DVD-R, like the CD-R, offers write-once recording and has a capacity of 4.7GB per side. DVD-R discs make use of a similar technology to CD-Rs but with a different dye and smaller geometries. The first version of this format had a capacity of 3.95GB but this has been increased to 4.7GB per side.
There are two types of DVD-R disc ver 2.0 both with a capacity of 4.7GB.
- General purpose discs are intended for use by consumers but do not allow any data to be written to the lead-in area. This means that, for example, CSS copy protection cannot be used, but provision is made for adding CPRM copy protection.
- Authoring use discs which are intended to be used by authoring studios to test titles and also as media for glass mastering.
The two different types require two different recorders and media. One recorder can only write one type of media.
Parameter | Ver 1.0 | Authoring use | General use |
Number of Sides | 1 or 2 | 1 or 2 | |
Capacity (GB) | 3.95 | 4.7 | 4.7 |
Recording method | Organic dye layer | ||
Laser wavelength | 635/650nm | 635nm | 650nm |
Min pit length (microns) | 0.44 | 0.40 | 0.40 |
Track pitch (microns) | 0.80 | 0.74 | 0.74 |
Laser wavelength | 635/650nm | 635nm | 650nm |
Pre-pit addressing | increment | increment | decrement |
Serialisation for CPRM | No | Yes | |
Pre-recording | No | Yes | |
Track format | Wobble pre-groove | ||
Modulation & error correction | 8 to 16 & RSPC |
DVD-R is compatible with DVD-ROM, DVD-Video and DVD-Audio so that recorded DVD-R discs can be read on any suitable DVD hardware, depending on the format of the data contained on the DVD-R. However discs cannot use CSS copy protection. Also DVD-9 discs cannot be written to DVD-R.
DVD-R discs comprise the following data areas:
- Power Calibration Area (PCA)
- Recording Management Area (RMA)
- Lead-in Area
- Data Recordable Area
- Lead-out Area
DVD-R discs allow incremental writing (cf CD-R multisession writing). Two types of incremental writing are defined:
- Type 1 allows DVD-R discs to be read by an ISO 9660 system, and uses the UDF Bridge file system.
- Type 2 is for drag and drop file transfer and uses UDF without ISO 9660.
For both types each section of data written to the disc is a Bordered Area and is followed by the Border Out and Border In which precedes the next Bordered Area (if any). Each Bordered Area begins with the UDF file system and ends with the Virtual Allocation Table (VAT).
DVD-R discs and recorders are available and prices have been dropping to consumer price levels. Combination drives are now available which write CD-R, CD-RW, DVD-R, DVD-RW, DVD-DL, DVD+R, DVD+RW and DVD+DL discs.