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PC Plus HelpDesk - issue 230
This month, Paul Grosse gives you more insight into
some of the topics dealt with in HelpDesk and HelpDesk
Extra
From the pages of HelpDesk, we look at:
- Watermarks in PDF Documents;
- XMMS Skins (including file); and,
- CapsLock No More (file).
From HelpDesk Extra, we look at OGG to MP3
conversion (personal stereos):
- Why convert to MP3?;
- Lame;
- ogg2mp3;
- CPAN - Perl modules; and,
- Future-proofing.
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HelpDesk
Watermarks in PDF Documents
There are a number of utilities on the Internet that
will allow you to 'print' to a special 'printer'.
However, not all of these will allow you to print
watermarks in your documents. Doing a quick search using
Google will show some but there is a better
alternative...
The 'printer' drivers work by pretending to be a
printer - your word processor or whatever you are using
sends the data that is required to what it thinks is a
printer but instead, the driver collects the data and
turns it into a PDF file. This emulates the process on
UNIX/Linux/*BSD systems where you can print from any
program that will print to the PDF file driver. So, what
is the better alternative?
OpenOffice.org will print directly to PDF including
any watermarks without you having to have a special
printer driver. This is especially useful in Windows
environments where a PDF printer is not part of the
normal system. In short, anything you can put on a page
can be printed to PDF with OpenOffice.org.
If you are concerned about compatibility issues using
OpenOffice.org, it will import your legacy Microsoft
files and print those out for you although you will
probably like to go over to OOo eventually for its
licensing and cost benefits.
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XMMS Skins
XMMS is skinable and you can make your own if you
really want to. All you need to do to add a skin is to go
to the xmms skins download page at http://www.xmms.org/skins.php
and download those of your choice. Save the file in
/usr/share/xmms/Skins/ and they will show in the skins
browser - there is no need to unzip them.
The one on the right is based on the OS X theme on the
Mac but you are not limited to this.
If you do want to
make one of your own, you can look at the image files in
the tar.gz file. You will also need to look at the files
that contain the rgb information for the analyser and
scope and set them - one is in hex which is easy to
separate into rgb values and the other has the rgb values
as decimal. One tool for getting just the right colours
is the GIMP which has the colour picker and also, if you
click on the colour in the palette, you will get a colour
dialogue which should give you what you need.
You can make your own design as original as you like
but just to show you what can be done by changing as
little as possible, I made the variant on the right, for
*BSD.
I started off by cloning out Tux and replacing him
with the BSD Daemon using The GIMP. Then, I rotated the
colours so that it took on the red scheme that you can
see on the right.
You can get that skin by clicking on this
link and following the instructions at the beginning.
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CapsLock No More
If you double-click on the file
KillCapsLock.reg in this link, it should open up with
Regedit and add to your system so that the Caps Lock Key
will no longer lock - it will work like the ordinary
shift key. This is XP only as far as we know but if you
throw caution to the wind and take the devil-may-care
line, you might want to try it with Windows 2000 but
don't come crying to us.
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HelpDesk Extra
Why convert to MP3?
It is true that MP3 has little of the quality that Ogg
Vorbis has for the same file size - in fact, if you
compress the same wav file using MP3 and Ogg Vorbis, you
will always end up with a larger MP3 file for a similar
quality.
One other thing to
note is that MP3 is a lossy compression in a similar way
to Ogg Vorbis. However, each of these compression
techniques throws away a different part of the data file
to the other so, if you were to compress a sound file
using Ogg Vorbis and then expand that file and
re-compress it using MP3, the resulting file would be
doubly degraded. Note that this would happen whichever
one you used first.
Another point worthy of note is that MP3 has a patent
on it so every time you download an MP3 file, some of
your money goes to the patent owners. Ogg Vorbis was
designed so that there were no patents to infringe and no
fees to pay.
So, if Ogg Vorbis is better than MP3 and it is free,
why convert to MP3 instead of Ogg Vorbis? The answer is
simply that, at the moment, the people who make personal
stereos of the USB variety generally do not include Ogg
Vorbis as a file type that can be played. If you are
going to get one of these players, you should try to get
one that has Ogg Vorbis compatibility on it already or
get one that you can update the BIOS with so that in the
future, it will be able to play Ogg Vorbis files - sooner
or later, the music industry will cotton on to the fact
that they can make better quality, smaller files that
don't cost as much by abandoning MP3 for an open format
like Ogg Vorbis.
So, if they are both lossy, why convert from Ogg
Vorbis to MP3? If you have already converted your songs
to Ogg Vorbis and intend to play them on a personal
stereo, any quality loss caused by re-conversion is not
going to be that significant. If you have songs that you
have not yet converted to Ogg Vorbis, you should convert
them to MP3 directly - also make an Ogg Vorbis copy so
that you can stream it across your home LAN as this works
better than MP3 does.
To create an MP3 file - either from an Ogg Vorbis file
or a wav file, you will need an encoder like Lame.
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Lame
Lame encodes .wav format files to .mp3 but first of
all you need to get a copy. You will find that pretty
much all of the pre-compiled versions are for Windows or
a specific Linux distribution which I would recommend you
try first. If the pre-compiled version does not work on
your distribution, it is fairly easy to compile your own
as follows....
First of all, you need to download the source from http://lame.sourceforge.net/download/download.html
and be sure to click on the 'important message from the
RIAA' link and read it.
Next, go back and click on the 'Source Code: Click
here ...' link and then on the 3.96.1 (or higher) link
that ends with '.tar.gz', which will take you to the
SourceForge.net download server.
