PC Plus HelpDesk - issue 269
 |
This month, Paul Grosse gives you more
insight into some of the topics dealt with in HelpDesk.
From the pages of HelpDesk, I look at:
- Scaling large images;
- Video screen capture;
- Burning ISOs;
- Linux with Wine; and,
- Killing windows.
|
 |
HelpDesk
Scaling large images
If you regularly
print out large image files from Internet Explorer, you
might encounter problems with the image running off the
right and side and the bottom, rendering the printout
useless. So, how do you get it to print out the whole
image?
This problem used to occur when people bought a new
monitor and changed the screen resolution - Internet
Explorer altering the size of the printed image so that
it was bigger.
|
However,
you can get around this without changing resolutions just
by going into print preview - click on the down-arrow to
the right of the printer icon on the toolbar then select
'Print Preview...'.In that view, you have the option
to adjust the page margins by dragging the markers that
appear just outside the edge of the page (you need to
have the full page view to do this because they disappear
if you select the full page width view), or, you can
change the scale of the image.
|
Just
select 'Shrink To Fit' from the drop-down menu and your
image will fit on the page.At print resolutions of
300dpi, a scale change of a few per cent is not going to
cause moire-like banding on the printout.
|
Video
screen capture
Video screen capture on Linux is easy and, of course,
free with Istanbul.
Capturing video to demonstrate something is always
more effective than just static pictures alone - I bet
you can't wait until the pages of PC Plus are in such a
form.
On Linux (here in Ubuntu), there is a program called
Istanbul that will record an area of the screen for you.
Start it by clicking on 'Applications', 'Sound &
Video', 'Istanbul'.
Right-click on the red dot on the taskbar to see the
options and select the area to record - this appears as a
red rectangle as you drag it and if you get it wrong, you
can always reselect it.
|
When
you are ready, click on the red button to start the
recording process and get on with whatever you are
supposed to be doing, whether it is demonstrating how to
get the computer to do something unusual or displaying
your outstanding abilities at Tetris.When you have
finished, click on the stop button (the square in the
taskbar that the red circle became) and save the video to
the place of your choice.
|
The
video is saved at 10 frames per second using the Ogg
Theora video codec which has a mime type of
'video/x-theora+ogg' for your web pages.Ogg is
included in the upcoming HTML5 standard and it is worth
noting that Ogg has no issue with patents or patent
royalties (thanks to an irrevocable and free license) so
you can put them on your website freely.
If you want to look at the video (it illustrates the
use of the video rather than my abilities at playing
Tetris) then just click here
to open up a directory in a new window.
|
Burning ISOs
If you are trying to
burn an ISO image file (such as those for KNOPPIX or
OpenBSD and so on) to CD under Windows Vista - you might
find it tempting to insert the CD and then drag the ISO
file and drop it onto the folders directory of the CD in
Windows Explorer.
However, when you have finished burning it and reboot
the machine, it will look at the CD and then the BIOS
will just take you straight to where it normally goes -
usually Windows (even though the BIOS is set to boot from
the CD first). So, what's going wrong?
The CD/DVD support on Windows is very rudimentary and
saving files is made so easy that it seems the natural
thing to drag an ISO disc image onto File Manager and
think that it has done what you want it to.
|
| However there is a subtle difference. When you save a file, you put it
into a file system that Windows has already constructed
for you on the CD (as in the 'CD/DVD for saving data'
example in the diagram on the right).
An ISO image (as in the '.ISO file' example in the
diagram) already has that structure within it and is
literally an image of the whole CD, including any boot
files that are necessary.
All that the CD burner program has to do is to copy
it, sector for sector onto the CD (which is how it
appears in the last diagram on the right - the way it
should be). That way, on boot up, when the BIOS needs to
read a sector from it, it does so directly and will boot.
If you just save it as a file (as in the 'CD/DVD with
.ISO file "saved"' diagram on the right), the
BIOS will not see the ISO's boot files it needs and go
onto the installed hard drives to look for an OS or
bootloader.
ISOs are usually used to produce installation discs
for installing UNIX-like OSes such as Linux, Solaris, and
*BSD so Windows would have no need for the capability
because Windows is the only OS you will ever need.
Apparently.
|
You can
install a proper Windows executable CD/DVD ISO burning
program for free.There is a list of ISO burners at www.windowsmarketplace.com/results.aspx?text=.iso&WT.mc_id=iso
.

If you are lucky enough to know someone with Linux
already installed, you can use the K3B CD/DVD burner
which is very easy to use.
|
Linux
with Wine
Using Windows programs in Linux is not as difficult as
it sounds, thanks to the emulators that you can use.
The best known of these is 'Wine'.
To install a Windows program from a browser (here,
we'll use Firefox), all you do is click on the download
link and when Firefox opens the file, select 'Open with
wine (default)' and click on 'OK'.
The program then runs and installs itself as it would
on Windows, all from a pseudo c:\ directory in your home
'.wine' directory if you want to find it.
From the main menu, the program appears under the
'Applications', 'Programs', program-name.
If your program runs as full screen, as many games do,
but you want to run it in a window (as the program in the
screenshot on the right is doing), just press
[Alt][Enter] as you would if you were running Windows.
We'll leave it as an exercise for you to see if you
think that programs run with higher frame rates under
Linux with Wine.
Also, as you are running with the security of Linux,
if the program turns out to be malicious, it only affects
resources that you have access to, limiting it
effectively to your own home directory.
|
Killing windows
If you sometimes get a window that won't die, you can
kill it off by using things other than the little 'X'
button that is usually in the top right of the Window, on
the title bar.
If you don't know, from the command line, you can grep
a list of processes for a process (here, hypothetically
called 'progname') by name by entering ...
ps aux | grep progname
... or, more concisely by using the dedicated function
pgrep like so ...
pgrep progname
... which will give you a list of PIDs from which you
can choose one to kill.
Alternatively, if you have a process that is gobbling
up processor time, you can see it by using 'top' which
will display the process list according to how much
processor time the programs are using.
Pressing 'K' will freeze the list and allow you to
kill the process by typing in its PID.
However, if a program
has multiple windows or you have several copies of the
same program running, there is a more explicit way of
doing this.
At the command line, type 'xkill' and the mouse will
change to the skull and crossbones, allowing you to click
on the offending window and kill that program.
The only thing that can go wrong is that the program
terminates itself and the window disappears before you
have a chance to kill it thus leaving you with an armed
and dangerous mouse that will kill the first thing it
clicks on. If you think this might happen, you can always
open up another window beforehand (such as a terminal or
text editor) so that you can click on that if necessary.
|
Back to PC Plus Archive Index Page
|