[Edit this paragraph] 1。 DVD born 1, support MP4, DVD, VCD, MP3, CD player format 2, compatible with DVD-R, DVD-RW, CD-R, CD-RW CD-ROM media 3, to provide USB / SD port / card reader, supports a wide range of storage 4, long 45 seconds ESP electronic shock absorber system 5, large LCD screen LCD Display / Digital Clock 6, high / low electronic control 7, enhanced output, strengthen Bass 8, infra-red remote control 9, such as loudness control 10, high-quality digital FM / AM tuner 11, high-power four-channel power amplifier FET 45W × 4 12, straight into the front panel disc The full name of DVD, in the early days of the birth of the Digital Video Disc (digital video discs), now known as "Digital Versatile Disc", or "digital versatile discs" is a CD / LD / VCD / EVD product of the follow-up。
   DVD from the second half of 1994 to the preliminary specifications of the prototype in early 1996 appeared only more than a year, is developing rapidly and is recognized as a new generation of entertainment industry-standard memory technology。
   Moreover, the computer industry's response to its very positive。 The early nineties, the U。S。 film production industry advisory committee drafted a representative of the seven major Hollywood studios of the aspirations of the book, one of which is to be recorded on a CD in a standard length (135 minutes) video programs, and requested that LD is higher than the image and sound quality。
   VCD to know only the image resolution of 352 × 240 (NTSC format) or 352 × 288 (PAL standard), it is clear from the video performance will not be able to meet those requirements。
   In view of the Hollywood film and television group in the world the influence of the entertainment industry, hardware manufacturers also began a new effort, it can be said this is the cause of the development of DVD。
   The spring of 1994, the seven major Hollywood film company Warner, Colombia, 20th Century Fox, Paramount, Universal, UA, MGM, Walt Disney and Viacom formed an organization - "HDVA Group", taking into account the number of The high-definition television will be universal in the family gradually, the family of high-quality digital video will have great market potential, then the joint initiative。
   At the same time, MPEG working group in 1991, also developed MPEG-2 compression coding schemes under the same resolution than MPEG-1 compression much higher quality (the average compression ratio of about 1:40) However, if the use of high-resolution (and later DVD's resolution is 720 × 480 [NTSC format] and 720 × 576 [PAL format] of the resolution), storage capacity of media to be even greater, a higher data rate (per second highest near 10Mb, while the VCD only 1。
  15Mb)。 However, the premise was to take care of the existing equipment and CD discs can be used, while the use of the MPEG-1 standard。
   To the use of MPEG-2 standard requires the development of greater capacity and a new CD-ROM reading and recording equipment, so the development of large-capacity optical disk system to become the top priority。
   December 1994, Philips and Sony-led camp, with Toshiba and Time Warner began a campaign led by the dispute over DVD specifications until December 1995, film and computer in the United States strongly urged to finally reach a unified standard。
   September 15, 1995 for the DVD is a key day, the two camps finally reached agreement on unified DVD standard。 At the last minute, Sony has made significant concessions on the key, she gave up the structure of their own CD-ROM, Toshiba agreed to take more advanced and original double-disc CD-ROM docking structure, and Toshiba are the corresponding data signal modulation, processing technology to the rich part of the CD production and development experience of the Sony compromise。
   [Edit this paragraph] 2。 DVD Forum DVD Forum, this DVD set up shortly after the birth of the organization is the development of DVD has a major impact on the industry as it is the only official DVD。
   In theory, any DVD-related standards and must go through its approval。 Called the DVD Forum DVD Forum, established in April 1997, the predecessor is the end of 1995, the DVD set up Union (DVD Consortium) 10 DVD from the composition of the main manufacturers, also known as 10C, to the Chinese DVD manufacturers charged patent that they -- - Hitachi, Matsushita, Mitsubishi, Philips, Pioneer, Sony, Thomson, Time - Warner, Toshiba and JVC。
