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pngmeta(1)

NAME

   pngmeta  -  extract metadata from Portable Network Graphics (PNG) image
   files

SYNOPSIS

   pngmeta  [--soif]  [--html]  [--xrdf]  [--all]  [--quiet]   [--uri URI]
   [filename]

DESCRIPTION

   The  pngmeta filter outputs the metadata from Portable Network Graphics
   (PNG) format image files in one of these formats:

   1. Simple key: value

   2. SOIF format (as used by the Harvest system, version 1.4).

          As such it can be used as a Summarizer for the  Harvest  Essence
          system.  It could also be used by other indexers to extract data
          for indexing PNG images.

   3. HTML page With each element as an element in a descriptive (DL) list

   4. XML/RDF With each element as an RDF property on the source URI.

   In the absence of options, the program operates as a filter,  accepting
   input  from  stdin and sending output to stdout.  If a single file name
   is given, it is assumed to correspond to a PNG file, and is processed.

FORMAT OPTIONS

   --soif Format output using (Harvest) SOIF format.  This is the  default
          if the program is called PngImage.sum.

   --html Format  output in HTML, with each field/value as an element in a
          descriptive (DL) list.

   --xrdf Format output in RDF/XML, with each field/value as an element in
          an  rdf:Description  block  inside  the  outer  rdf:RDF  wrapper
          element.  If an XMLRDFDATA field is found, it is assumed  to  be
          RDF/XML  content  and  is  emitted  in  a second rdf:Description
          block.

OTHER OPTIONS

   --all  Output all the information about the image size, depth etc. even
          if not usually printed.

   --quiet
          Suppress  the output of the banner for plain text output.  --uri
          URI Set the URI that is used for the SOIF and  XML/RDF  outputs.
          By  default this will be the filename, or "stdin" if this is the
          program is used as a filter.

   --help Show a usage message

   --version
          Show the program and library versions

FILES

   pngmeta               executable

SEE ALSO

   gif2png(1),  libpng(3),  pbm(1),  pgm(1),   pngcheck(1),   pngtopnm(1),
   pnm(5), pnmgamma(1), pnmtopng(1), ptot(1), tiff2png(1), zlib(3)

   For information about Harvest and its SOIF format:

          http://harvest.cs.colorado.edu/

   For PNG

          http://www.libpng.org/pub/png/

   For libpng library

          http://www.libpng.org/pub/png/libpng.html
          http://libpng.sourceforge.net

   For zlib library

          http://www.zlib.net/

AUTHORS

   Version   1.11.    Dave   Beckett,   ILRT,   University   of   Bristol,
   http://purl.org/net/dajobe/

   The zlib(3) library required by  pngmeta  is  copyright  (C)  1995-1996
   Jean-loup Gailly and Mark Adler.

   Original UNIX manual page by R. P. C. Rodgers, U.S. National Library of
   Medicine ([email protected]).

                             10 March 1998                      PNGMETA(1)



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