1 // ***************************************************************** -*- C++ -*-
2 /*
3 * Copyright (C) 2004-2021 Exiv2 authors
4 * This program is part of the Exiv2 distribution.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301 USA.
19 */
20 // xmpsample.cpp
21 // Sample/test for high level XMP classes. See also addmoddel.cpp
22
23 #include <exiv2/exiv2.hpp>
24 #include "unused.h"
25
26 #include <string>
27 #include <iostream>
28 #include <iomanip>
29 #include <cassert>
30 #include <cmath>
31
isEqual(float a,float b)32 bool isEqual(float a, float b)
33 {
34 double d = std::fabs(a - b);
35 return d < 0.00001;
36 }
37
main()38 int main()
39 try {
40 Exiv2::XmpParser::initialize();
41 ::atexit(Exiv2::XmpParser::terminate);
42 #ifdef EXV_ENABLE_BMFF
43 Exiv2::enableBMFF();
44 #endif
45
46 // The XMP property container
47 Exiv2::XmpData xmpData;
48
49 // -------------------------------------------------------------------------
50 // Teaser: Setting XMP properties doesn't get much easier than this:
51
52 xmpData["Xmp.dc.source"] = "xmpsample.cpp"; // a simple text value
53 xmpData["Xmp.dc.subject"] = "Palmtree"; // an array item
54 xmpData["Xmp.dc.subject"] = "Rubbertree"; // add a 2nd array item
55 // a language alternative with two entries and without default
56 xmpData["Xmp.dc.title"] = "lang=de-DE Sonnenuntergang am Strand";
57 xmpData["Xmp.dc.title"] = "lang=en-US Sunset on the beach";
58
59 // -------------------------------------------------------------------------
60 // Any properties can be set provided the namespace is known. Values of any
61 // type can be assigned to an Xmpdatum, if they have an output operator. The
62 // default XMP value type for unknown properties is a simple text value.
63
64 xmpData["Xmp.dc.one"] = -1;
65 xmpData["Xmp.dc.two"] = 3.1415;
66 xmpData["Xmp.dc.three"] = Exiv2::Rational(5, 7);
67 xmpData["Xmp.dc.four"] = uint16_t(255);
68 xmpData["Xmp.dc.five"] = 256;
69 xmpData["Xmp.dc.six"] = false;
70
71 // In addition, there is a dedicated assignment operator for Exiv2::Value
72 Exiv2::XmpTextValue val("Seven");
73 xmpData["Xmp.dc.seven"] = val;
74 xmpData["Xmp.dc.eight"] = true;
75
76 // Extracting values
77 assert(xmpData["Xmp.dc.one"].toLong() == -1);
78 assert(xmpData["Xmp.dc.one"].value().ok());
79
80 const Exiv2::Value &getv1 = xmpData["Xmp.dc.one"].value();
81 UNUSED(getv1);
82 assert(isEqual(getv1.toFloat(), -1));
83 assert(getv1.ok());
84 assert(getv1.toRational() == Exiv2::Rational(-1, 1));
85 assert(getv1.ok());
86
87 const Exiv2::Value &getv2 = xmpData["Xmp.dc.two"].value();
88 UNUSED(getv2);
89 assert(isEqual(getv2.toFloat(), 3.1415f));
90 assert(getv2.ok());
91 assert(getv2.toLong() == 3);
92 assert(getv2.ok());
93 Exiv2::Rational R = getv2.toRational();
94 UNUSED(R);
95 assert(getv2.ok());
96 assert(isEqual(static_cast<float>(R.first) / R.second, 3.1415f ));
97
98 const Exiv2::Value &getv3 = xmpData["Xmp.dc.three"].value();
99 UNUSED(getv3);
100 assert(isEqual(getv3.toFloat(), 5.0f/7.0f));
101 assert(getv3.ok());
102 assert(getv3.toLong() == 0); // long(5.0 / 7.0)
103 assert(getv3.ok());
104 assert(getv3.toRational() == Exiv2::Rational(5, 7));
105 assert(getv3.ok());
106
107 const Exiv2::Value &getv6 = xmpData["Xmp.dc.six"].value();
108 UNUSED(getv6);
109 assert(getv6.toLong() == 0);
110 assert(getv6.ok());
111 assert(getv6.toFloat() == 0.0f);
112 assert(getv6.ok());
113 assert(getv6.toRational() == Exiv2::Rational(0, 1));
114 assert(getv6.ok());
115
116 const Exiv2::Value &getv7 = xmpData["Xmp.dc.seven"].value();
117 getv7.toLong(); // this should fail
118 assert(!getv7.ok());
119
120 const Exiv2::Value &getv8 = xmpData["Xmp.dc.eight"].value();
121 UNUSED(getv8);
122 assert(getv8.toLong() == 1);
123 assert(getv8.ok());
124 assert(getv8.toFloat() == 1.0f);
125 assert(getv8.ok());
126 assert(getv8.toRational() == Exiv2::Rational(1, 1));
127 assert(getv8.ok());
128
129 // Deleting an XMP property
130 Exiv2::XmpData::iterator pos = xmpData.findKey(Exiv2::XmpKey("Xmp.dc.eight"));
131 if (pos == xmpData.end()) throw Exiv2::Error(Exiv2::kerErrorMessage, "Key not found");
132 xmpData.erase(pos);
133
134 // -------------------------------------------------------------------------
135 // Exiv2 has specialized values for simple XMP properties, arrays of simple
136 // properties and language alternatives.
137
138 // Add a simple XMP property in a known namespace
139 Exiv2::Value::AutoPtr v = Exiv2::Value::create(Exiv2::xmpText);
140 v->read("image/jpeg");
141 xmpData.add(Exiv2::XmpKey("Xmp.dc.format"), v.get());
142
143 // Add an ordered array of text values.
