DM3 Import for Gatan Digital Micrograph

Imports Gatan .DM3 format files with tags (images, spectra, & spectral images) into a MATLAB struct.

This script acts to import files from Gatan's .DM3 file format, utilized for electron microscopy, into a MATLAB structure. The fields of the MATLAB structure can then be referenced with the dot-operator.

For example, one can load and display a file with the appropriate scaled axes in nanometers and electrons with the following example script:

dm3struct = DM3Import( 'RandomBrightfieldImage.dm3' );
N = length( dm3struct.image_data );
imagesc( (1:N).*dmstruct.xaxis.scale (1:N).*dmstruct.yaxis.scale, ...
dm3struct.image_data.*dm3struct.intensity.scale );

This script currently imports images, EELS spectra, and spectral images. Now imports annotations (text) written on the image as well.

This script was constructed largely by parsing example DM3 files with a hex editor. It uses regular expressions to find the tags that indicate the start points of the various fields within the files, and then strips the data. To the best of my knowledge there is not existing documentation on the actual object used to write DM3 format files so it is not practical to output to DM3 format.