The benefits of Blu-ray vs. DVD
For a while now, DVDs have been the standard format for optical media, as it holds much more data than CD-R and is more versatile by allowing the user to store data such as images and photos, but also create playable Movies and audio discs from DVDs. By now, most people in the country have a DVD player, or have access to one in their home.
The newest of optical media is called the Blu-ray disc. These discs were designed to supersede the DVD format by providing larger storage capacity and versatility than existing DVDs. Blu-ray discs are called such because instead of a red laser which is used to read DVDs, Blu-ray uses a shorter, more precise wavelength laser which is called “Blue” but is actually more violet colored. This finer laser allows for much more precise data reading when compared to the larger red lasers found in CD-R and DVD-R readers.
More and more people are getting the equipment necessary to view and enjoy Blu-ray discs and even have begun to transfer their memories such as video to Blu-ray, film to Blu-ray and high definition slideshows.
Storage Capacity
The main benefit of Blu-ray over DVDs is the increased storage capacity. This feature helps propel Blu-ray ahead of the competition because typically, higher storage capacity translates to higher video resolution and audio quality on your TV screen. The Blu-ray format offers as much as 5X the storage capacity of traditional DVDs, it can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc.
[blu-ray]
| Type of Disc | Diameter (cm) | Layers | Capacity (Bytes) | Capacity (GB) |
|---|---|---|---|---|
| Blu-ray Single Layer | 12 | 1 | 25,025,314,816 | 25.0 |
| Blu-ray Dual Layer | 12 | 2 | 50,050,629,632 | 50.1 |
| Mini Blu-ray Single Layer | 8 | 1 | 7,791,181,824 | 7.8 |
| Mini Blu-ray Double Layer | 8 | 2 | 15,582,363,648 | 15.6 |
[dvd]
| Type of Disc | Diameter (cm) | Layers | Capacity (GB) |
|---|---|---|---|
| DVD Single Layer | 12 | 1 | 4.7 |
| DVD Dual Layer | 12 | 2 | 8.5 |
| Mini DVD Single Layer | 8 | 1 | 2.66 |
| Mini DVD Double Layer | 8 | 2 | 5.2 |
Video Quality
Because of the enhanced storage capacity, higher resolution video is able to be placed onto Blu-ray discs with resolutions up to 1080p. This superior resolution is what really make Blu-ray video stand out from DVDs. A higher resolution image means the viewer sees more, sharper detail when they watch the screen. Blu-rays maximum resolution is 1080p, which is a far cry from DVDs 480p maximum. This is the main reason that Blu-rays look so much better than DVDs at a glance.
| Parameters | Blu-ray | DVD |
|---|---|---|
| Video resolution (max) Video bit rate (max) |
1920×1080 (1080p) 40.0Mbps |
720×480/720×576 (480i/576i) 9.8Mbps |
| Video codecs | MPEG-2 MPEG-4 AVC SMPTE VC-1 |
MPEG-2 – – |
Audio Quality
More storage capacity also means higher quality audio can be placed onto the disc. Blu-ray movies can come with high resolution soundtracks like Dolby TrueHD and DTS-HD Master Audio so you’ll be hearing things exactly how the filmmakers intended. Audio no longer needs to be compressed in order to fit onto the disc like it was with DVD movies.
| Parameters | Blu-ray | DVD |
|---|---|---|
| Audio codecs | Linear PCM Dolby Digital Dolby Digital Plus Dolby TrueHD DTS Digital Surround DTS-HD |
Linear PCM Dolby Digital DTS Surround Sound – – – |