144 v = Exiv2::Value::create(Exiv2::xmpSeq); // or xmpBag or xmpAlt.
145 v->read("1) The first creator"); // The sequence in which the array
146 v->read("2) The second creator"); // elements are added is their
147 v->read("3) And another one"); // order in the array.
148 xmpData.add(Exiv2::XmpKey("Xmp.dc.creator"), v.get());
149
150 // Add a language alternative property
151 v = Exiv2::Value::create(Exiv2::langAlt);
152 v->read("lang=de-DE Hallo, Welt"); // The default doesn't need a
153 v->read("Hello, World"); // qualifier
154 xmpData.add(Exiv2::XmpKey("Xmp.dc.description"), v.get());
155
156 // According to the XMP specification, Xmp.tiff.ImageDescription is an
157 // alias for Xmp.dc.description. Exiv2 treats an alias just like any
158 // other property and leaves it to the application to implement specific
159 // behaviour if desired.
160 xmpData["Xmp.tiff.ImageDescription"] = "TIFF image description";
161 xmpData["Xmp.tiff.ImageDescription"] = "lang=de-DE TIFF Bildbeschreibung";
162
163 // -------------------------------------------------------------------------
164 // Register a namespace which Exiv2 doesn't know yet. This is only needed
165 // when properties are added manually. If the XMP metadata is read from an
166 // image, namespaces are decoded and registered at the same time.
167 Exiv2::XmpProperties::registerNs("myNamespace/", "ns");
168
169 // -------------------------------------------------------------------------
170 // Add a property in the new custom namespace.
171 xmpData["Xmp.ns.myProperty"] = "myValue";
172
173 // -------------------------------------------------------------------------
174 // There are no specialized values for structures, qualifiers and nested
175 // types. However, these can be added by using an XmpTextValue and a path as
176 // the key.
177
178 // Add a structure
179 Exiv2::XmpTextValue tv("16");
180 xmpData.add(Exiv2::XmpKey("Xmp.xmpDM.videoFrameSize/stDim:w"), &tv);
181 tv.read("9");
182 xmpData.add(Exiv2::XmpKey("Xmp.xmpDM.videoFrameSize/stDim:h"), &tv);
183 tv.read("inch");
184 xmpData.add(Exiv2::XmpKey("Xmp.xmpDM.videoFrameSize/stDim:unit"), &tv);
185
186 // Add an element with a qualifier (using the namespace registered above)
187 xmpData["Xmp.dc.publisher"] = "James Bond"; // creates an unordered array
188 xmpData["Xmp.dc.publisher[1]/?ns:role"] = "secret agent";
189
190 // Add a qualifer to an array element of Xmp.dc.creator (added above)
191 tv.read("programmer");
192 xmpData.add(Exiv2::XmpKey("Xmp.dc.creator[2]/?ns:role"), &tv);
193
194 // Add an array of structures
195 tv.read(""); // Clear the value
196 tv.setXmpArrayType(Exiv2::XmpValue::xaBag);
197 xmpData.add(Exiv2::XmpKey("Xmp.xmpBJ.JobRef"), &tv); // Set the array type.
198
199 tv.setXmpArrayType(Exiv2::XmpValue::xaNone);
200 tv.read("Birthday party");
201 xmpData.add(Exiv2::XmpKey("Xmp.xmpBJ.JobRef[1]/stJob:name"), &tv);
202 tv.read("Photographer");
203 xmpData.add(Exiv2::XmpKey("Xmp.xmpBJ.JobRef[1]/stJob:role"), &tv);
204
205 tv.read("Wedding ceremony");
206 xmpData.add(Exiv2::XmpKey("Xmp.xmpBJ.JobRef[2]/stJob:name"), &tv);
207 tv.read("Best man");
208 xmpData.add(Exiv2::XmpKey("Xmp.xmpBJ.JobRef[2]/stJob:role"), &tv);
209
210 // Add a creator contact info structure
211 xmpData["Xmp.iptc.CreatorContactInfo/Iptc4xmpCore:CiAdrCity"] = "Kuala Lumpur";
212 xmpData["Xmp.iptc.CreatorContactInfo/Iptc4xmpCore:CiAdrCtry"] = "Malaysia";
213 xmpData["Xmp.iptc.CreatorContactInfo/Iptc4xmpCore:CiUrlWork"] = "http://www.exiv2.org";
214
215 // -------------------------------------------------------------------------
216 // Output XMP properties
217 for (Exiv2::XmpData::const_iterator md = xmpData.begin();
218 md != xmpData.end(); ++md) {
219 std::cout << std::setfill(' ') << std::left
220 << std::setw(44)
221 << md->key() << " "
222 << std::setw(9) << std::setfill(' ') << std::left
223 << md->typeName() << " "
224 << std::dec << std::setw(3)
225 << std::setfill(' ') << std::right
226 << md->count() << " "
227 << std::dec << md->value()
228 << std::endl;
229 }
230
231 // -------------------------------------------------------------------------
232 // Serialize the XMP data and output the XMP packet
233 std::string xmpPacket;
234 if (0 != Exiv2::XmpParser::encode(xmpPacket, xmpData)) {
235 throw Exiv2::Error(Exiv2::kerErrorMessage, "Failed to serialize XMP data");
236 }
237 std::cout << xmpPacket << "\n";
238
239 // Cleanup
240 Exiv2::XmpParser::terminate();
241
242 return 0;
243 }
244 catch (Exiv2::AnyError& e) {
245 std::cout << "Caught Exiv2 exception '" << e << "'\n";
246 return -1;
247 }
248