Hardware Reference
In-Depth Information
tions for higher-capacity optical storage is recording high-definition TV, which takes an
incredible amount of storage. Current DVD recorders can't store enough data to handle
high-definition video. Blu-ray, on the other hand, is designed to store up to 4.5 hours
of high-definition video (or more than 13 hours of standard broadcast-quality TV) on a
single-layer disc, and 9 hours on dual-layer versions. As with DVD, Blu-ray uses the
industry-standard MPEG-2 compression technology.
Figure 11.15
compares the track size and laser types used for CD, DVD, and standard BD
media.
Figure 11.15
CD, DVD, and BD media and laser comparison.
Note
When a mixture of HD video and standard video is stored on a BD, you can store up to 2.25
hours of HD video and 2 hours of standard video (used for bonus features) on a single-layer
disc. A dual-layer BD can store up to 3 hours of HD video and 9 hours of standard video.
Capacities can also vary with bit rates used for movie storage because Blu-ray can support a
range of bit rates.
The BD specification includes the following formats:
•
BD-ROM
—Read-only for prerecorded content
•
BD-R
—Recordable
•
BD-RE
—Rewritable
