Thursday, August 19, 2010

Standalone DVD recorders

When the standalone DVD recorder first appeared on the Japanese consumer market in 1999, these early units were very expensive, costing between $2500 and $4000 USD. However, as of early 2007, DVD recorders from notable brands are selling for US$200 or €150 and less, with even lower "street prices". Early units supported only DVD-RAM and DVD-R discs, but the more recent units can record to all major formatsDVD-R, DVD-RW, DVD+R, DVD+RW, DVD-R DL and DVD+R DL. Some models now include mechanical hard disk drive-based digital video recorders (DVRs) to improve ease of use. Standalone DVD recorders generally have basic DVD authoring software built in; however, the appearance of the finished DVD is very basic and usually completely under the control of the unit.

Some believed that DVD recorders would supersede the VCR as the standard television-recording device; however as technology progresses, in 2009 Panasonic introduced the world's first Blu-ray disc recorder which is capable of recording both DVDs and Blu-ray discs and features built in satellite HDTV tuners. A year later, Panasonic introduced further more Blu-ray disc recorders with terrestrial HDTV tuners.

DVD recorders have several technical advantages over VCRs, including:

  • Superior video and audio quality
  • Easy-to-handle smaller form-factor disc media, and more durable than magnetic tape.
  • Random access to video chapters without rewinding or fast-forwarding (serial access)
  • Onscreen multilingual subtitles and labeling not available on VCRs
  • Reduced playback wear and tear
  • High-quality digital copying, with little or no generation loss
  • Improved editing, at least on rewritable media
  • Playlisting
  • No risk of accidentally recording over existing content or unexpectedly running out of space during recording
  • Easy to find recordings due to chapter menus

Note: in addition Blu-ray disc recorders can record full high definition videos on BD-Rs and BD-REs.

It does have some disadvantages

  • Slow initial access/load times due to the optical nature of the disc
  • Limited rewritability on DVDRW(+RW) discs (typically around 1000). DVD-RAM is better suited for high frequency re-recording (around 100,000 rewrites)
  • Relatively short life of the laser diodes (average of about 2 years depending on usage).

However, an inconvenience exists in which DVDs recorded with DVD recorders must be finalized to view in other DVD players. (This disadvantage does not apply to DVD-RAM or DVD+RW discs, which require no finalization due to their 'random access' nature.) Also, the implementation of MPEG-2 compression used on most standalone DVD recorders is required to compress the picture data in real time, producing results that may not be up to the standard of professionally rendered DVD video, which can take days to compress.

The United States is converting its over-the-air television broadcasts to digital "ATSC" in June 2009, however this will have very limited impact in ending the need for DVD recorders to perform realtime MPEG-2 encoding or transcoding. The only setup where ATSC could conceivably eliminate MPEG-2 encoding/transcoding in a DVD recorder would be where an antenna is hooked directly into a DVD recorder that has an integrated ATSC tuner. Even then however, the DVD recorder will have to transcode the ATSC MPEG-2 into DVD-Video-legal MPEG-2 if the ATSC MPEG-2 stream isn't already DVD-Video-compatible. This would require transcoding for all high-definition broadcasts and some if not all standard-definition broadcasts. The same general situation applies to digital cable service; only DVD recorders with integrated digital cable ("QAM") tuners can possibly avoid transcoding, and then only if the digital cable system is already sending a DVD-Video-compatible MPEG-2 stream, which again requires transcoding of all HD content and some if not all SD content. All other setups (digital cable box's analog outputs to DVD recorder, satellite box's analog outputs to DVD recorder, DVD recorder tuning and recording analog cable channels which are still permitted after 2/2009, etc.) usually always involve an analog step with MPEG-2 encoding being necessary inside the DVD recorder.

A number of manufacturers have combined DVD recorders with mechanical hard disk drive-based digital video recorders, allowing for recording to large fixed disks, and the ability to view these recordings off the hard disk at a later date.

In Japan, AVCREC recorders, which are able to record MPEG-2 or AVC high definition video from ISDB broadcast with or without re-encoding, get increasingly popular. Initially, AVCREC recorders use DVD recordable discs, but newer models are able to record onto Blu-ray discs as well onto hard disk drives.

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