Image Processing Toolbox™

analyze75read - Read image data from image file of Analyze 7.5 data set

Syntax

X = analyze75read(filename) X = analyze75read(info)

Description

X = analyze75read(filename) reads the image data from the image file of an Analyze 7.5 format data set specified by the string filename. The function returns the image data in X. For single-frame, grayscale images, X is an m-by-n array. analyze75read uses a data type for X that is consistent with the data type specified in the data set header file.

Analyze 7.5 is a 3-D biomedical image visualization and analysis product developed by the Biomedical Imaging Resource of the Mayo Clinic. An Analyze 7.5 data set is made of two files, a header file and an image file. The files have the same name with different file extensions. The header file has the file extension .hdr and the image file has the file extension .img. For more information about the Analyze 7.5 format, see the Mayo Clinic Web site.

X = analyze75read(info) reads the image data from the image file specified in the metadata structure info. info must be a valid metadata structure returned by the analyze75info function.

Note analyze75read returns image data in radiological orientation (LAS). This is the default used by the Analyze 7.5 format.

Examples

Example 1

Read image data from an Analyze 7.5 image file. The file used in the example can be downloaded from http://www.radiology.uiowa.edu/downloads/.

X = analyze75read('CT_HAND');

Because Analyze 7.5 format uses radiological orientation (LAS), flip the data for correct image display in MATLAB.

X = flipdim(X,1);

Select frames 51 to 56 and use reshape to create an array for montage.

Y = reshape(X(:,:,51:56),[size(X,1) size(X,2) 1 6]);
montage(Y);

Example 2

Call analyze75read with the metadata obtained from the header file using analyze75info.

info = analyze75info('CT_HAND.hdr');
X = analyze75read(info);

Class Support

X can be logical, uint8, int16, int32, single, or double. Complex and RGB data types are not supported.