Choose a mirror and click on the download link. The
'.tar.gz' should be saved to wherever you decided to put
it (putting it on the Desktop makes things fairly
straightforward). The following is reasonably easy if you
are using a windows manager such as KDE.
Right-click on the tar.gz and in the drop-down menu,
select 'Ark' or 'Open with...'> 'Utilities'>'Ark'.
In Ark, you will see a list of all of the files and
directories in the archive. Click on 'Action'>
'Extract...' and choose somewhere to extract the files
such as your bin directory. Click on okay and close Ark.
Open up Konqueror at the location where you saved the
extracted archive and then, in the pane with all of the
files in it, right-click on a blank area and on the menu,
click on 'Open Terminal Here'. Next, at the command
prompt, type ...
./configure
make
make install
... which will configure, compile and install the
program. This process might take a few minutes but you
know that at the end of it, you will have the MP3 encoder
compiled for your own system rather than having some
generalised version of it that might have system specific
incompatibilities within it.
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ogg2mp3
Now that you have your .mp3 encoder, you need to have
a program that will take your .ogg files and convert them
to .mp3. Usually, if you want to perform a conversion
from one format to another, you can usually find a
program with a name made up of the two file extensions
with the number two between. A quick look on Google shows
a program (a Perl script by Mark Draheim) called
'ogg2mp3' (http://amor.cms.hu-berlin.de/~h0444y2j/linux.html)
which has a download around half way down the page
(Files... Just the script).
Save the script somewhere on your system -- the root
directory of where you keep your .ogg files will make the
following easier -- and make sure that it is executable.
Next, open up a command shell at that location and
type...
./ogg2mp3 *
... and, if all has gone according to plan, it will
start munching its way, recursively through your
directories of .ogg files, translating them to the same
file name but with the .mp3 extension.
However, you will probably find that you need to do
more first and the clues are in the ogg2mp3 program
script. If you open it up in KWrite or Kate, you will see
that there are a number of things that need to be
present: the files 'ogginfo' and 'ogg123' need to be in
'/usr/bin/' which they already should be as you have
generated your own .ogg files already; and, you need to
make sure that 'lame' which you have just compiled is
also in '/usr/bin/', or that you alter the line in the
Perl script that tells the script where to expect to find
it. If you are missing a Perl module, look at the sidebar
on the right.
With all of the locations correct and the correct
modules installed, ./ogg2mp3 will now work away
recursively (although not necessarily in what we might
think is a logical order) until they are all converted.
If you have a fairly extensive collection, you might want
to think more about preparing a four course meal than
making a cup of coffee whilst you wait.
Once it is finished, you will have an .mp3 and .ogg
copy of each song in your directories. To make using your
MP3 player easier, it is best to have the MP3 files in
separate directory so, if you have .ogg and .mp3
directories with all of the album directories within
those, you can use them easier. Using the MP3 player is
now a matter of: plug it into the USB port; mount it
(usually as sda1 or similar); open up Konqueror; delete
any files/directories you don't want and then copy any
new ones across; unmount the USB; and, unplug it.
FAT - Thin on names
One thing to be aware of is that USB MP3 players are
effectively flash disks and as such, use 'vfat' (FAT) as
the file system (so that they will work with Windows
machines). The only problem you are likely to encounter
with this is if you use camel notation for otherwise
identical file names so 'NotHere' and 'NoThere' are the
same under vfat.
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CPAN - Perl modules
One problem that you might find is that, if you have
only the very basic installation of Perl, you might not
have the Perl modules installed on your system that you
need in order to use ogg2mp3, namely: File; Getopt; and
String. If you cannot find these on your system
installation discs, you can find them at CPAN (on SuSE
Linux 8.2, the only one you will need to download is
String) which is at www.cpan.org or you can find the RPMs
at the RPM Repository (http://rpmfind.net/linux/RPM/CPAN_String.html
to download the 'String-ShellQuote module').
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Future-proofing
The question still remains about which MP3 player to
get. Size is one issue but there is also one about the
types of files it can read. First of all, size.
For an eight hour
shift, you will need around 400MB of space (remember that
you will only be working for 7.5 hours) and also, you
have the luxury of being able to delete and copy any
selection you like so changing the songs that you listen
to will be a lot easier. The drives that are available
tend to go up in multiples of two so a 512MB MP3 player
will have plenty of space.
If you are planning to get a 1GB or even a 2GB MP3
player, one thing that goes in its favour is that when
you turn them back on again, they remember where you left
off, so you are not left scrolling through hundreds of
tracks, trying to find one that you have not listened to
recently. One word of warning though is that when the
battery runs out (this is one of those technologies where
it has all become so small that even the single AAA sized
battery weighs almost as much as the rest of it) it only
remembers where it was when it was last switched off
which could be as much as six hours ago.
File types are another matter. Each time a music
vendor sells an .mp3 track, they are responsible for
paying Fraunhofer a percentage of each sale for using
their patents. Ogg Vorbis is patent and license-free and
as the quality for a given file size/bit rate is
demonstrably better, it is only natural for music vendors
to move over to .ogg given time. Therefore, you are
really better off getting an MP3 player that can have its
firmware updated so that it includes Ogg Vorbis codecs.
Apart from better quality with Ogg Vorbis, you will be
able to get more music on there and if you buy music
online, there is the potential for the savings in
licensing to be passed on to the purchaser although with
this latter point, I wouldn't hold your breath waiting.
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