Now that the MacWorld
dust has settled a little (partially helped by all that San Francisco
rain), several questions came up regarding Apple's upcoming DVD recording
capabilities. Let's go over the most common ones:
you purchase the new 733MHz G4 in order to get a SuperDrive?
Not really! As you
can read in my "The
DVD Revolution is for Everyone" story, the SuperDrive is nothing
but Pioneer's brand new DVR-A03 DVD-R drive, which will be available
for sale to the general public around April or May for a MSRP of $995.
The question remains regarding the availablity of the iDVD software.
Although it was announced by Apple that this is a free program, for
the time being it will only ship with the SuperDrive-equipped G4s. No
word yet if you will be able to purchase this software separately or
if it will, like iTunes, be posted on Apple's site for download.
it true that iDVD imposes a one-hour video limit?
Yes, it is. There
has been some speculation that this limit was caused by the SuperDrive.
Others were wondering whether Apple imposed this limit on the iDVD software
to sell its $995 DVD Studio Pro professional DVD authoring program.
It is clear that this is not the SuperDrive's (or Pioneer DVR-A03's)
fault, as the unit is capable of burning 4.6GB of data on a single-layer
disk. Using variable bit rate (VBR) compression, this translates into
over two hours of high-quality video. As an example, a fixed 4Mb/s rate
on 4GB media will give you two hours and sixteen minutes.
It seems that the reason for the one-hour limit is that iDVD encodes
at a set rate of 8Mb/s. This high data rate ensures that the video will
be of high quality, which is an important consideration because iDVD
is supposed to be a consumer/prosumer application. And since most post-production
facilities will likely be burning sub one-hour DVDs, the speed and ease
of use should be more important than storage efficency. DVD Studio Pro
lifts this limitation, by the way, enabling you to chose your encoding
rate. It also supports more efficient, high quality audio compression
formats (iDVD apparently only encodes using PCM), including 5.1 Dolby
the 2x encoding speed announced by Apple available all the time?
Probably not, unless you are using iDVD with its fixed
8Mb/s rate. This constant level of compression is a lot less taxing
on the system than good looking higher compression, specially VBR.
With VBR the software must analyze virtualy every frame
in order to minimize the artifacts.
If a particular shot requires less compression, the software will figure
it out, just as it determines which parts can accommodate a lot of compression.
This is why most software-based compressors turn out better quality
than most hardware-based compressors. You trade speed for quality.
What is nice about
the iDVD setup is the optimization that went into it, enabling you to
obtain very high quality, very quickly. If you need more than one hour
on a DVD, then just let the machine work overnight.
SuperDrive burn dual-layer DVDs?
No. And this is neither
Apple's or Pioneer's fault. To this date no DVD recorders are capable
of burning dual-layer DVDs. You can author dual-layer DVD-9 DVDs in
DVD Studio Pro, though, and as long as you save the data to the right
tape format (DLT), you can have the DVDs pressed by a service bureau.
This is not an inexpensive proposition, though, as a master must be
made an a minimum number of copies pressed.
For more information,
please check our "Apple
SuperDrive and iDVD. The DVD authoring revolution has arrived"
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