NAME¶
dcmcjpls - Encode DICOM file to JPEG-LS transfer syntax
SYNOPSIS¶
dcmcjpls [options] dcmfile-in dcmfile-out
DESCRIPTION¶
The
dcmcjpls utility reads an uncompressed DICOM image
(
dcmfile-in), performs a JPEG-LS compression (i. e. conversion to an
encapsulated DICOM transfer syntax) and writes the converted image to an
output file (
dcmfile-out).
PARAMETERS¶
dcmfile-in DICOM input filename to be converted
dcmfile-out DICOM output filename
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 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
JPEG-LS encoding options¶
JPEG-LS process:
+el --encode-lossless
encode JPEG-LS lossless only TS (default)
# This options selects the JPEG-LS lossless only transfer syntax
# and performs a lossless compression.
+en --encode-nearlossless
encode JPEG-LS near-lossless TS (NEAR: 2)
# This options selects the JPEG-LS lossy transfer syntax
# and performs a near-lossless compression.
JPEG-LS bit rate (near-lossless only):
+md --max-deviation [d]eviation: integer (default: 2)
defines maximum deviation for an encoded pixel
# This option specifies the maximum deviation for a single pixel from
# the original pixel value.
lossless compression:
+pr --prefer-raw
prefer raw encoder mode (default)
# This option enables the raw encoder. The raw encoder encodes the
# complete pixel cell as it was read from the source image without
# performing any modifications.
+pc --prefer-cooked
prefer cooked encoder mode
# This option enables the cooked encoder. The cooked encoder moves
# overlay data to separate tags (60xx,3000) and only encodes the
# stored bits in each pixel.
JPEG-LS compression:
+t1 --threshold1 [t]hreshhold: integer (default for 8 bpp: 3)
set JPEG-LS encoding parameter threshold 1
+t2 --threshold2 [t]hreshhold: integer (default for 8 bpp: 7)
set JPEG-LS encoding parameter threshold 2
+t3 --threshold3 [t]hreshhold: integer (default for 8 bpp: 21)
set JPEG-LS encoding parameter threshold 3
+rs --reset [r]eset: integer (default: 64)
set JPEG-LS encoding parameter reset
+lm --limit [l]imit: integer (default: 0)
set JPEG-LS encoding parameter limit
JPEG-LS interleave:
+il --interleave-line
force line-interleaved JPEG-LS images (default)
# This flag forces line-interleaved mode for the resulting image.
# In line-interleave mode each line from the source image is
# compressed separately for each component and then the next line
# is encoded.
+is --interleave-sample
force sample-interleaved JPEG-LS images
# This flag forces sample-interleaved mode for the resulting image.
# In sample-interleave mode each pixel's components are encoded before
# the next pixe is encoded.
+in --interleave-none
force uninterleaved JPEG-LS images
# This flag forces uninterleaved mode for the resulting image.
# In this mode, each of the image's components are completely encoded
# before the next component is handled.
+iv --interleave-default
use the fastest possible interleave mode
# This flag selects an interleave mode based on the source image's mode.
# If possible, the image is not converted to a different interleave mode.
encapsulated pixel data encoding options¶
encapsulated pixel data fragmentation:
+ff --fragment-per-frame
encode each frame as one fragment (default)
# This option causes the creation of one compressed fragment for each
# frame (recommended).
+fs --fragment-size [s]ize: integer
limit fragment size to s kbytes
# This option limits the fragment size which may cause the creation of
# multiple fragments per frame.
basic offset table encoding:
+ot --offset-table-create
create offset table (default)
# This option causes the creation of a valid offset table for the
# compressed JPEG fragments.
-ot --offset-table-empty
leave offset table empty
# This option causes the creation of an empty offset table
# for the compressed JPEG fragments.
SOP Class UID:
+cd --class-default
keep SOP Class UID (default)
# Keep the SOP Class UID of the source image.
+cs --class-sc
convert to Secondary Capture Image (implies --uid-always)
# Convert the image to Secondary Capture. In addition to the SOP Class
# UID, all attributes required for a valid secondary capture image are
# added. A new SOP instance UID is always assigned.
SOP Instance UID:
+ud --uid-default
assign new UID if lossy compression (default)
# Assigns a new SOP instance UID if the compression is lossy JPEG.
+ua --uid-always
always assign new UID
# Unconditionally assigns a new SOP instance UID.
+un --uid-never
never assign new UID
# Never assigns a new SOP instance UID.
output options¶
post-1993 value representations:
+u --enable-new-vr
enable support for new VRs (UN/UT) (default)
-u --disable-new-vr
disable support for new VRs, convert to OB
group length encoding:
+g= --group-length-recalc
recalculate group lengths if present (default)
+g --group-length-create
always write with group length elements
-g --group-length-remove
always write without group length elements
length encoding in sequences and items:
+e --length-explicit
write with explicit lengths (default)
-e --length-undefined
write with undefined lengths
data set trailing padding:
-p= --padding-retain
do not change padding (default)
-p --padding-off
no padding
+p --padding-create [f]ile-pad [i]tem-pad: integer
align file on multiple of f bytes
and items on multiple of i bytes
NOTES¶
The
dcmcjpls utility compresses DICOM images of all SOP classes. However,
dcmcjpls does not attempt to ensure that the compressed image still
complies with all restrictions of the object's IOD.
The user is responsible for making sure that the compressed images he creates
are compliant with the DICOM standard. If in question, the
dcmcjpls
utility allows to convert an image to secondary capture - this SOP class does
not pose restrictions as the ones mentioned above.
TRANSFER SYNTAXES¶
dcmcjpls supports the following transfer syntaxes for input
(
dcmfile-in):
LittleEndianImplicitTransferSyntax 1.2.840.10008.1.2
LittleEndianExplicitTransferSyntax 1.2.840.10008.1.2.1
DeflatedExplicitVRLittleEndianTransferSyntax 1.2.840.10008.1.2.1.99 (*)
BigEndianExplicitTransferSyntax 1.2.840.10008.1.2.2
(*) if compiled with zlib support enabled
dcmcjpls supports the following transfer syntaxes for output
(
dcmfile-out):
JPEGLSLosslessTransferSyntax 1.2.840.10008.1.2.4.80
JPEGLSLossyTransferSyntax 1.2.840.10008.1.2.4.81
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 behaviour 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 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
dcmcjpls 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 behaviour 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.
SEE ALSO¶
dcmdjpls(1)
COPYRIGHT¶
Copyright (C) 2009-2010 by OFFIS e.V., Escherweg 2, 26121 Oldenburg,
Germany.