CD
CD stands for compact laser disc, a general term used for all CD media formats. The CD formats available on the market include audio CD, CD-ROM, CD-ROM XA, photo CD, CD-I and video CD and so on. Among the various CD formats, perhaps the most familiar one is audio CD, which is a standard CD format used to store sound signal tracks such as music and songs. CD Digital Audio Signal (CDDA) was introduced by Sony and Philip as a form of music distribution during 1980. Because of the great success of audio CDs, the use of this media has been expanded to data storage for the purpose of data archiving and delivery. Compared with various traditional data storage media such as floppy disks and audio tapes, CD is the most suitable for storing large amounts of data. It may be any form or combination of computer files, audio signal data, photo image files, software applications and videos. Data. The advantages of CD include durability, convenience, and effective cost.
VCD is the abbreviation of Video Compact Disc: video compression disc. The VCD standard was jointly formulated by Sony, Philips, JVC, Panasonic and other electrical appliance manufacturers in 1993, and is a white paper standard for digital optical discs.
Technical Specifications
VCD is a video standard with full dynamic and full screen playback. Its format can be divided into:
The resolution is 352x240 pixels, 29.97 frames per second (suitable for NTSC TV playback);
The resolution is 352x240 pixels, 23.976 frames per second Picture;
The resolution is 352x288 pixels, 25 frames per second (suitable for PAL TV playback).
On the whole, the resolution is about a quarter of the resolution of the corresponding TV system. VCD video uses MPEG-1 compression coding, and audio uses MPEG 1/2 Layer 2 (MP2) coding. The code rate is 1150kbit/s for video and 224kbit/s for audio. The overall video quality is comparable to VHS tapes.
Because the bit rate of VCD is equivalent to that of ordinary music CD, a standard 74-minute CD can store approximately 74 minutes of video in VCD format.
VCD standard
VCD has three official standards: 1.0, 1.1 and 2.0:
1.0: the original version.
1.1: Revised version.
2.0: Added playback menu function (PBC), clear still picture playback function (704x480 or 704x576 pixels) and support for 352x288/25fps format.
(3.0: Many people have said that there is version 3.0, but no finished product has been published.)
VCD application
VCD is widely used in Asia . In Hong Kong, VCD and DVD have completely replaced video tapes and laser discs in the distribution market.
VCD is considered to be replaced by DVD, but due to some of its characteristics, it will remain in the market for a period of time.
VCD does not have the same region code restrictions as DVD, which means it can be viewed on any compatible machine.
Due to cost issues, some programs will not produce DVD or VHS videotape versions, and buyers can only purchase VCD versions.
VCD is cheaper than DVD, and the production cost is also lower. Of course, VCD lacks many additional features provided by DVD, such as subtitles, powerful menu functions (used for making highlights) and so on.
DVD
The full name of DVD was Digital Video Disc (Digital Video Disc) at the beginning of its birth. It is the successor product of CD/LD/VCD. It only took more than a year for DVD to develop its initial specifications in the second half of 1994 to the appearance of prototypes in early 1996. It can be described as a rapid development and is a new-generation standard storage technology recognized by the entertainment industry. Moreover, the computer industry has responded very positively to it.
In the early 1990s, the American Film Production Advisory Committee drafted a wish letter representing the seven major Hollywood film production companies. One of them was to require a standard to be recorded on a CD Video programs of length (135 minutes), and require higher image and sound quality than LD. It is necessary to know that the image resolution of VCD is only 352×240 (NTSC format) or 352×288 (PAL format). Obviously, the video performance alone cannot meet the above requirements. In view of the influence of Hollywood Film and Television Group in the world entertainment industry, hardware manufacturers have begun new efforts. It can be said that this is the motivation for the development of DVD.
In the spring of 1994, the seven major Hollywood studios Warner, Columbia, 20th Century Fox, Paramount, Universal, UA, MGM, White Disney and Viacom formed an organization-"HDVA Group "Considering that digital high-definition televisions will gradually become popular in the home, home-based digital high-quality movies will have great market potential, so they jointly initiated the initiative.
At the same time, the MPEG working group also developed the MPEG-2 compression coding scheme in 1991. At the same resolution, it has much higher compression quality than MPEG-1 (average compression The ratio is about 1:40), but if you use high resolution (later DVD resolution is 720×480 [NTSC format] and 720×576 [PAL format] resolution), the storage medium must have a larger capacity , The data rate is higher (the highest is nearly 10Mb per second, while VCD is only 1.15Mb). But the premise was that the MPEG-1 standard was adopted in order to take care of the usability of existing equipment and CD discs. To adopt the MPEG-2 standard, it is necessary to develop a larger capacity optical disc and brand new reading and recording equipment, so the development of a large-capacity optical disc system becomes the first priority.
In December 1994, the camp headed by Philips and Sony, and the camp headed by Toshiba and Time Warner started a DVD specification dispute. It was not until December 1995 that the American film and computer companies were strongly urged. , Finally reached a unified specification.
September 15, 1995 was a crucial day for DVD, and the two camps finally reached an agreement to unify DVD standards. At the last juncture, Sony made a major and crucial concession. She gave up her own optical disc structure and agreed to adopt Toshiba's unique and more advanced dual-disc docking optical disc structure, and Toshiba responded to the data signal. Part of the technology of modulation and processing is compromised by Sony, which has rich experience in CD production and development.
EVD
EVD uses DVD discs as storage media and uses H264 video compression standards.
