dcmdump(1)

NAME
dcmdump - Dump DICOM file and data set

SYNOPSIS

dcmdump [options] dcmfile-in...

DESCRIPTION

The dcmdump utility dumps the contents of a DICOM file (file format or raw data set) to stdout in textual form. Attributes with very large value fields (e.g. pixel data) can be described as '(not loaded)'. String value fields will be delimited with square brackets ([]). Known UIDs will be displayed by their names prefixed by an equals sign (e.g. '=MRImageStorage') unless this mapping would be explicitly switched off. Empty value fields are described as '(no value available)'.

If dcmdump reads a raw data set (DICOM data without a file format meta-header) it will attempt to guess the transfer syntax by examining the first few bytes of the file. It is not always possible to correctly guess the transfer syntax and it is better to convert a data set to a file format whenever possible (using the dcmconv utility). It is also possible to use the -f and -t[ieb] options to force dcmdump to read a dataset with a particular transfer syntax.

PARAMETERS

dcmfile-in  DICOM input file or directory to be dumped ("-" for stdin)

OPTIONS

  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
input files:
  +sd  --scan-directories
         scan directories for input files (dcmfile-in)
  +sp  --scan-pattern  [p]attern: string (only with --scan-directories)
         pattern for filename matching (wildcards)
         # possibly not available on all systems
  -r   --no-recurse
         do not recurse within directories (default)
  +r   --recurse
         recurse within specified directories
long tag values:
  +M   --load-all
         load very long tag values (default)
  -M   --load-short
         do not load very long values (e.g. pixel data)
  +R   --max-read-length  [k]bytes: integer (4..4194302, default: 4)
         set threshold for long values to k kbytes
parsing of file meta information:
  +ml  --use-meta-length
         use file meta information group length (default)
  -ml  --ignore-meta-length
         ignore file meta information group length
parsing of odd-length attributes:
  +ao  --accept-odd-length
         accept odd length attributes (default)
  +ae  --assume-even-length
         assume real length is one byte larger
handling of explicit VR:
  +ev  --use-explicit-vr
         use explicit VR from dataset (default)
  -ev  --ignore-explicit-vr
         ignore explicit VR (prefer data dictionary)
handling of non-standard VR:
  +vr  --treat-as-unknown
         treat non-standard VR as unknown (default)
  -vr  --assume-implicit
         try to read with implicit VR little endian TS
handling of undefined length UN elements:
  +ui  --enable-cp246
         read undefined len UN as implicit VR (default)
  -ui  --disable-cp246
         read undefined len UN as explicit VR
handling of defined length UN elements:
  -uc  --retain-un
         retain elements as UN (default)
  +uc  --convert-un
         convert to real VR if known
handling of private max-length elements (implicit VR):
  -sq  --maxlength-dict
         read as defined in dictionary (default)
  +sq  --maxlength-seq
         read as sequence with undefined length
handling of wrong delimitation items:
  -rd  --use-delim-items
         use delimitation items from dataset (default)
  +rd  --replace-wrong-delim
         replace wrong sequence/item delimitation items
handling of illegal undefined length OB/OW elements:
  -oi  --illegal-obow-rej
         reject dataset with illegal element (default)
  +oi  --illegal-obow-conv
         convert undefined length OB/OW element to SQ
handling of VOI LUT Sequence with OW VR and explicit length:
  -vi  --illegal-voi-rej
         reject dataset with illegal VOI LUT (default)
  +vi  --illegal-voi-conv
         convert illegal VOI LUT to SQ
handling of explicit length pixel data for encaps. transfer syntaxes:
  -pe  --abort-expl-pixdata
         abort on explicit length pixel data (default)
  +pe  --use-expl-pixdata
         use explicit length pixel data
general handling of parser errors:
  +Ep  --ignore-parse-errors
         try to recover from parse errors
  -Ep  --handle-parse-errors
         handle parse errors and stop parsing (default)
other parsing options:
  +st  --stop-after-elem  [t]ag: "gggg,eeee" or dictionary name
         stop parsing after element specified by t
  +sb  --stop-before-elem [t]ag: "gggg,eeee" or dictionary name
         stop parsing before element specified by t
         # only considers elements on main dataset level and also
         # works if the given tag is not present in the file
automatic data correction:
  +dc  --enable-correction
         enable automatic data correction (default)
  -dc  --disable-correction
         disable automatic data correction
bitstream format of deflated input:
  +bd  --bitstream-deflated
         expect deflated bitstream (default)
  +bz  --bitstream-zlib
         expect deflated zlib bitstream

  processing options

specific character set:
  +U8  --convert-to-utf8
         convert all element values that are affected
         by Specific Character Set (0008,0005) to UTF-8
         # requires support from an underlying character encoding library
         # (see output of --version on which one is available)

