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Read image data from image file of Analyze 7.5 data set



X = analyze75read(filename) reads the image data from the image file of an Analyze 7.5 format data set specified by the character vector filename. The function returns the image data in X.

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.


By default, analyze75read returns image data in radiological orientation (LAS). For more information, see Read Image Data from Analyze 7.5 File.


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.


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Read image data from an Analyze 7.5 file.

X = analyze75read('brainMRI');

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

X = flip(X);

Then, reshape the data to create an array that can be displayed using montage. Select frames 12 to 17.

Y = reshape(X(:,:,12:17),[size(X,1) size(X,2) 1 6]);

Figure contains an axes object. The axes object contains an object of type image.

Read image data from an Analyze 7.5 data set, using the structure returned by analyze75info to specify the data set. First, use analyze75info to create the info structure.

info = analyze75info('brainMRI');

Call analyze75read to read image data from the data set, specifying the info structure returned by analyze75info.

X = analyze75read(info);

Input Arguments

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Name of Analyze 7.5 data set, specified as a character vector. You don’t need to specify a file extension.

Example: info = analyze75info('brainMRI');

Data Types: char

Information about the Analyze 7.5 data set, specified as a structure returned by the analyze75info function.

Data Types: struct

Output Arguments

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Image data from Analyze 7.5 data set, returned as an array. X can be logical, uint8, int16, int32, single, or double. analyze75read uses a data type for X that is consistent with the data type specified in the data set header file. Complex and RGB data types are not supported. For single-frame, grayscale images, X is an m-by-n array.

Version History

Introduced before R2006a