Exiv2
metadatum.hpp
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20 #ifndef METADATUM_HPP_
21 #define METADATUM_HPP_
22 
23 // *****************************************************************************
24 #include "exiv2lib_export.h"
25 
26 // included header files
27 #include "value.hpp"
28 
29 // *****************************************************************************
30 // namespace extensions
31 namespace Exiv2 {
32 
33 // *****************************************************************************
34 // class declarations
35  class ExifData;
36 
37 // *****************************************************************************
38 // class definitions
39 
44  class EXIV2API Key {
45  public:
47  typedef std::auto_ptr<Key> AutoPtr;
48 
50 
51  virtual ~Key();
54 
56 
57 
63  virtual std::string key() const =0;
65  virtual const char* familyName() const =0;
67  virtual std::string groupName() const =0;
69  virtual std::string tagName() const =0;
71  virtual std::string tagLabel() const =0;
73  virtual uint16_t tag() const =0;
79  AutoPtr clone() const;
86  std::ostream& write(std::ostream& os) const { return os << key(); }
88 
89  protected:
91 
92 
96  Key& operator=(const Key& rhs);
98 
99  private:
101  virtual Key* clone_() const =0;
102 
103  }; // class Key
104 
106  inline std::ostream& operator<<(std::ostream& os, const Key& key)
107  {
108  return key.write(os);
109  }
110 
115  class EXIV2API Metadatum {
116  public:
118 
119  Metadatum();
122  Metadatum(const Metadatum& rhs);
124  virtual ~Metadatum();
126 
128 
129 
133  virtual void setValue(const Value* pValue) =0;
140  virtual int setValue(const std::string& buf) =0;
142 
144 
145 
150  std::string print(const ExifData* pMetadata =0) const;
162  virtual long copy(byte* buf, ByteOrder byteOrder) const =0;
184  virtual std::ostream& write(
185  std::ostream& os,
186  const ExifData* pMetadata =0
187  ) const =0;
194  virtual std::string key() const =0;
196  virtual const char* familyName() const =0;
198  virtual std::string groupName() const =0;
200  virtual std::string tagName() const =0;
202  virtual std::string tagLabel() const =0;
204  virtual uint16_t tag() const =0;
206  virtual TypeId typeId() const =0;
208  virtual const char* typeName() const =0;
210  virtual long typeSize() const =0;
212  virtual long count() const =0;
214  virtual long size() const =0;
216  virtual std::string toString() const =0;
222  virtual std::string toString(long n) const =0;
228  virtual long toLong(long n =0) const =0;
234  virtual float toFloat(long n =0) const =0;
240  virtual Rational toRational(long n =0) const =0;
254  virtual Value::AutoPtr getValue() const =0;
268  virtual const Value& value() const =0;
270 
271  protected:
273 
274 
278  Metadatum& operator=(const Metadatum& rhs);
280 
281  }; // class Metadatum
282 
287  inline std::ostream& operator<<(std::ostream& os, const Metadatum& md)
288  {
289  return md.write(os);
290  }
291 
296  EXIV2API bool cmpMetadataByTag(const Metadatum& lhs, const Metadatum& rhs);
301  EXIV2API bool cmpMetadataByKey(const Metadatum& lhs, const Metadatum& rhs);
302 
303 } // namespace Exiv2
304 
305 #endif // #ifndef METADATUM_HPP_
A container for Exif data. This is a top-level class of the Exiv2 library. The container holds Exifda...
Definition: exif.hpp:434
Abstract base class defining the Key of a metadatum. Keys are used to identify and group metadata.
Definition: metadatum.hpp:44
virtual std::string groupName() const =0
Return the name of the group (the second part of the key)
virtual std::string key() const =0
Return the key of the metadatum as a string. The key is of the form 'familyName.groupName....
std::ostream & write(std::ostream &os) const
Write the key to an output stream. You do not usually have to use this function; it is used for the i...
