Table of Contents
xwpick - pick images from an X11-screen and store in files
xwpick
[-local] [-window id] [-gray] [-reverse] [-pause] [-format frmt] [<file>]
Xwpick
lets you pick an image from an arbitrary window or rectangular area of
an X11-server and write it to a file in a variety of formats.
The output
format is defined whether by the -format option or by the extension in the
file name. Possible formats/extentions are:
- ps
- An Encapsulated PostScript
file with a compressed image. The image is centered, rotated and scaled
to fill the maximum space on a page. It is displayed in color on viewers
and printers that support color Postscript, otherwise it is displayed as
grayscale. This format is convenient for transparency preparation.
- eps
- Also
an Encapsulated PostScript file with a compressed image, but the image
is only centered, not rotated and scaled. It is intended for insertion into
a document.
- epsi
- The same as eps, but contains a black and white preview.
- gif
- Graphics Interchange Format (GIF). Use this format when you want to
keep files or transfer them to other computers. It is also convenient for
visualisations, for example, with xv by John Bradley.
- pcx
- PCX format for
IBM PC.
- pict
- PICT format for Macintosh. It is intended for image transfer
on Macintosh, but GIF format is also convenient for this purpose (see Macintosh
GIFConverter by Kevin A. Mitchell).
- ppm
- PPM format from the PBM Plus library
by Jef Poskanzer. Use it and a routine from the PBM Plus library if you
wish to have the image in a format not mentioned above.
The main feature
of xwpick is that it uses the Lempel-Ziv Welch (LZW) compression scheme
for image encoding in Postscript, thus producing very compact files (4-5
times less than files produced with Run-Length encoding (RLE) and 10-20 times
less than files produced without compression)
When xwpick is
invoked, the user sees a blinking rectangle surrounding the contents of
the window in which the mouse pointer is currently placed. When the mouse
is moved to a different window, the perimeter automatically changes to
the size of the new window. If the mouse pointer is placed on the Window
Manager border of a window, then the blinking rectangle will surround the
window together with the Window Manager border. To select the image inside
the blinking rectangle it is sufficient to click the left mouse button.
If a user-defined perimeter is required, then hold down the left mouse button
to choose the first corner of the perimeter and then drag the mouse to
define the opposite corner. The blinking rectangle will expand with the
movement of the mouse.
If it is required to produce some changes inside
the selected area just before outputing to a file, for example, to change
the palette or display a pop-up menu, then the -pause option can be used.
- -local
- When -local is in the parameter list, xwpick picks an image
from the window under the mouse pointer. This option is intended to pick
images from pop-up menus, which are on the screen only when a mouse button
is pressed and disappear immediately after the button is released.
- -window
id
- Pick an image from the window with integer identifier equal to id. The
identifier for a window can be obtained with the X Window program xwininfo.
To pick the entire screen (root window) the user may use the word root
as an identifier.
- -gray
- Transfer the image to grayscale. This option can be
used to optimize output on level 1 gray scale PostScript printers.
- -reverse
- Transfer the image to reverse colors. This option can help you to save the
toner on your printer in case when the image is too dark.
- -pause
- Do not output
the image till the <SPACE> bar will be pressed. This option allows to use
the mouse to produce some changes inside the selected image just before
outputing to a file.
- -format frmt
- Set output format. The format is defined
by frmt string. If this option is omited, then the output format is defined
by the extension in the file name. Possible frmt strings/extensions are:
ps, eps, epsi, gif, pcx, pict, ppm. In case when -format is in the parameter
list and a file name is omited the output is directed to the standard output.
This is the simplest form of use. You will be prompted
to input a file name.
- xwpick image.ppm
ppmtoxpm image >image.xpm
This is an example of how to get an image in X11
pixmap format. First you pick the image from the screen into the file image.ppm
and then convert it using the ppmtoxpm routine from the PBM PLUS library.
This is an example of how to pick the image of a
pop-up menu window and store it in a file as encapsulated Postscript with
preview.
- xwininfo
xwpick -w 0x8000c1 -g clock.ps
This is an example of how to pick an image
from the window by the window's identifier. First you find the identifier
using the xwininfo command and then pick an image from the window and
store it in a Postscript file as a grayscale image.
- xwpick -window root -format
ps | lpr
This is an example of how to send an image of the root window directly
to the printer.
Evgeni Chernyaev chernaev@mx.ihep.su
xwd(1)
,
xv(1)
, xgrabsc(1)
, XtoPS(1)
, xwininfo(1)
, ppm(5)
Copyright (C)
1993, 1994 by Evgeni Chernyaev.