1In the spring of 994, the organization "HDVA Group" composed of seven Hollywood film companies, namely Warner, Columbia University, 20th Century Fox, Paramount, Universal, UA, MGM, White Disney and Viacom, thought that digital high-definition TV would be gradually popularized in the family, and the domestic digital high-quality movies had great market potential, so they jointly initiated the production of DVD. 199465438+In February, the camp led by Philips and Sony launched a DVD specification dispute with the camp led by Toshiba and time warner Inc.. Until199565438+February, under the strong urging of American film and computer manufacturers, a unified specification was finally reached.
The data capacity of DVD is about 7 times that of VCD. This is because DVD and VCD use the same technology to read the data buried in the optical disc (optical reading technology), but because the light spot produced by the optical reading head of DVD is small (the original reading light spot size of 0.85μm is reduced to 0.55μm), the storage density of DVD data can be improved within the same optical disc area (the appearance size of DVD and VCD is the same), that is to say, the improvement of DVD data capacity can be said to be optical credit.
The DVD Alliance divides the world into 1-6 regions according to geographical regions, and each DVD player and DVD will be locked and can only be played in a certain region (the corresponding region code will be locked according to the region where the product is sold). For example, if Taiwan Province Province belongs to Zone 3, then the DVD movie you bought in the United States (belonging to Zone 1) and the player you bought in Taiwan Province Province cannot be played. In other words, the lock code of the movie must match the lock code of the player (the movie in 1 area matches the player in 1 area, and the movie in area 2 matches the player in area 2) so that you can watch the movie smoothly! The area code list is currently divided into the following six regions in the world:
1 Zone: United States, Canada and East Pacific Islands.
The second area: Japan, Europe, West Asia, Arabian Peninsula, Egypt, South Africa and Greenland.
Area 3: Taiwan Province Province, Korea and East Asia.
Fourth area: Central and South America, Australia, New Zealand, South Pacific Islands.
Region 5: Africa, Indian Peninsula, Central Asia, Mongolia and the former Soviet Union.
The sixth district: Chinese mainland area.
There are five formats of DVD: DVD-VIDEO (which can be divided into movie format and personal computer format), DVD-ROM, DVD-R, DVD-RAM and DVD-AUDIO.
DVD disc specification
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Type layer capacity
Read-only standard definition
DVD-Video/DVD-ROM 1 1 4.7 GB(DVD-5)
DVD-Video/DVD-ROM 1 2 8.5 GB(DVD-9)
DVD- video/DVD-Rom219.4 GB (DVD-10)
DVD-Video/DVD-ROM 2 2 17.0 GB(DVD- 18)
Read-only high definition
Blu-ray (BD-ROM)1125.0gb.
Blu-ray (BD-ROM) 1 2 50.0GB
HD DVD read-only memory1115.0gb.
HD DVD read-only memory 1 2 30.0GB
Write once standard definition
DVD-R (A) 1 1 4.7GB
DVD-R (G) 1 1 4.7GB
DVD-R (G) 2 1 9.4
GB DVD-R DL 1 2 8.5GB
DVD+R 1 1 4.7GB
DVD+R DL 1 2 8.5GB
Write once high definition
Blu-ray (BD-R)1125.0gb.
Blu-ray (BD-R) 1 2 50.0GB
HD DVD-R 1 1 15.0 GB
HD DVD-R 1 2 30.0GB
Some people also call DVD a digital multifunctional disk, which integrates computer technology, optical recording technology and film and television technology to meet people's demand for large storage capacity and high performance storage media. DVD is not only widely used in audio/video field, but also will promote the development of publishing, broadcasting, communication, WWW and other industries. It has a wide range of uses, as can be seen from its five specifications:
DVD-ROM- CD of computer software, similar to CD;
DVD-video- home audio-visual CD, similar to LD or videocd.
Dvd-audio-music disc, similar to music CD;
DVD-r (or DVD-write-once)- A write-once DVD similar to CD-r;
DVD-RAM (or rewritable DVD)- An optical disc that can be read and written many times, and its use is similar to that of MO.
2. What are the main features of 2.DVD-VIDEO?
It is a high-quality video program with MPEG-2 standard.
It can support 4:3 full screen, 4:3PS, 16:9 morphing widescreen and other screen formats.
Supports up to 8 tracks of digital audio and 32 subtitles.
Each track can have up to 8 channels.
