Although, DVD renders standard video with better colour and detail, neither does it have the capacity to store so large information as required for recording high definition video nor does it work well with HDTVs. Standard DVD produces excellent results when it outputs video on a screen size less than 40″. However, on larger screens, DVD picture had the tendency to show more scan lines thus affecting the over-all picture quality.
True high definition recording and playback needed a new format that can successfully handle these problems. As a result, two high definition formats were introduced in home entertainment market – HD DVD and blu-ray. They are competing technologies and have been trying to succeed DVD as the future video format.
There are both similarities and differences between DVD and HD-DVD. Both formats use the optical disc of same size(12 cm diameter). They were developed on the common principles of high density storage using laser technology. DVDs come with double layered and double sided capacities. So do HD-DVDs. So, what are the differences between HD-DVD and DVD lie and what are the additional features of HD DVD that make it a high definition format?
Comparing availability of HD DVD and DVD
Currently, DVD enjoys the support of all Hollywood studios and has the largest number of movie titles to its credit. There are more than 50,000 movie titles available in DVD format by the end of 2007.
HD-DVD version of movies are available in the home video market but the number is dwindling as many studios had switched to its rival format, blu-ray. There were around 340 movie titles HD-DVD format by the end of 2007.
HD-DVD players have backward compatibility with DVD. This means you can still use your DVD library on HD DVD player. HD-DVD players are available with high end models adding newer features. They are also much cheaper when compared with blu-ray players costing just one-third of the price of blu-ray player.
Storage Capacity
HD-DVD can hold more than three times as much information as DVD. Double layer, double side discs are available in both formats.
| Storage capacity | DVD | HD-DVD |
|---|---|---|
| Single layer | 4.7GB | 15GB |
| Double layer | 8.5GB | 30GB |
Video Resolution
Standard DVD supports EDTV resolution of 720×480 pixels either in interlaced scan or progressive scan format. However, the HDTV can support both lower resolutions like SDTV, EDTV as well as higher resolutions of HDTV(720p, 1080i and 1080p).
Some DVD players use upscaling method where HDMI connections are used to enhance the video quality of standard DVD, however, the results are much better only on HDTV enabled TV sets.
Video Compression methods
Standard DVD uses MPEG-2 to encode the information on the disc. While this technology lacks compression capabilities to encode high definition contents, HD-DVD need to use more efficient video codecs like MPEG-4, VC-1 or AVC. VC-1 is so far the best compression method and most movie titles in HD-DVD version have used this codec.
HD-DVD is also compatible with MPEG-2 thus making DVD playable on a HD DVD player.
Audio standards
Both HD-DVD and DVD support digital sound surround features. Standard DVD supports both DTS and Dolby sound systems, but still audio experience lacks in fidelity when compared with HD-DVD.
Sound tracks in HD-DVD are encoded in higher bandwidth (24 bit/192Khz) and support a variety of sound tracks that include Dolby TrueHD, Dolby Digital Plus, DTS-HD, DTS, Dolby Digital etc. There are as many as eight sound channels that can be encoded on HD-DVD. This is how HD-DVD movies are able to provide amazing audio experience in a hometheater setup.
Data transfer speed
HD-DVD players come with high speed drives that can transfer information at a rate of 36 Mbits/s. This speed is ideal, when it comes to recording or playback of high definition contents. This speed is also nearly three times faster than a standard DVD player.
There is also 2X drive that has twice this speed (72 Mbits/s) and can write on a double layered HD-DVD disc in less than an hour.
Input and Output connections
Typically, standard DVD player comes with connection options like S-video, composite and component video outputs and analog stereo, digital coaxial and digital optical audio connections.
HD DVD players do have the same connections plus HDMI output to send high definition contents to HDTV. To use HD DVD player with your existing TV, it should have composite video input as a minimum requirement. However, if you want to play high definition video, your TV should be enabled with either component or HDMI connection.
Region coding
DVDs and DVD players come with region coding while HD DVDs do not. However, this is about to change, as HD DVDs and players will come with region coding in near future. This means, you will have to buy movie titles with region code according to your geographical location.
Price factor
Currently, the price factor is in favour of DVD players and DVDs. Ever since DVD first hit the market in 1997, the prices have been falling making it so competitive in home video market.
HD-DVDs are still expensive and need a few more years for the prices to come down. HD-DVD player cost almost double the price of a standard DVD player while HD-DVD version of a movie title cost as much four times as DVD movie.
However, there is a big advantage with HD-DVD player, as DVD is still playable on it. Along with it, you can also play high definition videos.
Related posts: