HD DVD
HD DVD (short for High Density Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format, but lost to Blu-ray, supported by Sony and others.
Reverse side of an HD DVD | |
| Media type | High-density optical disc |
|---|---|
| Encoding | VC-1, H.264, and MPEG-2 |
| Capacity | 15 GB (single layer) 30 GB (dual layer) |
| Read mechanism | 405 nm laser: 1× @ 36 Mbit/s & 2× @ 72 Mbit/s |
| Write mechanism | 405 nm laser: 1× @ 36 Mbit/s & 2× @ 72 Mbit/s |
| Developed by | |
| Usage | Data storage, 1080p high-definition video |
| Extended from | DVD, DVD-Video |
| Extended to | Blu-ray Disc |
| Released | March 31, 2006 |
| Discontinued | March 28, 2008 (1 year, 11 months and 28 days) |
| Optical discs |
|---|
HD DVD employed a blue laser with a shorter wavelength (with the exception of the 3× DVD and HD REC variants), and it stored about 3.2 times as much data per layer as its predecessor (maximum capacity: 15 GB per layer compared to 4.7 GB per layer on a DVD). The format was commercially released in 2006 and fought a protracted format war with rival Blu-ray. On February 19, 2008, Toshiba abandoned the format, announcing it would no longer manufacture HD DVD players and drives. The HD DVD Promotion Group was dissolved on March 28, 2008.
The HD DVD physical disc specifications (but not the codecs) were used as the basis for the China Blue High-definition Disc (CBHD) formerly called CH-DVD.