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diff --git a/contrib/eqn2graph/eqn2graph.1.man b/contrib/eqn2graph/eqn2graph.1.man
new file mode 100644
index 0000000..c059190
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+++ b/contrib/eqn2graph/eqn2graph.1.man
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+.TH eqn2graph @MAN1EXT@ "@MDATE@" "groff @VERSION@"
+.SH Name
+eqn2graph \- convert an
+.I eqn \" generic
+equation into a cropped image
+.
+.
+.\" ====================================================================
+.\" Legal Terms
+.\" ====================================================================
+.\"
+.\" This documentation is released to the public domain.
+.
+.
+.\" Save and disable compatibility mode (for, e.g., Solaris 10/11).
+.do nr *groff_eqn2graph_1_man_C \n[.cp]
+.cp 0
+.
+.\" Define fallback for groff 1.23's MR macro if the system lacks it.
+.nr do-fallback 0
+.if !\n(.f           .nr do-fallback 1 \" mandoc
+.if  \n(.g .if !d MR .nr do-fallback 1 \" older groff
+.if !\n(.g           .nr do-fallback 1 \" non-groff *roff
+.if \n[do-fallback]  \{\
+.  de MR
+.    ie \\n(.$=1 \
+.      I \%\\$1
+.    el \
+.      IR \%\\$1 (\\$2)\\$3
+.  .
+.\}
+.rr do-fallback
+.
+.
+.\" ====================================================================
+.SH Synopsis
+.\" ====================================================================
+.
+.SY eqn2graph
+.RB [ \-format\~\c
+.IR output-format ]
+.RI [ convert-argument \~.\|.\|.]
+.YS
+.
+.
+.SY eqn2graph
+.B \-\-help
+.YS
+.
+.
+.SY eqn2graph
+.B \-v
+.
+.SY eqn2graph
+.B \-\-version
+.YS
+.
+.
+.\" ====================================================================
+.SH Description
+.\" ====================================================================
+.
+.I eqn2graph
+reads a one-line
+.MR @g@eqn @MAN1EXT@
+equation from the standard input and writes an image file,
+by default in Portable Network Graphics (PNG) format,
+to the standard output.
+.
+.
+.PP
+The input EQN code should
+.I not
+be preceded by the
+.B .EQ
+macro that normally precedes it within
+.MR groff @MAN1EXT@
+macros;
+nor do you need to have dollar-sign or other delimiters around the
+equation.
+.
+.
+.\" FIXME: How old?  This text hasn't been touched since 2008 at latest.
+.\" Older versions of
+.\" .I \%convert
+.\" will produce a black-on-white graphic; newer ones may produce a
+.\" black-on-transparent graphic.
+.
+.PP
+Arguments not recognized by
+.I eqn2graph
+are passed to the ImageMagick or GraphicsMagick program
+.MR convert 1 .
+.
+.
+By specifying these, you can give your image a border,
+.\" Transparent backgrounds are the default in 2018.
+.\" force the background transparent,
+set the image's pixel density,
+or perform other useful transformations.
+.
+.
+.PP
+The output image is clipped using
+.IR \%convert 's
+.B \-trim
+option to the smallest possible bounding box that contains all the black
+pixels.
+.
+.
+.\" ====================================================================
+.SH Options
+.\" ====================================================================
+.
+.B \-\-help
+displays a usage message,
+while
+.B \-v
+and
+.B \-\-version
+show version information;
+all exit afterward.
+.
+.
+.TP
+.BI \-format\~ output-format
+Write the image in
+.IR output-format ,
+which must be understood by
+.IR \%convert ;
+the default is PNG.
+.
+.
+.\" ====================================================================
+.SH Environment
+.\" ====================================================================
+.
+.TP
+.I \%GROFF_TMPDIR
+.TQ
+.I \%TMPDIR
+.TQ
+.I TMP
+.TQ
+.I TEMP
+These environment variables are searched in the given order to determine
+the directory where temporary files will be created.
+.
+If none are set,
+.I /tmp
+is used.
+.
+.
+.\" ====================================================================
+.SH Authors
+.\" ====================================================================
+.
+.I eqn2graph
+was written by
+.MT esr@\:thyrsus\:.com
+Eric S.\& Raymond
+.ME ,
+based on a recipe for
+.MR pic2graph @MAN1EXT@ ,
+by W.\& Richard Stevens.
+.
+.
+.\" ====================================================================
+.SH "See also"
+.\" ====================================================================
+.
+.MR pic2graph @MAN1EXT@ ,
+.MR grap2graph @MAN1EXT@ ,
+.MR @g@eqn @MAN1EXT@ ,
+.MR groff @MAN1EXT@ ,
+.MR convert 1
+.
+.
+.\" Restore compatibility mode (for, e.g., Solaris 10/11).
+.cp \n[*groff_eqn2graph_1_man_C]
+.do rr *groff_eqn2graph_1_man_C
+.
+.
+.\" Local Variables:
+.\" fill-column: 72
+.\" mode: nroff
+.\" End:
+.\" vim: set filetype=groff textwidth=72:
diff --git a/contrib/eqn2graph/eqn2graph.am b/contrib/eqn2graph/eqn2graph.am
new file mode 100644
index 0000000..2870d13
--- /dev/null
+++ b/contrib/eqn2graph/eqn2graph.am
@@ -0,0 +1,40 @@
+# Copyright (C) 2002-2020 Free Software Foundation, Inc.
