Available in LEADTOOLS Imaging Pro, Vector, Document, and Medical Imaging toolkits. |
LFile::EnumTagsCallBack
#include "ltwrappr.h"
virtual L_INT LFile::EnumTagsCallBack(uTag, uType, uCount)
L_UINT16 uTag; |
/* tag to identify the data in the TIFF file */ |
L_UINT16 uType; |
/* tag data type */ |
L_UINT32 uCount; |
/* number of values */ |
The LFile::EnumTags function will call this callback for each tag present on the page.
Parameter |
Description |
|
uTag |
Tag to identify the data in the TIFF file. This may be any tag specified in LFileSettings::SetTag, or any other tag added by the TIFF filter when saving the file. For example, all of the TIFF comments would generate a particular TIFF tag. |
|
uType |
Tagged data type. Valid values are: |
|
Value |
Meaning |
|
TAG_BYTE |
[1] Byte. |
|
TAG_ASCII |
[2] Byte in the range of 0 to 255. |
|
TAG_SBYTE |
[6] Byte used as signed number in the range of -128 to +127. |
|
TAG_UNDEFINED |
[7] Byte, with application-defined usage. |
|
TAG_SHORT |
[3] Two bytes, unsigned. |
|
TAG_SSHORT |
[8] Two bytes, signed. |
|
TAG_LONG |
[4] Four bytes, unsigned. |
|
TAG_SLONG |
[9] Four bytes, signed. |
|
TAG_RATIONAL |
[5] Eight bytes, used as a pair of unsigned long integers, where the first number is the numerator and the second is the denominator of a fraction. |
|
TAG_SRATIONAL |
[10] Eight bytes, used as a pair of signed long integers, where the first number is the numerator and the second is the denominator of a fraction. |
|
TAG_FLOAT |
[11] Four bytes used as a floating point number. |
|
TAG_DOUBLE |
[12] Eight bytes used as a double-precision floating point number. |
|
uCount |
Number of elements of type uType. Note that this is not the same as the number of bytes. For example, if uCount is 10 and uType is TAG_LONG, you will need 10 x 4 = 40 bytes to read the tag data. |
Returns
SUCCESS |
The function was successful. |
< 1 |
An error occurred. Refer to Return Codes. |
Comments
The LFile::EnumTags function calls this callback for each tag in the page. For more information, refer to LFile::EnumTags.
Do not attempt to use the LFile::DeleteTag function to delete tags from inside an LFile::EnumTagsCallback callback function. If you want to delete tags that you enumerate, use LFile::EnumTagsCallback to add the tags to a list. Upon returning from LFile::EnumTags, you can delete all the tags from the list.
See Also
Example
For an example, refer to LFile::EnumTags.