Notes on Exif Data Types - Raster Imaging C API Help

Notes on Exif Data Types

The Exif standard defines the following data types for comments. Usage is dependent of your development platform. To see the usage, refer to the code example for your platform.

Data type Description

UNDEFINED

The data type is determined by the field.

SHORT

Integer

LONG

Long integer

ASCII

Character string

BYTE

Array of bytes

RATIONAL

An array of two unsigned long integers that express a fraction. The first value is the numerator, and the second is the denominator.

SRATIONAL

An array of two signed long integers that express a fraction. The first value is the numerator, and the second is the denominator.

The byte length of a comment is based on the data type. For example, an SRATIONAL with a length of 3 is an array of 6 long integers.

When a comment that requires an array is set, the array can be zero-based (where the first element has an index of 0) or one-based (where the first element has an index of 1). When you get a comment that is an array, it will always be zero-based.

See Also

For more information about Exif file comments, refer to:

Exif File Comments

For more information and sample code, refer to:

L_DeleteComment

L_SetComment

L_GetComment

L_ReadFileComment

Help Version 20.0.2018.7.30
Products | Support | Contact Us | Copyright Notices
© 1991-2018 LEAD Technologies, Inc. All Rights Reserved.

LEADTOOLS Raster Imaging C API Help