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BOOT CAMP 252 (19/11/02)
MAKING YOUR OWN CDS & DVDS,
part 2
Last week, in part one of the Boot Camp guide to CD and DVD
recording we managed to avoid using too much jargon, sadly when it comes to the
nitty-gritty of actually making discs you will need to familiarise yourself with
a few basic terms. This week we’ll also be looking at CD-writer software, but
first a short lesson in DIY CD technospeak.
There are basically three ways of recording data on a
recordable or rewritable (CD-R/CD-RW) disc and that’s ‘Disc At Once’ (DAO),
‘Track At Once’ (TAO) and ‘Packet Writing’.
Disc At Once means the disc is recorded in one session, it’s
mainly used for copying or making backups of discs and it’s a way of ensuring
maximum compatibility with other CD devices. However, it’s vitally important
that there are no interruptions whilst the disc is being recorded or ‘burned’.
Any gaps or pauses, however brief, will render the disc unreadable, so it’s a
good idea to exit all programs, disconnect form the Internet and generally leave
the PC alone whilst a disc is being recorded.
Track At Once recording is used for ‘multi-session’
recording, such as making an audio CD compilation of tracks from several albums.
It’s also handy for backing up files and folders on your PC over a period of
time. TAO recording is very flexible and the disc can be read by the CD-Writer
on which it is being made but it has to be ‘closed’ or ‘finalised’ before it can
be read on another PC or a CD player.
Packet writing is a variant of TAO recording, and overcomes
problems with the way data has to be organised into uniform blocks or tracks in
TAO recording. Packet writing allows files of any size to be recorded onto the
disc, making more efficient use of the space available and it allows data on
rewritable (CD-RW) discs to be selectively erased, effectively turning a CD-R/RW
into a giant 650Mb floppy disc. The downside is reduced compatibility, it is
less reliable -- if a writing session fails all of the previously recorded data
on the disc may be lost -- and the relevant software used to format the disc has
to be running on the PC in order to read and write data.
In addition to the three main recording methods there are
various ways of organising or formatting the data on the disc. In practice you
only really need to be aware of three of them, known as ISO 9660, Joliet and UDF
ISO 9660 is the original data-recording format for CD-ROMs,
it’s an international standard, recognised by all CD and CD-ROM drives, software
and operating systems. All fine and dandy, the only trouble is it was created
back in 1988 and has one serious limitation; it cannot handle long file names.
The names of files in the original DOS and early Windows filing systems are
limited in length to eight characters plus a three-character extension,
separated by a full stop (known as the ‘8.3’ format). Support for long file
names was introduced with Windows 95 but the original ISO 9660 filing system
couldn’t cope, so additional ‘levels’ were developed that would recognise files
names up to 255 characters in length.
Meanwhile, Microsoft set about developing its own long file
name modification for the ISO 9660 format, called Joliet. This allows for
filenames up to 64 characters (including spaces).
UDF or the Universal Disc Format (also known as ISO/IEC 13346) is the most
recent development in recordable CD filing systems and should eventually replace
the ageing ISO and Joliet formats. It is used when recording CD-R/RW discs in
packet writing mode and is the standard filing system for DVD data recording.
Normally you won’t need to worry about which filing system to
use, most CD-writer software is configured automatically according to the disc
and type of recording you are making. The only time it is likely to be an issue
is if you try to copy a file with a filename longer than 64 characters, in which
case you may be prompted to rename it, skip it or change to a different
recording method.
One other term you may come across, particularly if you are
shopping around for a CD-writer or PC with a built-in writer is ‘Burn-proof’.
This slightly unfortunate turn of phrase is often confused with ‘burning’ the
jargon term for recording a CD on a PC. ‘Burn’ is actually a contraction of
‘Buffer-Underrun’, which happens when the PC can’t supply data quickly enough to
the CD-writer. To overcome this most recent CD-writers have a memory module that
acts as a ‘buffer’, to ensure a steady flow of data onto the disc. If the buffer
runs out of data, because the PC’s hard disc drive is busy with another task the
buffer underrun will occur and the recording will be ruined. As a general rule
of thumb the larger the buffer memory a CD-writer has the less chance there is
of it happening.
CD-WRITER SOFTWARE
Almost all CD writers come with a suite of software and in
most cases this will be Roxio’s Easy CD Creator, some packages may also include
Roxio’s Direct CD, for UDF packet writing (www.roxio.com). Between them these programs do
most things very well and if you’re new to CD writing it’s worth sticking with
them.
Roxio’s main rival is Nero, from Ahead Software (www.ahead.de/en/index.html#root).
Nero Burning is also bundled with a lot of CD writers and again it’s a well
thought out package, with a packet writing utility in later versions; it’s easy
to use and generally very reliable.
There are also lots of specialist programs on the market, for
copying or ‘cloning’ CDs, making audio and MP3 compilations. You’ll find a most
of them listed at: (http://www.cdmediaworld.com/hardware/
cdrom/cd_cd-writer_software.shtml).
Incidentally, Windows XP has CD writer support built in, using a customised
version of Roxio’s Easy CD Creator.
Next week – Making backups
JARGON FILTER
FINALISING
Also known as ‘closing’ – process of recording a CD’s table
of contents or TOC, which will allow it to be read (or played) on any PC or CD
audio player.
ISO
International standards organisation – body responsible for
creating technical standards, recognised by more than 140 countries
SESSION
Adding data to a recordable CD, prior to the disc being
closed or finalised
TOP TIP
If you are using Windows 95 (OSR2) or Windows 98 onwards with
a CD writer you should change your computer ‘type’ from Desktop PC to Network
Server. This will increase the size of the file system cache memory, which can
help to prevent buffer underruns when recording in Disc At Once mode. To make
the change right click on My Computer, select Properties, to open System
Properties, select the Performance Tab then File System and make the change on
the ‘Typical Role…’ drop down menu.
NEXT
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