Definition: metadatum.hpp:86
virtual std::string tagLabel() const =0
Return a label for the tag.
virtual uint16_t tag() const =0
Return the tag number.
std::auto_ptr< Key > AutoPtr
Shortcut for a Key auto pointer.
Definition: metadatum.hpp:47
virtual const char * familyName() const =0
Return an identifier for the type of metadata (the first part of the key)
virtual std::string tagName() const =0
Return the name of the tag (which is also the third part of the key)
Abstract base class defining the interface to access information related to one metadata tag.
Definition: metadatum.hpp:115
virtual long size() const =0
Return the size of the value in bytes.
virtual TypeId typeId() const =0
Return the type id of the value.
virtual long typeSize() const =0
Return the size in bytes of one component of this type.
virtual Value::AutoPtr getValue() const =0
Return an auto-pointer to a copy (clone) of the value. The caller owns this copy and the auto-poiner ...
virtual int setValue(const std::string &buf)=0
Set the value to the string buf. Uses Value::read(const std::string& buf). If the metadatum does not ...
virtual long copy(byte *buf, ByteOrder byteOrder) const =0
Write value to a data buffer and return the number of bytes written.
virtual std::string toString(long n) const =0
Return the n-th component of the value converted to a string. The behaviour of the method is undefine...
virtual uint16_t tag() const =0
Return the tag.
virtual std::string tagLabel() const =0
Return a label for the tag.
virtual std::ostream & write(std::ostream &os, const ExifData *pMetadata=0) const =0
Write the interpreted value to an output stream, return the stream.
virtual long toLong(long n=0) const =0
Return the n-th component of the value converted to long. The return value is -1 if the value is not ...
virtual const Value & value() const =0
Return a constant reference to the value.
virtual long count() const =0
Return the number of components in the value.
virtual std::string tagName() const =0
Return the name of the tag (which is also the third part of the key)
virtual const char * familyName() const =0
Return the name of the metadata family (which is also the first part of the key)
virtual std::string toString() const =0
Return the value as a string.
virtual std::string groupName() const =0
Return the name of the metadata group (which is also the second part of the key)
virtual float toFloat(long n=0) const =0
Return the n-th component of the value converted to float. The return value is -1 if the value is not...
virtual const char * typeName() const =0
Return the name of the type.
virtual Rational toRational(long n=0) const =0
Return the n-th component of the value converted to Rational. The return value is -1/1 if the value i...
virtual void setValue(const Value *pValue)=0
Set the value. This method copies (clones) the value pointed to by pValue.
virtual std::string key() const =0
Return the key of the metadatum. The key is of the form 'familyName.groupName.tagName'....
Common interface for all types of values used with metadata.
Definition: value.hpp:51
std::auto_ptr< Value > AutoPtr
Shortcut for a Value auto pointer.
Definition: value.hpp:54
Provides classes and functions to encode and decode Exif and Iptc data. The libexiv2 API consists of ...
Definition: asfvideo.hpp:36
EXIV2API std::ostream & operator<<(std::ostream &os, const DataSet &dataSet)
Output operator for dataSet.
Definition: datasets.cpp:709
EXIV2API bool cmpMetadataByTag(const Metadatum &lhs, const Metadatum &rhs)
Compare two metadata by tag. Return true if the tag of metadatum lhs is less than that of rhs.
Definition: metadatum.cpp:71
TypeId
Exiv2 value type identifiers.
Definition: types.hpp:119
ByteOrder
Type to express the byte order (little or big endian)
Definition: types.hpp:102
std::pair< int32_t, int32_t > Rational
8 byte signed rational type.
Definition: types.hpp:99
EXIV2API bool cmpMetadataByKey(const Metadatum &lhs, const Metadatum &rhs)
Compare two metadata by key. Return true if the key of metadatum lhs is less than that of rhs.
Definition: metadatum.cpp:77