+#
+# This file is part of groff.
+#
+# groff is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# groff is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# eqn2graph.am
+#
+
+eqn2graph_srcdir = $(top_srcdir)/contrib/eqn2graph
+bin_SCRIPTS += eqn2graph
+man1_MANS += contrib/eqn2graph/eqn2graph.1
+EXTRA_DIST += \
+  contrib/eqn2graph/eqn2graph.1.man \
+  contrib/eqn2graph/eqn2graph.sh
+
+eqn2graph: $(top_srcdir)/contrib/eqn2graph/eqn2graph.sh
+	$(AM_V_GEN)sed -e "s|[@]g[@]|$(g)|g" \
+	    -e "s|[@]VERSION[@]|$(VERSION)|" \
+	    -e $(SH_SCRIPT_SED_CMD) $(eqn2graph_srcdir)/eqn2graph.sh \
+	    >$@ \
+	&& chmod +x $@
+
+
+# Local Variables:
+# fill-column: 72
+# mode: makefile-automake
+# End:
+# vim: set autoindent filetype=automake textwidth=72:
diff --git a/contrib/eqn2graph/eqn2graph.sh b/contrib/eqn2graph/eqn2graph.sh
new file mode 100644
index 0000000..3e9c374
--- /dev/null
+++ b/contrib/eqn2graph/eqn2graph.sh
@@ -0,0 +1,108 @@
+#! /bin/sh
+#
+# eqn2graph -- compile EQN equation descriptions to bitmap images
+#
+# by Eric S. Raymond <esr@thyrsus.com>, July 2002
+#
+# In Unixland, the magic is in knowing what to string together...
+#
+# Take an eqn equation on stdin, emit cropped bitmap on stdout.
+# The eqn markup should *not* be wrapped in .EQ/.EN, this script will do that.
+# A -format FOO option changes the image output format to any format
+# supported by convert(1).  All other options are passed to convert(1).
+# The default format is PNG.
+#
+# This is separate from pic2graph because pic processing has some weird
+# clipping effect on the output, mangling equations that are very wide 
+# or deep.  Besides, this tool can supply its own delimiters.
+#
+
+# Requires the groff suite and the ImageMagick tools.  Both are open source.
+# This code is released to the public domain.
+#
+# Here are the assumptions behind the option processing:
+#
+# 1. None of the options of eqn(1) are relevant.
+#
+# 2. Many options of convert(1) are potentially relevant, (especially
+# -density, -interlace, -transparency, -border, and -comment).
+#
+# Thus, we pass everything except -format to convert(1).
+#
+convert_opts=""
+convert_trim_arg="-trim"
+format="png"
+
+while [ "$1" ]
+do
+    case $1 in
+    -format)
+	format=$2
+	shift;;
+    -v | --version)
+	echo "GNU eqn2graph (groff) version @VERSION@"
+	exit 0;;
+    --help)
+	echo "usage: eqn2graph [ option ...] < in > out"
+	exit 0;;
+    *)
+	convert_opts="$convert_opts $1";;
+    esac
+    shift
+done
+
+# create temporary directory
+tmp=
+for d in "$GROFF_TMPDIR" "$TMPDIR" "$TMP" "$TEMP" /tmp
+do
+    test -n "$d" && break
+done
+
+if ! test -d "$d"
+then
+    echo "$0: error: temporary directory \"$d\" does not exist or is" \
+        "not a directory" >&2
+    exit 1
+fi
+
+if ! tmp=`(umask 077 && mktemp -d -q "$d/eqn2graph-XXXXXX") 2> /dev/null`
+then
+    # mktemp failed--not installed or is a version that doesn't support those
+    # flags?  Fall back to older method which uses more predictable naming.
+    #
+    # $RANDOM is a Bashism.  The fallback of $PPID is not good pseudorandomness,
+    # but is supported by the stripped-down dash shell, for instance.
+    tmp="$d/eqn2graph$$-${RANDOM:-$PPID}"
+    (umask 077 && mkdir "$tmp") 2> /dev/null
+fi
+
+if ! test -d "$tmp"
+then
+    echo "$0: error: cannot create temporary directory \"$tmp\"" >&2
+    exit 1
+fi
+
+# See if the installed version of convert(1) is new enough to support the -trim
+# option.  Versions that didn't were described as "old" as early as 2008.
+is_convert_recent=`convert -help | grep -e -trim`
+if test -z "$is_convert_recent"
+then
+    echo "$0: warning: falling back to old '-crop 0x0' trim method" >&2
+    convert_trim_arg="-crop 0x0"
+fi
+
+trap 'exit_status=$?; rm -rf "$tmp" && exit $exit_status' EXIT INT TERM
+
+# Here goes:
+# 1. Add .EQ/.EN.
+# 2. Process through eqn(1) to emit troff markup.
+# 3. Process through groff(1) to emit Postscript.
+# 4. Use convert(1) to crop the Postscript and turn it into a bitmap.
+read equation
+(echo ".EQ"; echo 'delim $$'; echo ".EN"; echo '$'"$equation"'$') | \
+	groff -e -Tps -P-pletter > "$tmp"/eqn2graph.ps \
+	&& convert $convert_trim_arg $convert_opts "$tmp"/eqn2graph.ps \
+	   "$tmp"/eqn2graph.$format \
+	&& cat "$tmp"/eqn2graph.$format
+
+# End