In This Topic ▼

LFile::EnumGeoKeysCallBack

#include "ltwrappr.h"

virtual L_INT LFile::EnumGeoKeysCallBack(uTag, uType, uCount, pData)

L_UINT16 uTag;

GeoKey ID

L_UINT16 uType;

GeoKey type

L_UINT uCount;

number of GeoKey values

L_VOID * pData;

pointer to GeoKey data

This function is called for each GeoKey enumerated by the LFile::EnumGeoKeys function.

Parameter Description
uTag GeoKey ID identifying the GeoTIFF key.
uType The type of GeoKey. This indicates whether the data pointed to by pData is SHORT, DOUBLE or ASCII. Possible values are:
Value Meaning
TAG_ASCII [2] Byte in the range of 0 to 255. Null-terminated.
TAG_SHORT [3] Two bytes, unsigned.
TAG_DOUBLE [12] Eight bytes used as a double-precision floating-point number.
TAG_IFD [13] 32-bit IFD offset.
TAG_LONG8 [16] Unsigned 64-bit integer (valid only for BigTIFF formats).
TAG_SLONG8 [17] Signed 64-bit integer (valid only for BigTIFF formats).
TAG_IFD8 [18] 64-bit IFD offset (valid only for BigTIFF formats).
uCount The number of items in the pData buffer. Note that this does not describe the number of bytes. For example, if uCount is 10 and uType is TAG_DOUBLE, you will need 10 x 8 = 80 bytes to read the tag data.
pData A void pointer that you can use to access a variable or structure containing the GeoKey data. This gives you a way to receive data indirectly from the function that uses this callback function.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

This function will be called for every GeoKey on the page.

Platforms

Win32, x64.

Help Version 20.0.2020.2.17
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2020 LEAD Technologies, Inc. All Rights Reserved.

LEADTOOLS Raster Imaging C++ Class Library Help