path: root/static/v10/man1/bcp.1

.TH BCP 1 
.CT 1 graphics
.SH NAME
bcp \(mi reformat black-and-white picture files
.SH SYNOPSIS
.B bcp
[
.I option ...
]
[
.I file1
[
.I file2
]
]
.SH DESCRIPTION
.I Bcp
copies black-and-white (B&W) image
.I file1
to
.I file2,
optionally changing the file format and transforming the image.
If
.I file1
is a directory name,
then every leaf of its file tree is processed in turn; and, in this case,
if
.I file2
also is specified, it is made the root directory
of an isomorphic tree of output files.
If
.I file2
is not specified, all output is catenated to stdout.
.PP
.I Bcp
can copy among all the B&W
.IR picfile (5)
formats, and some others.
The default output format is 
.BR TYPE=ccitt-g4 .
Image transformations include trimming, translation, scaling, and rotation,
performed in that order (not in argument order).
.PP
Input files in
.IR picfile (5)
format must begin with an ASCII 
.BI TYPE= type
header line.
.I Types
supported both as input and output are:
.nr xx \w'\fLccitt-g4\ '
.TP \n(xxu
.B dump
One byte/pixel.
.B NCHAN=1
is required.
On input, the grey pixel values are thresholded
to B&W;
see option
.BR -T .
On output, black becomes 0 and white 255.
.TP
.B bitmap
One bit/pixel.
Essentially Sun rasterfile format, with a
.IR picfile (5)
header replacing the Sun binary header.
.TP
.B ccitt-g4
CCITT Group 4 FAX encoding, strongly compressive on printed text.
Also,
.B ccitt-g31
(Group 3, 1-dim)
and
.B ccitt-g32
(Group 3, 2-dim; see
.BR -k ).
.LP
Other supported
.I types
are:
.TP \n(xxu
.B binary
One bit/pixel encoding; obsolescent, but needed for old image archives.
Both input and output.
.TP
.B rle
Fast run-length encoding; obsolescent, but needed for old image archives.
Input or output, but not both.
.TP
.B pico
Same as
.BR dump .
Input only.
.TP
.B cdf
`Compound document format', used in AT&T FAX Connection product.
Input only.
Only the first of multiple pages is read.
.LP
Other formats not using a 
.BI TYPE= type
header, are:
.IR bitfile (9.5)
format;
PostScript bitmap format (output only); and
Sun rasterfile format (with the Sun binary header; output only).
.PP
The options are:
.TP \n(xxu
.B -B[io]
Read/write
.IR bitfile (9.5)
format (no 
.BI TYPE= type
header).
.TP
.B -M
Write 
.B TYPE=bitmap
format.
.TP
.B -P
Write Postscript bitmap format (Suns only).
.TP
.BI -R x , y
Force output resolutions to 
.I x,y
(pixels/inch).
If 
.BI , y
is missing, it is taken to be the same as
.I x.
Overrides
.BI -x x , y .
Requires a 
.BI RES= "x y
line in the header (but, see 
.BR -Z ).
.TP
.B -R=
Force the output resolution to be equal to the greater of
the input resolutions.
.TP
.B -S
Write Sun rasterfile format (no 
.BI TYPE= type
header; on Suns only).
.TP
.BI -T t
Threshold.
When reading 
.BR TYPE=dump ,
assign black to grey levels less than
.I t,
and white to others.
Default:
.BR -T128 .
.TP
.BI -Z x , y
Force input 
.BI RES= "x y.
.TP
.B -b
Write 
.B TYPE=binary
format.
.TP
.B -g4
.br
.ns
.TP
.B -4
Write 
.B TYPE=ccitt-g4
format.
Similarly, 
.B -g31
or
.B -31
and 
.B -g32
or
.BR -32 .
.TP
.BI -k n
Set the `k' for 
.B ccitt-g32
encoding on output (default
.BR -k4 ).
.TP
.BI -o x , y
Offset (translate) the image by 
.I x,y
pixels.
The width and height of the picture are not changed.
.TP
.B -p
Write 
.B TYPE=dump NCHAN=1
format.
Map black to 0, white to 255.
.TP
.B -r
Write 
.B TYPE=rle
format.
.TP
.B -tl
Rotate the image to bring the left edge of the page to the top.
Set top-left corner of the rotated
image at the top-left corner of the image.
.TP
.BI -t d
Rotate the image 
.I d
degrees counterclockwise about its center.
.I d
is a real number.
.TP
.BI -w l,t,r,b
Specify window (trim the image):
.I l,t
is the left-top corner and 
.I r,b
the right-bottom corner measured in pixels.
If the new margins are outside the original picture,
the new area is set to white.
An argument given as
.L %
leaves the edge unchanged.
.TP
.BI -x x , y
Expand/contract (scale) the image, by real factors 
.I x
and
.I y.
If
.BI , y
is missing,
.I y
is taken to be the same as
.I x.
May be overridden by 
.BI -R x , y.
Requires a 
.BI RES= "x y
line in the header (but, see 
.BR -Z ).
.SH SEE ALSO
.IR cscan (1),
.IR imscan (1),
.IR ocr (1),
.IR pico (1),
.IR picfile (5)
.br
CCITT facsimile coding standards Rec. T.4(1988) and T.6(1988).
.SH BUGS
Concatenated pages are supported, but only if each new page has a complete
header.
.br
Scaling is accomplished by naive replication/deletion of pixels.
.br
Rotation by small angles exhibits aliasing effects, and is slow.
.br
Rotations
.B -tr
and
.B -tb
are unfinished.
.br
CCITT FAX `uncompressed' (or, `transparent') mode is not implemented.
.br
Postscript output is useful only for small images.
.br
.BI WINDOW= "l t r b
where
.I l
or
.I t
is non-zero
may not be handled correctly for every combination of file types.
.br
.B TYPE=rle
can't be both input and output.
.br
Should be merged with T. Duff's
.I pcp.