NAME

       dchist - ACR/NEMA DICOM PS3 ... DICOM PS3 - DICOM image statistics

SYNOPSIS

       dchist [ -h|histogram ] [ -csv ] [ -withhighbits|highbitsonly ] [ -v|verbose ] [ -filename
                 ]

DESCRIPTION

       dchist reads the named dicom or acr-nema input file and describes the  statistics  of  the
       image pixel data. The primary intent is to determine the zero order entropy of the image.

       The description and verbose output go to standard error.

       The  basic  input  switches  are described in dcintro(1). Options specific to this program
       are:

       -h|histogram
              Display table of pixel value, frequency, probability, contribution  to  zero  order
              entropy, and cumulative zero order entropy. May generate a LOT of output !

       -csv
              Display  only  a  comma separated value pair of pixel value and frequency, one line
              per value, e.g., for import into a statistical program or spreadsheet

       -withhighbits
              Include as well the values that are above Bits Stored and  within  Bits  Allocated,
              such  as  might  be  overlay  bits (regardless of whether or not there are any 60xx
              group elements).

       -highbitsonly
              Use instead the values that are above Bits Stored and within Bits  Allocated,  such
              as  might  be  overlay  bits,  and  treat  all valid pixel values below Bits Stored
              inclusive as zero (regardless of whether or not there are any 60xx group elements).

       -v|verbose
              Display byte offset from file start and message start,  in  hexadecimal,  and  dump
              contents while reading and once read.

       -filename
              Show  the  name of the file supplied in the arguments; a hyphen will be reported if
              no filename was supplied.

ENVIRONMENT

EXAMPLES

       % dchist expmeta.dc3
       9.02366 Zero order entropy (bits per pixel)
       0x0     Smallest symbol value
       0       Smallest symbol length (bits)
       0x6e9   Largest symbol value
       11      Largest symbol length (bits)

       % dchist -h expmeta.dc3
       [0x0]   392 p=0.00598145  e=0.0441747   cum=0.0441747
        ...
       [0x6e9] 1   p=1.52588e-05 e=0.000244141 cum=9.02366

       9.02366 Zero order entropy (bits per pixel)
       0x0     Smallest symbol value
       0       Smallest symbol length (bits)
       0x6e9   Largest symbol value
       11      Largest symbol length (bits)

FILES

SEE ALSO

       dcstats(1), dcintro(1)

AUTHOR

       Copyright (c) 1993-2022, David A. Clunie DBA PixelMed Publishing. All rights reserved.

BUGS