  output options

printing:
  +L   --print-all
         print long tag values completely
  -L   --print-short
         print long tag values shortened (default)
  +T   --print-tree
         print hierarchical structure as a simple tree
  -T   --print-indented
         print hierarchical structure indented (default)
  +F   --print-filename
         print header with filename for each input file
  +Fs  --print-file-search
         print header with filename only for those input files
         that contain one of the searched tags
mapping:
  +Un  --map-uid-names
         map well-known UID numbers to names (default)
  -Un  --no-uid-names
         do not map well-known UID numbers to names
quoting:
  +Qn  --quote-nonascii
         quote non-ASCII and control chars as XML markup
  +Qo  --quote-as-octal
         quote non-ASCII and control chars as octal numbers
  -Qn  --print-nonascii
         print non-ASCII and control chars (default)
color:
  +C   --print-color
         use ANSI escape codes for colored output
  -C   --no-color
         do not use any ANSI escape codes (default)
error handling:
  -E   --stop-on-error
         do not print if file is damaged (default)
  +E   --ignore-errors
         attempt to print even if file is damaged
searching:
  +P   --search  [t]ag: "gggg,eeee" or dictionary name
         print the textual dump of tag t
         this option can be specified multiple times
         (default: the complete file is printed)
  +s   --search-all
         print all instances of searched tags (default)
  -s   --search-first
         only print first instance of searched tags
  +p   --prepend
         prepend sequence hierarchy to printed tag,
         denoted by: (gggg,eeee).(gggg,eeee).*
         (only when used with --search)
  -p   --no-prepend
         do not prepend hierarchy to tag (default)
writing:
  +W   --write-pixel  [d]irectory: string
         write pixel data to a .raw file stored in d
         (little endian, filename created automatically)

NOTES

Adding directories as a parameter to the command line only makes sense if option --scan-directories is also given. If the files in the provided directories should be selected according to a specific name pattern (e.g. using wildcard matching), option --scan-pattern has to be used. Please note that this file pattern only applies to the files within the scanned directories, and, if any other patterns are specified on the command line outside the --scan-pattern option (e.g. in order to select further files), these do not apply to the specified directories.

LOGGING

The level of logging output of the various command line tools and underlying libraries can be specified by the user. By default, only errors and warnings are written to the standard error stream. Using option --verbose also informational messages like processing details are reported. Option --debug can be used to get more details on the internal activity, e.g. for debugging purposes. Other logging levels can be selected using option --log-level. In --quiet mode only fatal errors are reported. In such very severe error events, the application will usually terminate. For more details on the different logging levels, see documentation of module 'oflog'.

In case the logging output should be written to file (optionally with logfile rotation), to syslog (Unix) or the event log (Windows) option --log-config can be used. This configuration file also allows for directing only certain messages to a particular output stream and for filtering certain messages based on the module or application where they are generated. An example configuration file is provided in <etcdir>/logger.cfg.

COMMAND LINE

All command line tools use the following notation for parameters: square brackets enclose optional values (0-1), three trailing dots indicate that multiple values are allowed (1-n), a combination of both means 0 to n values.

Command line options are distinguished from parameters by a leading '+' or '-' sign, respectively. Usually, order and position of command line options are arbitrary (i.e. they can appear anywhere). However, if options are mutually exclusive the rightmost appearance is used. This behavior conforms to the standard evaluation rules of common Unix shells.

In addition, one or more command files can be specified using an '@' sign as a prefix to the filename (e.g. @command.txt). Such a command argument is replaced by the content of the corresponding text file (multiple whitespaces are treated as a single separator unless they appear between two quotation marks) prior to any further evaluation. Please note that a command file cannot contain another command file. This simple but effective approach allows one to summarize common combinations of options/parameters and avoids longish and confusing command lines (an example is provided in file <datadir>/dumppat.txt).

ENVIRONMENT

The dcmdump utility will attempt to load DICOM data dictionaries specified in the DCMDICTPATH environment variable. By default, i.e. if the DCMDICTPATH environment variable is not set, the file <datadir>/dicom.dic will be loaded unless the dictionary is built into the application (default for Windows).

The default behavior should be preferred and the DCMDICTPATH environment variable only used when alternative data dictionaries are required. The DCMDICTPATH environment variable has the same format as the Unix shell PATH variable in that a colon (':') separates entries. On Windows systems, a semicolon (';') is used as a separator. The data dictionary code will attempt to load each file specified in the DCMDICTPATH environment variable. It is an error if no data dictionary can be loaded.

Depending on the command line options specified, the dcmdump utility will attempt to load character set mapping tables. This happens when DCMTK was compiled with the oficonv library (which is the default) and the mapping tables are not built into the library (default when DCMTK uses shared libraries).

The mapping table files are expected in DCMTK's <datadir>. The DCMICONVPATH environment variable can be used to specify a different location. If a different location is specified, those mapping tables also replace any built-in tables.

SEE ALSO

dump2dcm(1), dcmconv(1)

COPYRIGHT

Copyright (C) 1994-2025 by OFFIS e.V., Escherweg 2, 26121 Oldenburg, Germany.