Hi,
One by one you all have helped me resolve my problems. Thanks. Here's one
that is puzzling me. When we first opened the box with the new computer
tower in it, I noticed this yellow sheet with bold print on it saying "READ
ME FIRST When creating audio, data, or backup discs, verify the disc after
recording to optical media to confirm the data was written successfully."
My question is this ... how do I verify that the data was written
successfully?
Nancy
Really long answer... <wink>
It depends on the data. If you are just backing up files, like a
spreadsheet or your secret recipe for Angel Food cake a simple verify
is all you need and there is lots of software that can do it
automatically. Nero probably has a option for many tasks, since I'm
using Easy Creator I KNOW it does. It does tend to slow down the
process. If you always want to write and verify, the data you burned
gets read back and compared byte by bytes to see if you got an exact
duplicate, depends on the importance of the data.
Now the bad news. Burning both audio and video files is different.
Unlike the commerical process where copies are made from a "master
copy" and actually the data is embedded on the disc under pressure,
similar to how dollar bills are printed from a master engraved master
under high pressure when you do home brew DVD creation the process is
very different and many errors can creep in. Therefore if this kind of
data is important to you the only way to verify is play it back and
watch every minute of it if its a video.
Here's why:
1. Bad media. The blank discs you buy may have flaws. You rarely can
see them, but the laser trying to read them sure can and just a
very slight imperfection may cause the laser to bounce the light
ever so slightly off track and you'll get a glitch meaning the DVD
will stutter, stall, show artifacts, breakup, distort the audio or
simply refuse to play at all or just stop at some point.
Sorry, no cure. Just a fact of life. For every 100 disc stack of
blank media you buy expect one or two to be bad. Sometimes way
more.
2. It could be your DVD burner. As a DVD gets encoded tiny errors
should be compensated for, this is build into the firmware. Again,
sometimes this exceeds tolerances and while your DVD burner may
say it encountered a error during the burning process and just
stop and then spit out the DVD that now is just a coaster, errors
non the less can happen and there's no way of knowing unless you
play the disc all the way through.
3. It could be your DVD player. Especially true for set top boxes
you attach to your TV to play DVDs through your televison. Again
the tolerance can be such Brand A may not be able to handle media
that Brand B can, or be less sensentive to flaws. A bigger issues
is people use the wrong bitrate to encode their DVD to. Most people
think more is better and will use the highest bitrate the
application supports. While there are standards, the sad fact is
many DVD players can't handle bitrates in the high end of the
tolerance range and can show all the symptoms of a bad burn I
mentioned earlier.
4. Could be the brand. Not all blank media is created equal. Some
simply refuse to be read in some DVD players, yet they will
play fine in another, often play fine in your computer. This is
typically due to differences in the reflectivity of the coating.
Which brings me to my last warning. If you burn DVD's and plan to
view them on a big screen TV in the den, don't test them on
your computer and assume if they play fine there they will
play fine on your big screen. Test on the device you plan to
watch the finished DVD on, otherwise you may be sorry and no
longer have the source files to try again.
So to be sure, if what your burning is important to you and we're
talking audio or video, the only way to be sure is play it all the way
through and verify that way it is a good copy.
