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DICOM File compression

My line of work requires the use of DICOM files. Each DICOM file constitutes many .dcm files in a single directory. I am required to send these files over the network, a process which is somewhat so due to the massive size of the files. I am also a programmer and I was wondering what is the ideal way to compress such files? I'm talking about a compression that will be made on the local computer and later decompressed on the destination computer (namely the compression is solely for speeding up the over-the-network transfer of the file). Is there a simple way to crop the DICOM files? (the files contain imaging of an entire head, whereas I'm only interested in a small part of the head).

Thanks!

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mason Avatar asked Jul 07 '10 14:07

mason


People also ask

What is DICOM compression?

DICOM support lossless compression schemes like run-length encoding, Huffman coding, LZW coding, area coding, and arithmetic coding. The RLE is used for medical image compression in hybrid approach, where gray scale value gives certain interesting fact about the distribution in image.

What is the difference between JPEG and DICOM?

JPEG files contain a single monochrome (or color) image. They also have no associated meta-data. DICOM files on the other hand, can contain multiple monochrome images along with a rich set of metadata. Such information can be anything from patient information, institution, modality, and more.


1 Answers

In medical context, lossy compression is somewhere between not encouraged and forbidden. If you'd insist on cropping existing datasets the standard demands you to form at least new image & series UIDs. The standard does allow losless compression in the form of jpeg2000, but it is quite rare - if I had to bet I'd say your dataset is uncompressed altogether.

In my experience it is significantly better to compress a medical dataset as a solid archive - that is, unify all the images into a single stream. This makes a lot of sense, as there is typically a lot of similarity between nearby images and this is the way to take advantage of that similarity (a unified compression dictionary). This is available as a command line option both to rar and gzip compressors.

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Ofek Shilon Avatar answered Oct 18 '22 23:10

Ofek Shilon