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LFile::WriteMetaData

#include "ltwrappr.h"

virtual L_INT LFile::WriteMetaData(uFlags, pSaveFileOption)

L_UINT uFlags;	/* type of metadata */
pSAVEFILEOPTION pSaveFileOption;	/* reserved for future use */

Writes metadata of the specified type to the file specified for this file object.

Parameter	Description
uFlags	Flags that indicate the type of metadata to write. Possible values are:
	Value	Meaning
	METADATA_COMMENTS	[0x0001] Write comments.
	METADATA_TAGS	[0x0002] Write tags.
	METADATA_MARKERS	[0x0004] Write markers.
	METADATA_GEOKEYS	[0x0008] Write GeoKeys.
	METADATA_ALL	[0xFFFF] Write all metadata (tags, comments and markers).
	These values can be combined using OR (|) or +.
pSaveFileOption	Reserved for future use. Pass NULL.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

LFile::WriteMetaData can be used to update an existing file with comments, tags and/or markers.

Before calling this function, the user should set:

• Comments using the LFileSettings::SetComment function.

• Tags using the LFileSettings::SetTag function.

• Markers using the LMarker::SetAsGlobalMarkers function.

When you add or remove comments or tags, the comments and tags array at the end of the TIFF/Exif image file is re-written. When you modify existing comments or tags, the new value is added to the file and the IFD is modified as necessary. In all of these cases, there is no image recompression.

Some restrictions apply to this function if you use an IFD to indicate to which page to write the metadata. See the Loading and Saving Large TIFF Files topic for more information.

Required DLLs and Libraries

LTFIL For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

See Also

Functions:	LMarker::Copy, LMarker::Create, LMarker::Delete, LMarker::DeleteIndex, LMarker::Enum, LMarker::EnumMarkersCallBack, LMarker::Free, LMarker::GetCount, LMarker::GetHandle, LMarker::GetGlobalMarkers, LMarker::Insert, LMarker::Load, LMarker::SetAsGlobalMarkers, LMarker::SetHandle, LFile::WriteMetaData, LFile::WriteComment, LFile::WriteTag, Class Members
Topics:	Raster Image Functions: Markers
	Working with Markers

Example

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName
L_INT LFile__WriteMetaDataExample()
{
   L_INT nRet;
   L_INT nVal = 1234;
   LFile MyFile;
   LFileSettings MyFileSettings;
   MyFileSettings.SetTag(0x8001, TAG_LONG, 1, &nVal);
   nRet = MyFileSettings.SetComment(CMNT_SZDESC, (unsigned char *) TEXT("Comment written with WriteMetaData"), 37);
   if(nRet < 0)
      return nRet;
   MyFile.SetFileName(MAKE_IMAGE_PATH(TEXT("clean.tif")));
   nRet = MyFile.WriteMetaData(METADATA_ALL, NULL);
   if(nRet != SUCCESS)
      return nRet;
   return SUCCESS;
}