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 (rodgers@nlm.nih.gov).
10 March 1998