XMP Toolkit SDK  6.0.0
XMP.hpp File Reference

Overall header file for the XMP Toolkit. More...

#include "XMP_Environment.h"
#include "XMP_Version.h"
#include "XMP_Const.h"
#include "TXMPMeta.hpp"
#include "TXMPIterator.hpp"
#include "TXMPUtils.hpp"

Go to the source code of this file.

Detailed Description

Overall header file for the XMP Toolkit.

This is an overall header file, the only one that C++ clients should include.

The full client API is in the TXMPMeta.hpp, TXMPIterator.hpp, TXMPUtils.hpp headers. Read these for information, but do not include them directly. The TXMP... classes are C++ template classes that must be instantiated with a string class such as std::string. The string class is used to return text strings for property values, serialized XMP, and so on. Clients must also compile XMP.incl_cpp to ensure that all client-side glue code is generated. This should be done by including it in exactly one client source file.

There are two C preprocessor macros that simplify use of the templates:

  • TXMP_STRING_TYPE - Define this as the string class to use with the template. You will get the template headers included and typedefs (SXMPMeta, and so on) to use in your code.
  • TXMP_EXPAND_INLINE - Define this as 1 if you want to have the template functions expanded inline in your code. Leave it undefined, or defined as 0, to use out-of-line instantiations of the template functions. Compiling XMP.incl_cpp generates explicit out-of-line instantiations if TXMP_EXPAND_INLINE is off.

The template parameter, class tStringObj, must have the following member functions (which match those for std::string):

 tStringObj& assign ( const char * str, size_t len )
 size_t size() const
 const char * c_str() const

The string class must be suitable for at least UTF-8. This is the encoding used for all general values, and is the default encoding for serialized XMP. The string type must also be suitable for UTF-16 or UTF-32 if those serialization encodings are used. This mainly means tolerating embedded 0 bytes, which std::string does.

Definition in file XMP.hpp.