setSubDirectory

Make subIFD the current IFD

Syntax

setSubDirectory(t,offset)

Description

setSubDirectory(t,offset) sets the current IFD to the subimage file directory (subIFD) specified by offset. Use this function when you want to access subIFDs linked through the SubIFD tag.

Examples

Set Subimage File Directory

Open a TIFF file and read the value of the SubIFD tag in the current IFD. The SubIFD tag contains byte offsets that specify the location of subIFDs in the IFD.

t = Tiff('example.tif','r');

Read the value of the SubIFD tag to get the subdirectory offsets. Multiple values in the offsets array indicate multiple subdirectories.

offsets = getTag(t,'SubIFD')

offsets = uint64

90114

Navigate to the first subIFD. If you have multiple subdirectories, then you can set any one of the subdirectories as the current directory.

setSubDirectory(t,offsets(1))
close(t);

Input Arguments

t — Tiff object

Tiff object

Tiff object representing a TIFF file. Use the Tiff function to create the object.

offset — Offset from current directory

positive integer

Offset from the current directory, specified as a positive integer. Specify offset value in bytes from the start of the file.

Get value of offset from the SubIFD tag.

Data Types: double

Algorithms

References

This function corresponds to the TIFFSetSubDirectory function in the LibTIFF C API. To use this function, you must be familiar with the TIFF specification and technical notes. View this documentation at LibTIFF - TIFF Library and Utilities.

Version History

Introduced in R2009b