DCHIST(1)						DICOM PS3 - DICOM image statistics						 DCHIST(1)

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 deter-
       mine 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 pro-
	      gram 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) 1993-2010. David A. Clunie DBA PixelMed Publishing. All rights reserved.

BUGS

DICOM PS3							  20 August 2007							 DCHIST(1)