Thanks to the advanced compression method, EVD provides much higher picture quality than DVD-Video on the same disc.
EVD (Enhanced Versatile Disk) means enhanced multimedia disk system, commonly known as "a new generation of high-density digital laser video disk system", which is an upgraded product of DVD. The resolution of EVD products is five times that of DVD. In terms of sound effects, it is the first time in the world to achieve both high fidelity and surround sound. An EVD disc can store about 110 minutes of audio and video programs. Relevant experts pointed out that EVD perfectly combines shocking sound effects and beautiful picture quality. It is the first time in the world to realize the storage and playback of high-definition digital programs based on optical discs, bringing the Chinese people a high-definition era DVD player
Compared with Super VCD and DVD, EVD technology has obvious advantages. Product performance indicators show that the difference between EVD and DVD is first of all high-definition. The pixel of EVD is nearly 5 times larger than that of DVD, and it can receive digital TV programs; it has a unique "erasable function" that can directly record programs and save The broadcast program is directly burned into a CD; it is fully compatible with the computer, through which the home appliances and the computer can be connected, and the information network within the family can be established. According to the estimates of professionals, the industrial scale of EVD will reach the annual production capacity of more than 10 million DVD players, 200 million discs, and the supporting production capacity of related devices to exceed 10 million sets.
EVD is made in China in the true sense: it has independent intellectual property rights, masters core technology, and controls the right to formulate and modify standards. EVD is a new type of consumer electronic product with powerful functions and a wide range of uses. It integrates players with high-definition digital programs, high-fidelity and surround sound speakers, very large-capacity karaoke, video recorders, games, set-top boxes, Videophone, Internet function and a computer that can meet the needs of ordinary households are all in one. In addition, it can also be used as a testing and demonstration device for TV production and sales.
EVD supports the storage and playback of high-definition TV programs, and has obvious technical advantages over DVD: it has network browsing functions, supports car traffic navigation; supports family information network platforms and game console functions; established audio The world's leading position in compression; established a self-established standard, brought the Chinese people to the DVD player of the high-definition era, and also set a model for domestic related enterprises to expand their living space.
From the published EVD technology patents, it is mainly the filtering transformation of audio/video and the optimization method of encoding/decoding. The function is to improve the quality of the audio picture and increase the data compression ratio. In addition, there is a method of "dynamic superimposition of subtitles on digital video" inherited from SVCD, which can display subtitles in 256 colors. Including 5 software, namely "DVD-EVD conversion software", "AC3-EAC conversion software", "OGT production system", "EVD digital video disc production system" and "VCD/DVD/EVD player". "EVD" is a digital optical disc system with independent intellectual property rights owned by the Chinese, and it is also a national standard in the field of digital optical discs in China. The technical specifications of the EVD system have been submitted to the International Electrotechnical Organization and the International Organization for Standardization, and are expected to become an international standard. Provide users with clearer programs. Based on the original DVD technology, the EVD system nearly doubles the stream speed, and the image resolution reaches 5 times that of DVD, achieving more shocking sound, more beautiful subtitles and more flexible choices. .
Burning a data disc
Take Nero Burning ROM as an example to introduce the method of making a normal DVD data disc:
Step 1, put it in the DVD burner Burn a blank DVD disc, and then click "All Programs" → Nero 7 Premium → "Data" → Nero Burning ROM command in the Start menu to run the Nero Burning ROM program.
Step 2, in the "New Edit" dialog box that opens, first click the drop-down triangle button in the upper left corner and select the type of disc (DVD or CD) to burn from the drop-down list. Select the DVD option, and select the DVD-ROM (ISO) option in the DVD disc type list below. Then select the "No Multiple Sections" radio button in the "Multiple Sections" area on the right, and click the "New" button.
Step 3, open the main window of the Nero Burning ROM program, and click the "Burner" → "Select Burner" menu command in turn.
Step 4, in the open "Select Burner" dialog box, click to select the DVD burner to be used, and click the "OK" button.
Step 5, return to the main window of the Nero Burning ROM program, and select the DVD disc type (DVD9 or DVD5) you are using in the lower right corner of the window. This example uses DVD5 disc.
Step 6, find the data to be burned to the DVD disc in the "File Browser" tab of the "Browser" pane, and then select and right-click the data, in the open shortcut Select the "Copy to Edit" command in the menu.
The total amount of data selected should be less than the capacity of the DVD disc (that is, it must be less than 4483MB).
Step 7, confirm that the total amount of data selected does not exceed the capacity of the DVD5 disc, and then right-click the small disc icon (namely the disc name) at the top left of the main window of the Nero Burning ROM program. Select the "Rename" command in the shortcut menu to rename the disc (such as Data200707).
Step 8, click "Burner" → "Burn Compile" menu command in turn.
Step 9, open the "Burn Compile" dialog box, in the "Burn" tab you can set the disc writing speed and the number of burned copies. Click the drop-down triangle button on the right side of "Write Speed". In the drop-down list, it is recommended to select a lower writing speed (4X in this example). The lower writing speed can effectively improve the burning success rate and the compatibility of the disc. Enter the number of copies to be burned, and finally click the "Burn" button.
Step 10, Nero Burning ROM starts to burn. Depending on the amount of burned data and the set burning speed, the time required to complete the burning is also different. No human involvement is required during the burning process.
Step 11, after the burning is completed, the message box after burning is automatically opened. Click the "Burn again" button to burn a second copy of the same disc, click the "OK" button to close the message box, and the disc will automatically pop up.