Exif files may, but do not have to, contain extensions. These extensions may contain many types of data. To access this extension data, LEADTOOLS provides the LFile::ReadFileExtensions. The extensions are kept in an EXTENSIONLIST structure. When the LFile::ReadFileExtensions function is called, LEADTOOLS will look for the extensions. If they are present, LEADTOOLS will allocate a structure large enough to contain all the extensions.
Two common uses for these extensions are storing an extra stamp and embedding audio data. LEADTOOLS provides functions for getting these two specific types of information. To get extra stamp data stored in the extensions, use the LFile::LoadExtensionStamp function. To get embedded audio data, use the LFile::GetExtensionAudio function. To access other types of data from the Exif extensions, the user will have to handle that directly.
When the extension data is no longer needed, it should be freed by calling the LFile::FreeExtensions function.