DVD Recording Questions
We get a lot of phone calls about DVD-R because it is a new technology and has been in the news a lot. Here are a few of the most common questions:
1. Can I copy entertainment titles on DVD? Someone said there's software out there to get around the encryption.
No. Most DVDs are copy protected in one way or another, mainly by CSS encryption or MacroVision. Even if you could get around this, a pressed DVD can hold up to around 20 GB of data and video. Your DVD-R only holds 4.7 GB, and you have to re-author the video anyway. Do the industry a favor and pay for your titles; if you like it enough to own it, show your appreciatilon to the people who put their time and effort into creating it.
2. What is DVD-RAM? Can I use it like a regular DVD?
DVD-RAM is almost entirely unrelated to DVD and DVD-R. It is a sectored media (like a hard drive) and is designed for write-multiple usage. It is not playable in most consumer DVD players. Its purpose is not usually video-type application.
3. What is the difference between "Authoring" and "General Purpose" media?
The original Pioneer DVD recorders used authoring media; this can be given to a plant to be used as a master for replication.
DVD recording became mainstream when a less expensive DVD recorder was introduced by Pioneer for general use. It uses a 650 nm laser, just like a CD recorder, so it is less expensive to manufacture. The authoring recorders used a 635 nm laser.
You can't put authoring media in a general purpose drive. And if you send a general purpose disc to a replication plant, it will have to be transferred to DLT tape before it can be replicated.
4. What about HD DVD?
HD-DVD (HD stands for both High Definition and High Density) formats use smaller wavelength (405 nm) blue or violet lasers, where DVD uses longer (650 nm) red lasers, which make it possible to focus the laser with great precision. This allws data to be more tightly packed and stored in less space on the same size disc.
At the current time there are five HD-DVD "up-and-comers", with the possibilty of more on the way. The following is a summary of these five:
Format | Data Depth | Laser | Video | Audio | Capacity (single/dual layer) | Data rate |
WMV HD | 0.6 mm | Red (650 nm) | WMV9 | WMA9 | 4.7 GB / 8.5 GB (standard DVD) | 22 Mbps |
HD-DVD | 0.6 mm | Blue (405 nm) | MPEG-2 SD/HD, H.264, VC-1 | PCM, MLP, Dolby Digital +, DTS HD | 15 GB / 30 GB (ROM), 20 GB / 40 GB (Recordable) | 36 Mbps |
Blu-ray (BD) | 0.1 mm | Blue (405 nm) | MPEG-2 HD, H.264, VC-1 | PCM, Doby Digital, DTS | 27 GB / 50 GB | 36 Mbps |
EVD | 0.6 mm | Red (650 nm) | HD MPEG-2 | ExAC | na / 8.5 GB (ROM) | 22 Mbps |
FVD | 0.6 mm | Red (650 nm) | WMV9 (1280x720) | WMA9 | 6 GB / 11 GB | 25.05 Mbps |
HD discs will not play on existing DVD players, even red laser discs, because players requre new circuitry to decode and display the HD video and blue-laser discs requre new optical assemblies and controllers.