Scroll to navigation

dcmdump(1) OFFIS DCMTK dcmdump(1)


dcmdump - Dump DICOM file and data set


dcmdump [options] dcmfile-in...


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.


dcmfile-in  DICOM input file or directory to be dumped


general options

-h --help
print this help text and exit
print version information and exit
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


+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
# not available on Windows systems
-C --no-color
do not use any ANSI escape codes (default)
# not available on Windows systems 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)


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.


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.


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).


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.


dump2dcm(1), dcmconv(1)


Copyright (C) 1994-2022 by OFFIS e.V., Escherweg 2, 26121 Oldenburg, Germany.

Fri Apr 22 2022 Version 3.6.7