Up to 9 perspectives
Video automatic seamless switching
There are menus and simple interactivity.
Quick search by title, chapter and time
3. How is the area code of 3.DVD divided into regions?
Region 1 (Region 1): the United States, Canada and the East Pacific Islands.
Region 2: Japan, Western Europe, Northern Europe, Egypt, South Africa and the Middle East.
Region 3: Taiwan Province Province, Hongkong, Korea, Thailand, Indonesia and other Southeast Asian countries.
Fourth area (Region4): Australia, New Zealand, Central and South America, South Pacific Islands.
Region 5: Russia, Mongolia, Indian Peninsula, Central Asia, Eastern Europe, North Korea, North Africa and Northwest Asia.
The sixth district: Chinese mainland.
4. What are D5, D9, D 10, D 14 and D 18?
A DVD disc consists of an upper base and a lower base, and each base can hold up to two layers of data. The DVD optical head can read these two layers of data by adjusting the focal length. In the production process, the data is read out and the two substrates are bonded together to form a complete DVD disc.
Short for D5, DVD-5, SS-SL or single-sided single layer, with a maximum of 4.7G, with data printed on one side and characters or patterns printed on the other. More than two hours of video.
D9, short for DVD-9, is SS-DL or single-sided and double-layered, with a maximum of 8.5G, with data on one side and printed characters or patterns on the other. About 4 hours of video
D 10, abbreviated as DVD- 10, is a double-sided single layer (DS-SL or double-sided single layer) with a maximum of 9.7G, and both sides are data planes. About 4.5 hours of video
D14 DVD-14 (12 cm, double-sided/mixed layer) 12.32 GB (13.24 BB), about 6.5 hours of video.
D 18 and DVD- 18, that is, DS-DL or double-sided double layer, maximum 17G. Both sides are data planes. About 8 hours of video
DVD disc
The compressed CD is encoded by DVD base, DVD boot and directory, and the film is in VCD format.
Compressed DVD is basically the so-called DVD composed of standard resolution MPEG- 1 video format files in the DVD directory! In the eyes of many people in the industry, DVD video can only be encoded by MPEG-2, which is actually a misunderstanding. According to the technical specifications of DVD, MPEG- 1 and MPEG-2 are legal video coding formats. The DVD compressed disc guided by MPEG- 1(VCD) video recording group does not violate the DVD industry standard.
The popular compressed DVD in China uses MPEG- 1 video, and the bit rate is 1 150Kbps, which is the same as the standard VCD, so there is no problem that the image of DVD compressed disc is clearer than that of VCD. Audio coding adopts MPEG- 1/2 Layer II audio, and the sampling rate is 48kHz, slightly higher than 44.1kHz. VCD. Subtitles can be DVD standard subtitles or embedded subtitles. A 4.7GB DVD can hold more than 450 minutes of programs, which is about 8 to 10 episodes of TV series.
In addition, it should be noted that playing DVD compressed discs will not affect the life of the disc drive and optical head. However, some DVD players with poor VCD compatibility will feel a little fuzzy when watching compressed discs.
In many families in our country, the TV set is not digital high definition, and the sound is not AC3 or DTS. Watching movies on CD-ROM is an economical way.
Hd DVD
Advanced optical storage optical disk alliance (advanced optical disk; ; HD-DVD specification of AOD is designed based on the current standard DVD specification. HD-DVD completely inherits the same thickness of standard DVD data layer, but it adopts blue laser technology to the letter, but its wavelength is short, so it can store dense data on optical discs. Compared with the current standard DVD single-layer capacity of 4.7GB, the single-layer capacity of HD-DVD is 15GB, which is considered as a high-capacity optical storage technology.
The main selling point of HD-DVD specification is the structural design of sharing part between HD-DVD and standard DVD. DVD manufacturers don't want to upgrade specifications and invest heavily in updating production equipment. Blu-ray manufacturers must buy brand-new production equipment to produce new specifications.
The HD-DVD specification also continues the data structure of standard DVD (such as architecture, index and ECC block). Error proofreading algorithm comes from the module structure of standard DVD, and the only difference from standard DVD is that it is used to receive more error proofreading ECC blocks. Error proofreading of ECC blocks is continuous. In HD-DVD, one ECC block is equal to two linked ECC blocks of standard DVD.
