Blu-ray Disc is the successor to the DVD format for high-definition (HD) entertainment. It offers 5 times the picture quality of DVD and advanced interactivity. It enables recording,
rewriting and playback of high-definition content, and storing large amounts of data. Blu-ray is
currently supported by the world's leading consumer electronics,
personal computer, recording media, video games, and music companies.
The format is also supported by all Hollywood studios and countless smaller studios.
Co-developed by Sony, Philips, and Pioneer, Blu-ray Disc takes its name from the blue laser
pickup which reads the digital data stored on the disc. Because the blue laser has a shorter
wavelength, data can be stored more densely on a Blu-ray than on a DVD.
Here are the 6 key differences between Blu-ray and DVD:
- Storage Capacity - The main benefit of Blu-ray Discs over DVDs is
the increased storage capacity. The Blu-ray format offers as much as 5 times the
storage capacity of traditional DVDs. It can hold up to 25GB on a single-layer disc
and 50GB on a dual-layer disc. This increased storage capacity translates to higher
video resolution and audio quality on your TV screen. Because Blu-ray Discs can store
25GB of data, you can fit an entire HD movie on a single layer disc.
- Picture Quality - The DVD format is limited to a resolution
of 720 x 480 pixels, which is called SD (Standard Definition). This resolution looks fine
on a standard old "tube” TV, utilizing all available pixels on the screen. However,
if blown up to accommodate a widescreen HDTV, the picture needs to be up-converted
and looks grainy.
Blu-ray resolution can be as high as 1920 x 1080 pixels, which is called Full HD (High Definition). This superior resolution is
what really makes Blu-ray stand out from DVD. A higher-resolution image means
the viewers see sharper and clearer images on the screen.
Furthermore, Blu-ray uses a progressive scan format that projects the entire image in each frame. By contrast, DVD
uses an interlaced format, where individual frames project alternating lines of video.
Progressive scan images are clearer and sharper than interlaced images.
- Audio Quality - Both Blu-ray and DVD can store uncompressed audio. However,
Blu-ray's extensive storage capabilities allow it to store more channels of audio than DVD.
To compensate for the lack of storage, most DVDs on the market today use
compressed audio, which results in lower quality audio reproduction. This is critical
especially for the music market, which strives to deliver the best audio quality.
- Bonus Features - The added space that gives Blu-ray better picture
quality and better audio quality also gives the medium added space for lots of bonus
features. More commentary tracks, deleted scenes, and behind-the-scenes footage
are possible with the extra space. Unlike DVD players, Blu-ray players can be connected
to the Internet, as well, allowing for Internet-enhanced content.
- Cost - Blu-ray Disc players on the market today sell for as low as $60, and also support DVD playback.
- Menus - Blu-ray offers better interactivity than DVD – specifically,
with menus that can run concurrently with the film. For example, while watching
the movie, the viewer can launch a pop-up menu on the screen and access any part of the movie without having to stop playback. This pop-up menu feature is not available
on DVD, which requires the viewer to stop playback and access the menu, interrupting the movie.