JVWbg.exe is a utility for use in creating bitmaps
suitable for use as desktop wallpaper or lockup screens.
The following discussion assumes you will be creating
wallpaper.  Everything is also valid for use in creating
a lockup screen, except the -r parameter will not be used.

There are two required parameters, an input file and
an output file.  Naturally enough, the input file must be
an image file, in any format that JView supports, that
you wish to be converted for use as wallpaper.  You also
need to specify an output file.  This is because the wallpaper
setting needs to reference an actual file, so that each time
you restart OS/2 the file can be loaded.  To see what file
(if any) you are currently using, open the settings notebook
for the desktop.  Go to the Background tab.  You will see
a listbox labeled File:.  The file highlighted is what you
are currently using.  One useful way of using JVWbg is
to always use the same output file, overwriting the old one
each time.

In addition to the two file names, there are two optional parameters
that can be used.  They are -s  and -r.

-s will cause the image to fill the screen as much as possible but
still maintain the correct aspect ratio.

-r will cause the current background to be replaced immediately. 
Otherwise you need to reboot OS/2 for the change to take effect,
assuming you are overwriting the currently defined file for use
as a background.  If you are creating a lockup screen, you will
not use this parameter, the lockup image is only read when the
system blanks the screen, so changing files can take place
without rebooting the machine.

Input and output files should have a full path specified.

Here are some samples of how JVWbg could be called.

JVWbg d:\images\jpegs\favorite.jpg c:\os2\bitmaps\background.bmp
*This would simply create the file c:\os2\bitmaps\background.bmp.
*The current desktop background would remain unchanged even
*if the background setting was to this file.  However, if this was the
*case once OS/2 reboots, the image will be displayed.

JVWbg -r d:\favorite.jpg c:\os2\bitmaps\background.bmp
*This would be exactly as above, except the image would be
*resized to fit the current screen dimensions.

JVWbg -r -s d:\favorite.jpg c:\os2\bitmaps\background.bmp
                                          or
JVWbg -rs d:\favorite.jpg c:\os2\bitmaps\background.bmp
*This would be exactly as above, except now the image would
*immediately be used as the desktop wallpaper.

JVWbg d:\favorite.jpg background.bmp
*Because no path was indicated for the output file, it would be
*placed in the directory where JVWbg was started from. 


There is a companion file for this executable, called bkgrnd.cmd.
It is a REXX routine that allows you to randomly create backgrounds
for your desktop.
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