In April, 2005, HD-DVD will adopt Advanced Access Content System (AACS), which is a more advanced version of CSS, and has been applied to the standard DVD specification, and obtained a good evaluation. The Patent Affairs Committee Association consists of IBM, Panasonic, Microsoft, Toshiba and Sony. Because Disney is a member of the BD camp, so is Warner.
Dan Lammer published a worrying report in the newspaper, in which he mentioned the name of independent safety assessor. ; ISE) investigates two anti-theft copy systems, AACS and SPDC (self-protected digital content). SPDC has appeared in HD-DVD security system and is considered by the Committee to be superior to AACS.
When producing DVD players, AACS will give each machine a set of 128-bit device keys, which can be used in a single device or shared with other multi-tasking devices. MKB(Media Key Block) is an anti-theft code legally authorized by AACS. This set of anti-theft codes can be decoded and restored. If the anti-theft code is destroyed, MKB will immediately regenerate and destroy the original anti-theft code to protect itself, so the anti-theft code cannot be recovered.
This design is very exciting, because if the anti-theft code of the DVD player is damaged and detected, unless the ROM read-only firmware is upgraded, the DVD will deadlock itself and cannot be started to avoid being copied, so people will hesitate to use it. AACS has built-in internet access function, which can link the CRM customer service management or content manipulation management of the website. So future online connection is inevitable.
SPDC has a mechanism to restore the DVD player, play back all DVD contents, and record and restore the searched recorded contents. Because the DVD player has a video recording function, if a DVD is damaged after being put into the DVD player, then your DVD player will become a security door latch, and start the self-protection and anti-lock and anti-theft functions.
In fact, the role of secret monitoring in the system is not limited to this. Even every time a DVD player plays a new disc, the SPDC self-protection and anti-lock mechanism will start immediately. Therefore, when the old CD is damaged, each new CD seems to be an informer, who will come forward and confess and record the truth on the RAM that can be permanently saved and can correct the firmware of the player.
The playback software named Divx is not compatible with SPDC, and Divx is just one of many incompatible softwares. If there are more incompatible software, it may lead to supporters of the original standard DVD specification and produce the psychology of rejecting HD-DVD specification.
HD stands for both high density (the storage capacity of the optical disc is larger) and high resolution (the picture quality is better). The first commercial Blu-ray HD-DVD came out in Japan in April this year. These DVDs can only be used for home recording, not for pre-made high-definition movies, and can only be used under the digital high-definition broadcasting system in Japan.
The new DVD format will not replace the current DVD format soon, but the new HD player can play the current DVD movies and make the picture look better through progressive scanning technology. But the new HD-DVD disc can't be played on the current DVD player. The DVD movies we have now can be played for many years. Think about it. In the United States, the HDTV system is expected to be launched at 1989, but it has not been finalized at 1996, and it has not been launched at 1998. Can HDTV eliminate existing TVs so quickly?
At present, HD-DVD has five candidate products. They are:
1 HD-DVD-9 (also known as HD-9)
This technology will enable a 2-hour movie to be stored on DVD-9 at the rate of 6-7 Mbps, and it can realize the progressive scanning of 24 frames and 720 lines per second. Compression methods can be MPEG-2 and MPEG-4.
Advanced compact disc (AOD).
It is also called DVD2. This format is modified from the existing DVD physical format, and realizes the single-layer storage of 15G data. This design is mainly to increase the storage capacity of data. At the same time, the existing DVD copying equipment can still be used in theory.
3 blue light (BD).
Blu-ray has adopted a new high-density physical format, so each layer can store 23-27G of data. Blu-ray technology can record 2 hours of digital HD video or more than 65,438+03 hours of standard TV broadcast programs (equivalent to the quality of video home system VHS, with a data stream of about 3.8Mbps).
Advanced optical storage research alliance (AOSRA), Blue-HD-DVD- 1.
5 Osra Blue DVD-DVD-2.
Both of them were initiated by Taiwan Province Institute of Industrial Technology and Advanced Optical Storage Research Alliance (AOSRA) established by 28 companies in June 2002.
Blue-HD-DVD- 1 adopts the structure of pasting two 0.6mm discs, and the single-sided single-layer capacity is 17GB, which is similar to AOD.
Blue-HD-DVD-2 adopts 1.2mm substrate (including 0. 1mm protective layer), and its single-sided single-layer capacity is 27GB, which is similar to that of Blu-ray disc. However, due to the different physical parameters such as track spacing and minimum recording point length, these two HD-DVD formats are not compatible with AOD and Blu-ray Disc.