/usr/bin/dcmicmp

$dcmtk: dcmicmp v3.7.1 2026-10-15 $

dcmicmp: Compare DICOM images and compute difference metrics
usage: dcmicmp [options] dcmfile-in-1 dcmfile-in-2

parameters:
  dcmfile-in-1                  Reference DICOM image file for comparison
  dcmfile-in-2                  Test DICOM image file for comparison
                                ("-" for stdin)

general options:
  -h      --help                print this help text and exit
          --version             print version information and exit
          --arguments           print expanded command line arguments
  -q      --quiet               quiet mode, print no warnings and errors
  -v      --verbose             verbose mode, print processing details
  -d      --debug               debug mode, print debug information
  -ll     --log-level           [l]evel: string constant
                                (fatal, error, warn, info, debug, trace)
                                use level l for the logger
  -lc     --log-config          [f]ilename: string
                                use config file f for the logger
input options:
  input file format:
    +f    --read-file           read file format or data set (default)
    +fo   --read-file-only      read file format only
    -f    --read-dataset        read data set without file meta information
  input transfer syntax:
    -t=   --read-xfer-auto      use TS recognition (default)
    -td   --read-xfer-detect    ignore TS specified in the file meta header
    -te   --read-xfer-little    read with explicit VR little endian TS
    -tb   --read-xfer-big       read with explicit VR big endian TS
    -ti   --read-xfer-implicit  read with implicit VR little endian TS
image processing options:
  modality LUT transformation:
    +M    --use-modality        use modality LUT transformation (default)
    -M    --no-modality         ignore stored modality LUT transformation
  VOI LUT transformation:
    -W    --no-windowing        no VOI windowing (default)
    +Wi   --use-window          [n]umber: integer
                                use the n-th VOI window from image file
    +Wl   --use-voi-lut         [n]umber: integer
                                use the n-th VOI look up table from image file
    +Wm   --min-max-window      compute VOI window using min-max algorithm
                                on both images separately
    +Wn   --min-max-window-n    compute VOI window using min-max algorithm
                                on both images separately, ignoring extremes
    +Wr   --min-max-ref         compute VOI window using min-max algorithm
                                and use same window for the test image
    +Wq   --min-max-n-ref       compute VOI window using min-max algorithm,
                                ignoring extreme values
                                and use same window for the test image
    +Ww   --set-window          [c]enter [w]idth: float
                                compute VOI window using center c and width w
    +Wfl  --linear-function     set VOI LUT function to LINEAR
    +Wfs  --sigmoid-function    set VOI LUT function to SIGMOID
  presentation LUT transformation:
    +Pid  --identity-shape      set presentation LUT shape to IDENTITY
    +Piv  --inverse-shape       set presentation LUT shape to INVERSE
    +Pod  --lin-od-shape        set presentation LUT shape to LIN OD
image comparison metrics options:
  +ce     --check-error         [l]imit: integer
                                check if max absolute error <= limit
  +cm     --check-mae           [l]imit: float
                                check if mean absolute error <= limit
  +cr     --check-rmse          [l]imit: float
                                check if root mean square error <= limit
  +cp     --check-psnr          [l]imit: float
                                check if PSNR >= limit
  +cs     --check-snr           [l]imit: float
                                check if SNR >= limit
output options:
  +sd     --save-diff           [f]ilename: string
                                write secondary capture difference image
  +a      --amplify             [f]actor: float
                                multiply diff image pixel values by f