User talk:Kerstin

HD vs. Blue-ray movies

“Warner Brothers has declared for Sony's Blue Ray, hot on the heels of Toshiba winning Microsoft and Intel support, which pledges technical and marketing expertise for the HD DVD format. Both are crucial players in the stand-off, and as customers increasingly use computers to play DVDs, both had previously refrained from taking sides as they sell software and components to Sony and Toshiba.

Supporters of the Blu-Ray technology include Apple, Dell, HP and Samsung Electronics. Among the Hollywood studios, are Walt Disney and Sony Pictures Entertainment, joined now by Warner Brothers.

Hollywood studios could ultimately decide the fate of the formats. These are split in support for Toshiba or Sony, with Warner Bros now announcing that it will launch video content for the Blu-Ray format. HD DVD supporters can only offer NBC Universal. Sony's Blu-Ray disc expects to have a greater storage capacity than the HD DVD, but to be more expensive to make, at least in the short term, as the format has the greater differences from current generation DVDs.”

Summary: During the “war” to see which high definition DVD format would be used, Warner Brothers, Apple, Dell, HP, and Samsung Electronics supported the use of Blu-ray, made by Sony, while Microsoft and Intel support supported HD DVD format, made by Toshiba (Unknown 2005).

Unknown Author (2005) Paramount Backs Sony in HD-DVD Recorder Format Wars. III-Vs Review, Vol. 18 No. 8: pp. 4.

“Blu-ray and HD DVD produce equally sharp images. The quality of imagers as compared with that produced by standard DVD is not as dramatic as the improvement DVD provides over video-tape, however, and some wags wonder if such a modest gain is worth the cost of players and disks. Undaunted, the two camps are now trying to distinguish themselves in a capacity race. An HD DVD disk holds 15 gigabytes of data, and a Blu-ray disk holds 25 gigabytes. Because most HD DVDs use the MPEG-4 data-compression scheme rather than the MPEG-2 scheme still used by most Blu-ray disks, however, both are sufficient to store full-length movies plus some extra features. Makers have also begun offering so-called dual-layer disks that double those capacities on a single side. Although the hike allows even more extras and advanced audio to be added, "there is a little bit of 'mine is bigger than yours,'" notes Steve Wyatt, global marketing director for media at GE Plastics in the Netherlands. Some makers have even prototyped triple-layer disks. Combination players and two-sided disks suggest both formats could coexist. "But if manufacturers want to keep it simple for the consumer and for retailers," Wyatt proposes, "one formal is better than two." CD    DVD     HD DVD    Blu-ray

Single-layer disk capacity (GB)   0.7     4.7       15         25 Laser wavelength (nm)             780     650      405        405 Minimum pit length (μm)           0.8     0.4      0.2       0.15 Track pitch (μm)                  1.6    0.74      0.4       0.32

DIAGRAM: COMBINATION PLAYER | shines a blue laser to read a Blu-ray or HD DVD disk and a red laser to read a regular DVD. Photodiodes sense the reflection.

DIAGRAM: DUAL-LAYER BLU-RAY DISK stores data at two levels, which are read by a laser that reflects off both.

DIAGRAM: BLU-RAY AND HD DVD DISKS pack more data than CDs or DVDs. The data pits, which constitute the digital 1s and Os, can be smaller because they are read by a blue-violet laser, which has a shorter wavelength than a red laser. Positioning the data layer closer to the laser also enables a tighter focus and less distortion and thus smaller pits and tracks.”

Summary: Both Blu-ray and HD DVD produce the same sharpness of image, but Blu-ray holds 25 GB of information while HD DVD holds only 15 GB. This difference is due to HD DVD using “MPEG-4 data-compression scheme rather than the MPEG-2 scheme still used by Blu-ray” (Fischetti 2007).

CD    DVD     HD DVD    Blu-ray

Single-layer disk capacity (GB)   0.7     4.7       15         25 Laser wavelength (nm)             780     650      405        405 Minimum pit length (μm)           0.8     0.4      0.2       0.15 Track pitch (μm)                  1.6    0.74      0.4       0.32 Table 1: (Fischetti 2007)

“DIAGRAM: COMBINATION PLAYER | shines a blue laser to read a Blu-ray or HD DVD disk and a red laser to read a regular DVD. Photodiodes sense the reflection.

DIAGRAM: DUAL-LAYER BLU-RAY DISK stores data at two levels, which are read by a laser that reflects off both.

DIAGRAM: BLU-RAY AND HD DVD DISKS pack more data than CDs or DVDs. The data pits, which constitute the digital 1s and Os, can be smaller because they are read by a blue-violet laser, which has a shorter wavelength than a red laser. Positioning the data layer closer to the laser also enables a tighter focus and less distortion and thus smaller pits and tracks.” (Fischetti 2007).

