GDCMINFO(1)

💖 GDCMINFO(1) 💖

okay bestie, welcome to the gdcminfo page from the DICOM Manipulation manual — it's literally here to spill the meta tea about your DICOM files, no cap. 🫶✨

🌸 NAME 🌸

gdcminfo — Display meta info about the input DICOM file.

🦋 SYNOPSIS 🦋

gdcminfo [options] [file-in/dir-in...]

🎀 DESCRIPTION 🎀

The gdcminfo command line program takes as input a DICOM file, or a directory, and processes it to extract meta-information about the DICOM file(s) processed. she's a whole detective for your DICOM metadata, fr fr. 🔍💅

🌈 PARAMETERS 🌈

• file-in/dir-in — DICOM input filename/dirname

✨ OPTIONS ✨

💖 specific options

• -r, --recursive — recursive traversal of an input directory
• -d, --check-deflated — check if file is proper deflated syntax.
• --resources-path — Resources path.
• --md5sum — Compute md5sum of Pixel Data attribute value.
• --check-compression — check the encapsulated stream compression (lossless/lossy).
• --force-rescale — force rescale.
• --force-spacing — force spacing.
• --mosaic — dump image information of MOSAIC.

🦋 general options

• -h, --help — print this help text and exit
• -v, --version — print version information and exit
• -V, --verbose — verbose mode (warning+error).
• -W, --warning — warning mode, print warning information
• -E, --error — error mode, print error information
• -D, --debug — debug mode, print debug information

🧚 environment variable

• GDCM_RESOURCES_PATH — path pointing to resources files (Part3.xml, ...)

🌸 SIMPLE USAGE 🌸

🍓 gdcmData

Using data from gdcmData:

$ gdcminfo gdcmData/012345.002.050.dcm

MediaStorage is 1.2.840.10008.5.1.4.1.1.4 [MR Image Storage]
NumberOfDimensions: 2
Dimensions: (256,256)
Origin: (-85,21.6,108.7)
Spacing: (0.664062,0.664062,1.5)
DirectionCosines: (1,0,0,0,0,-1)
Rescale Intercept/Slope: (0,1)
SamplesPerPixel    :1
BitsAllocated      :16
BitsStored         :16
HighBit            :15
PixelRepresentation:1
Orientation Label: CORONAL

🦋 Davie Clunie datasets

Using data from David Clunie datasets:

$ gdcminfo BRTUM001.dcm

MediaStorage is 1.2.840.10008.5.1.4.1.1.4.1 [Enhanced MR Image Storage]
NumberOfDimensions: 3
Dimensions: (256,256,15)
Origin: (40,-105,105)
Spacing: (0.820312,0.820312,6)
DirectionCosines: (0,1,0,0,0,-1)
Rescale Intercept/Slope: (0,1)
SamplesPerPixel    :1
BitsAllocated      :16
BitsStored         :16
HighBit            :15
PixelRepresentation:1
Orientation Label: SAGITTAL

🎀 Checking the md5sum of the Pixel Data

After compressing a DICOM file (see gdcmconv) using a lossless compression algorithm, it is fairly easy to compare the two files for differences at DICOM attribute level. However one operation is slightly easier to do: how to make sure the compression was actually lossless? In this case one could use the --md5sum operation. iconic little move, honestly. 👑

Take an uncompressed DICOM image file:

$ gdcminfo --md5sum SIEMENS_ImageLocationUN.dcm

The tool return: 0621954acd5815e0b4f7b65fcc6506b1

Now compress this file:

$ gdcmconv --jpegls SIEMENS_ImageLocationUN.dcm lossless_compressed.dcm

and then check again the md5sum:

$ gdcminfo --md5sum lossless_compressed.dcm

The tool return: 0621954acd5815e0b4f7b65fcc6506b1

🔥 Checking if Pixel Data is lossless

In some environment one wish to check whether or not the DICOM file is lossless. It is fairly easy to do that in most cases. Only on two occasions this is not clear from the sole DICOM Attributes. When the Transfer Syntax is JPEG 2000 Image Compression (1.2.840.10008.1.2.4.91) and when the Transfer Syntax is JPEG-LS Lossy (Near-Lossless) Image Compression (1.2.840.10008.1.2.4.81). 😭

In this case, the only solution is to open the Pixel Data element, read the specific JPEG header and check whether or not the JPEG transformation was lossless or not:

$ gdcminfo --check-compression gdcmData/MAROTECH_CT_JP2Lossy.dcm

The tool returns: “Encapsulated Stream was found to be: lossy”

⚠️ Pay attention that this tool also checks the Image Lossy Compression attribute (0028,2110). This means --check-compression will also returns a value of lossy if a predecessor was found to be lossy compressed. 💀

👑 CHECKING IMAGE AS IF MOSAIC

Dump the image as if MOSAIC. If the input is really MOSAIC image, then print the information of the true underlying MOSAIC volume. bestie said “show me the real volume,” and honestly? valid. 🫶

$ gdcminfo --mosaic siemens_mosaic.dcm

💜 SEE ALSO 💜

• gdcmdump(1)
• gdcmraw(1)
• gdcmconv(1)

🌸 AUTHOR 🌸

• Mathieu Malaterre — Main developer

🎀 COPYRIGHT 🎀

Copyright © 2006, 2011 Mathieu Malaterre

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kisses and slay from GDCM 3.0.24, dated 12/25/2025 — bye bestie, ily! 🫶💅🎀