.\"------------------------------------------------------------
.\" Id - set Rv,revision, and Dt, Date using rcs-Id tag.
.de Id
.ds Rv \\$3
.ds Dt \\$4
..
.Id $Id$
.\"------------------------------------------------------------
.TH mgtic 1 \*(Dt CITRI
.SH NAME
mgtic \- textual image compression.
.SH SYNOPSIS
.B mgtic
.B \-e
[
.B \-L
]
[
.B \-Q
]
[
.B \-X
]
.I libraryfile
.I infile
.if n .ti +9n
[
.I \>compressed\-outfile
]
.nf
or
.fi
.B mgtic
.B \-d
[
.B \-L
]
[
.BI \-X " libraryfile"
]
.I compressed-infile
.if n .ti +9n
[
.I \>outfile
]
.SH DESCRIPTION
This is the main routine in the
.B mgtic
system.
.B mgtic
is used to
processes a series of files, and by using the
.I libraryfile
produced by
.BR mgticbuild (1),
compresses input files with respect to the marks contained in the
library.  On the CCITT test faxes, lossless mode achieved around 20:1
compression, and lossy, around 40:1 compression.  On more textual
images, the amount of compression is determined by the resolution of
the original file, and the amount of noise in the image.  By default,
.B mgtic
will reconstruct a lossy version of the image.  This
can be changed to lossless by using the
.B \-L
option.
.SH OPTIONS
Options may appear in any order, but must come before the input
filenames.
.TP "\w'\fB\-X\fP \fI[libraryfile]\fP'u+2n"
.B \-h
This displays a usage line on
.IR stderr .
.TP
.B \-e
Encode
.I infile
with respect to the library.
.TP
.B \-d
Decodes
.IR compressed-infile
with respect to the library.
.TP
.B \-l
This specifies lossy mode, and is the default mode for (de)compression.
Do not generate the residue.  If used in encoding mode, does not store
the residue in the output.  If used in decoding mode, the residue (if
it exists) is ignored.
.TP
.B \-L
Use lossless mode for (de)compression, which generates the residue.
If used in encoding mode, this stores the residue in the compressed
output.  If used in decoding mode (assuming the residue is present),
this allows the original file to be recovered exactly.
.TP
.BI \-R\  filename
Stores the residue as an external file
.I filename
which could possibly be stored on another medium.  During
decompression, if the residue file specified does not relate to the
compressed file, the resulting decompressed image will be a mess.
Note that only the width and height of the residue image is checked.
.TP
.BI \-Q
Uses a quicker form of compression.  This option decreases the time
spent looking for a good match during encoding.  On average this
option decreases compression ratios, but increases compression speed.
.TP
.BI \-X " [libraryfile]"
Use an external library file, instead of (de)compressing the library
within the normal stream.  When decoding, the
.B \-X
option must be followed by the
.IR libraryfile .
.SH "SEE ALSO"
.na
.BR mg (1),
.BR mg_compression_dict (1),
.BR mg_fast_comp_dict (1),
.BR mg_get (1),
.BR mg_invf_dict (1),
.BR mg_invf_dump (1),
.BR mg_invf_rebuild (1),
.BR mg_passes (1),
.BR mg_perf_hash_build (1),
.BR mg_text_estimate (1),
.BR mg_weights_build (1),
.BR mgbilevel (1),
.BR mgbuild (1),
.BR mgdictlist (1),
.BR mgfelics (1),
.BR mgquery (1),
.BR mgstat (1),
.BR mgticbuild (1),
.BR mgticdump (1),
.BR mgticprune (1),
.BR mgticstat (1).