Fischetti, Mark (2007) Blu-ray vs. HD DVD. Scientific American, Vol. 297 No. 2: pp. 98-99.

"Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer electronics, personal computer and media manufacturers (including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc. This extra capacity combined with the use of advanced video and audio codecs will offer consumers an unprecedented HD experience.

While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on a red laser to read and write data, the new format uses a blue-violet laser instead, hence the name Blu-ray The benefit of using a blue-violet laser (405nm) is that it has a shorter wavelength than a red laser (650nm), which makes it possible to focus the laser spot with even greater precision. This allows data to be packed more tightly and stored in less space, so it's possible to fit more data on the disc even though it's the same size as a CD/DVD.

Blu-ray is currently supported by about 200 of the world's leading consumer electronics, personal computer, recording media, video game and music companies. The format also has support from all Hollywood studios and countless smaller studios as a successor to today's DVD format.

Technical Differences According to the Blu-ray team: "Because Blu-ray utilizes a lens with a greater numerical aperture than HD-DVD, the laser spot can be focused with greater precision to fit more data on the same size disc. This allows Blu-ray to hold 25GB per layer (50GB on a dual-layer disc), whereas HD-DVD can only hold 15GB per layer (30GB on a dual-layer disc). Blu-ray has also adopted a higher data transfer rate for video and audio (54Mbps vs 36.55Mbps)." Remember, though, that according to the technical specs, Beta was a better video format than VHS too... More importantly, the 15GB of HD DVD is claimed to be "just enough to fit a high-def movie", except if you're a movie fan, you already know that movies can vary in length from 80 minutes to over three hours. Having a movie split onto two disks is a terrible solution, and this is one of the reasons I prefer Blu-ray, personally. The Cost of a Player Price-wise, however, there's also a big difference. HD DVD players are in the $500 range, while Blu-ray pictures are $1000 or more coming out of the gate. The disks themselves should be a roughly similar price but, needless to say, if you buy a movie in one format and put it into a player for the other it's not going to work (however regular DVD movies will play fine in either high-def player)."

Blue-ray.com (Nov 19 2008) http://www.blu-ray.com/info/

"The basic principles for both Blu-ray and HD DVD are the same. An optical laser embeds code onto a disc as it spins, altering its surface, storing data from the centre of the disc outwards. Information is extracted off the disc by a laser of the same frequency that interprets the reflections of the laser off the discs surface.

The amount of data a disc can store is down to the frequency of the laser used when making the disc, and only drives using the same frequency laser can extract that same information. The newer technologies essentially use a laser that emits towards the blue (higher frequency) end of the spectrum. This allows a lot more data to be stored on the disc, greatly increasing capacity and launching us into a new optical age. Many will be aware of the “format-wars” between Betamax and VHS in the early 1980’s. General consensus would seem to imply there is currently a newer technological war brewing between Blu-Ray and HD-DVD that could rival it. Does this mean one format will never be used? Chances of that happening are very unlikely, it is important to remember that both HD-DVD and Blu-ray have been released for different markets. Blu-ray launched with the intention of dominating the Information Technology sector, where as HD-DVD aims to be dominant in the consumer products sector, essentially with audio-visual devices. Although neither of the formats have been released in the UK as yet, the early part of 2006 will see a flurry of activity, with many computer components being developed to cater for both Blu-ray and HD-DVD."

Cd-Writer.com (Nov 19 2008) http://www.cd-writer.com/blu_ray_faq.html

Total Summary:

During the “war” to see which high definition DVD format would be used, Warner Brothers, Apple, Dell, HP, and Samsung Electronics supported the use of Blu-ray, made by Sony, while Microsoft and Intel support supported HD DVD format, made by Toshiba (Unknown 2005). Both Blu-ray and HD DVD produce the same sharpness of image, but Blu-ray holds 25 GB of information while HD DVD holds only 15 GB. This difference is due to HD DVD using “MPEG-4 data-compression scheme rather than the MPEG-2 scheme still used by Blu-ray” (Fischetti 2007). CD    DVD     HD DVD    Blu-ray

Single-layer disk capacity (GB)   0.7     4.7       15         25 Laser wavelength (nm)             780     650      405        405 Minimum pit length (μm)           0.8     0.4      0.2       0.15 Track pitch (μm)                  1.6    0.74      0.4       0.32 Table 1: (Fischetti 2007)

A multilayer blue ray disk can hold as much as 50 GB of data on it. This increase in holding capacity (in comparison to a standard DVD) is due to the fact that blue ray utilizes a blue-violet laser rather than a red one. The blue laser has a shorter wave length and therefore can be focused with greater precision, allowing “the data pits, which constitute the digital 1s and Os, [to] be smaller” (Fischetti 2007). This allows for data to be stored closer together on the disk and thereby increases the storage capacity. Recent developments have added as many as 20 layers to the new discs, increasing the storage capacity to 500GB (Blu-ray.com).