DVD is an ultra-high-density optical disc that spans audio, audiovisual, and multimedia. It is called Digital Video Disc, which is a digital video disc, but it is also called Digital Versatile Disc. It is a digital versatile disc. The horizontal resolution of a DVD disc can be Up to 530 lines or more. The DVD emphasizes its universal features: its wide range of applications, comprehensive functions, and outstanding quality are unmatched.
Classification of DVD Discs The true meaning of DVD includes five types of specifications, namely, DVD Video (DVD Video Disc) and DVD Audio (DVD Disc). DVD--ROM (DVD ROM disc for computer), DVD--R (DVD disc recordable at one time), DVD--RAM (DVD disc recordable many times). According to the structure, DVD discs have the following types: D5 and D9, as well as D10 and D18 which are less frequently encountered by everyone. According to physical characteristics, the scientific name of D5 disc is "single-sided single layer", D10 is "double-sided single layer", D9 is "single-sided double layer" and D18 is "double-sided double layer". Each layer can accommodate a certain amount of data, that is, "one-sided single-layer" DVD has the smallest space, and "double-sided double-layered" DVD is the largest space. The larger space can accommodate a larger amount of data, so the amount of data the D9 can hold is almost double that of the D5, which is why the D9 disc usually has better sound quality and tidbits. At present, most DVD discs are single-sided single-layer, single-sided double-layered. There are two types of discrimination: single-layer discs are silver-white on the surface, and double-layered discs are golden yellow. If two serial numbers are printed on the disc, it is also a double layer. Double-sided single-layer and double-sided double layers are only used in some special occasions because of their high production cost. The capacity in the table below is the nominal capacity, and the actual capacity is 4.37GB, 7.95GB, 8.74GB, and 15.90GB in ascending order.
Anti-piracy Measures for DVD Videos Pirated CDs and VCDs have caused huge economic losses for publishers, film distributors, singers, and even the country. Hollywood movie companies have suffered too much in this area. In the new DVD video CD-ROM, a number of measures to protect the copyright of video and audio have been added, mainly including a zone code protection mechanism and four kinds of copy prevention CPS, CGMS, CSS (Content Disturbance System) and DCPS (Digital Copy Protection System).
CSS is mainly designed to prevent DVD movies from being copied illegally. Although you can open a CD by a computer and see that there is a directory structure, you can't copy content to a hard disk, especially a movie file (*.VOB). This is because the legitimate receiver of the video file data stream is not the hard disk but the Mpeg decompression engine (software or hardware). Secondly, even if the contents of the DVD are copied out, the contents of the movie are scrambled and cannot be restored during playback. If the DVD movie is output to a video recorder, can it be transcribed? However, the film company also think of this point, this is the DCPS protection system, because the DCPS will interfere with the analog signal during the transcription, so the video tape is certainly not recorded.
In addition, the regional code protection mechanisms formulated by the eight major movie companies also effectively prevent the piracy epidemic. According to the division of the eight major movie companies, the world is divided into eight regions. Except that the seventh region is the reserved region and the eighth region is the more specific region, the remaining six regions represent some of the global Specific area. Home DVD players or DVD drives that are currently sold everywhere can only play DVD movies corresponding to area codes. For example, machines purchased in our country can only play six-area DVD movies.
District 1: Canada, United States, East Pacific Island Region Zone 2: Japan, Europe, West Asia, Arabian Peninsula, South Africa, Egypt, Greenland Region 3: China Taiwan, Hong Kong Special Administrative Region, South Korea, South East Asia Region No. 4: Australia, New Zealand, Central and South America, South Pacific Islands Region 5: Africa, India Peninsula, Central Asia, Mongolia, Russia Region 6: China
Classification of DVD Discs The true meaning of DVD includes five types of specifications, namely, DVD Video (DVD Video Disc) and DVD Audio (DVD Disc). DVD--ROM (DVD ROM disc for computer), DVD--R (DVD disc recordable at one time), DVD--RAM (DVD disc recordable many times). According to the structure, DVD discs have the following types: D5 and D9, as well as D10 and D18 which are less frequently encountered by everyone. According to physical characteristics, the scientific name of D5 disc is "single-sided single layer", D10 is "double-sided single layer", D9 is "single-sided double layer" and D18 is "double-sided double layer". Each layer can accommodate a certain amount of data, that is, "one-sided single-layer" DVD has the smallest space, and "double-sided double-layered" DVD is the largest space. The larger space can accommodate a larger amount of data, so the amount of data the D9 can hold is almost double that of the D5, which is why the D9 disc usually has better sound quality and tidbits. At present, most DVD discs are single-sided single-layer, single-sided double-layered. There are two types of discrimination: single-layer discs are silver-white on the surface, and double-layered discs are golden yellow. If two serial numbers are printed on the disc, it is also a double layer. Double-sided single-layer and double-sided double layers are only used in some special occasions because of their high production cost. The capacity in the table below is the nominal capacity, and the actual capacity is 4.37GB, 7.95GB, 8.74GB, and 15.90GB in ascending order.
Anti-piracy Measures for DVD Videos Pirated CDs and VCDs have caused huge economic losses for publishers, film distributors, singers, and even the country. Hollywood movie companies have suffered too much in this area. In the new DVD video CD-ROM, a number of measures to protect the copyright of video and audio have been added, mainly including a zone code protection mechanism and four kinds of copy prevention CPS, CGMS, CSS (Content Disturbance System) and DCPS (Digital Copy Protection System).
CSS is mainly designed to prevent DVD movies from being copied illegally. Although you can open a CD by a computer and see that there is a directory structure, you can't copy content to a hard disk, especially a movie file (*.VOB). This is because the legitimate receiver of the video file data stream is not the hard disk but the Mpeg decompression engine (software or hardware). Secondly, even if the contents of the DVD are copied out, the contents of the movie are scrambled and cannot be restored during playback. If the DVD movie is output to a video recorder, can it be transcribed? However, the film company also think of this point, this is the DCPS protection system, because the DCPS will interfere with the analog signal during the transcription, so the video tape is certainly not recorded.
In addition, the regional code protection mechanisms formulated by the eight major movie companies also effectively prevent the piracy epidemic. According to the division of the eight major movie companies, the world is divided into eight regions. Except that the seventh region is the reserved region and the eighth region is the more specific region, the remaining six regions represent some of the global Specific area. Home DVD players or DVD drives that are currently sold everywhere can only play DVD movies corresponding to area codes. For example, machines purchased in our country can only play six-area DVD movies.
District 1: Canada, United States, East Pacific Island Region Zone 2: Japan, Europe, West Asia, Arabian Peninsula, South Africa, Egypt, Greenland Region 3: China Taiwan, Hong Kong Special Administrative Region, South Korea, South East Asia Region No. 4: Australia, New Zealand, Central and South America, South Pacific Islands Region 5: Africa, India Peninsula, Central Asia, Mongolia, Russia Region 6: China
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