32_t tiff_offset_ = 0;
206   tiff_directory::Endian endian_;
207 };
208 
209 }  // namespace piex
210 
211 #endif  // PIEX_TIFF_PARSER_H_
212