   In this paper, when the deadline, DVD Forum, a total of 212 member companies, and currently three other major research and development of DVD recorders / Promotion Organization - RWPPI, RDVDC, DVD + RW Alliance members have all the basic are the DVD Forum members, Therefore, it is a DVD of the development of the most influential organizations in the industry is not an exaggeration。
   [Edit this paragraph] 3。 Physical structure The most common DVD, that is, single-sided single-layer DVD data capacity of about 7 times the VCD, because DVD and VCD is to use the same technology to read the hidden information in the CD-ROM film (optical reading technology ), but as a result of DVD optical read head generated by the smaller spot (to be read the original 0。
  85μm spot size down to 0。55μm), therefore in the same area the size of the disc (DVD and VCD of the appearance of the size of is the same), DVD data storage density can be improved, in other words, DVD data capacity enhancement can be said that thanks to advances in optical read head thanks。
   Disc diameter: 120 mm Disc thickness: 0。6 mm / side Laser wavelength: 635-650 nm Numerical aperture: 0。6 Optical channel spacing: 0。
  74 μm Bump minimum pit length: 0。4 μm The length of error-correcting codes: RS-PC Modify signal modulation: 8-16 The utilization of disc surface: 86。
  6 square centimeters Number of bytes per sector: 2048-2060 bytes / sector [Edit this paragraph] 4。 DVD Category There are five or DVD format DVD-VIDEO (film format and can be divided into PC format), DVD-ROM, DVD-R, DVD-RAM, DVD-AUDIO DVD-Video for watching movies and other visual entertainment。
   If using double-sided and each side and double-decker, with a total capacity of 17GB。 DVD-ROM and DVD Video basic skills, but it contains computer-compatible file format。
   Used to store data。 DVD-R capacity is 4。7GB。 Actually created for professional and general users to use the two versions。
   Users to write DVD-R only once。 DVD-RAM This makes DVD a virtual hard disk can be used to random access。 The original drive is a 2。
  6GB capacity can be increased to one side 4。7GB。 Can be rewritten 100,000 times。 DVD-RW similar to DVD-RAM, but the use of the order of reading - write access, like DVD-R instead of the hard disk。
   Each side of the time - to write the capacity of 4。7GB。 Can be rewritten 1000 times。 DVD-Audio up-to-date than the standard CD audio format for the fidelity of a good double。
   [Edit this paragraph] 5。 DVD-Video area code DVD Union according to geographic regions around the world is divided into 1-6 areas, and each and every DVD player a DVD will be locked in a certain area can only play (depending on the sale of products of the region corresponding to the locked area code )。
   For example: Taiwan belongs to the first 3 areas, so you are in the United States (belonging to Zone 1) to buy the DVD movie you will not be able to use to buy in Taiwan to play the player, that is, encrypted video player must be encrypted (No。
   1 District No。 1 movie with the player area, Area 2 of the video with the No。 2 player area。) you can watch videos smoothly! region code list of the world is divided into the following six areas: [Note: production mainland player can support most of the six areas] First District: United States, Canada, East Pacific Islands area。
   Zone II: Japan, Europe, West Asia, Arabian Peninsula, Egypt, South Africa, Greenland。 Third District: Taiwan, South Korea, East Asia。
   Fourth District: Central and South America, Australia, New Zealand, the South Pacific island。 Fifth District: Africa, Indian subcontinent, Central Asia, Mongolia, the former Soviet Union region。
   Sixth District: Mainland China。 [Edit this paragraph] 6。 DVD disc specifications The type of surface layer capacity Read Only Standard Definition DVD-Video/DVD-ROM 1 1 4。
  7GB (DVD-5) DVD-Video/DVD-ROM 1 2 8。5GB (DVD-9) DVD-Video/DVD-ROM 2 1 9。4GB (DVD-10) DVD-Video/DVD-ROM 2 2 17。0GB (DVD-18) Read Only High Definition Blu-ray (BD-ROM) 1 1 25。
  0GB Blu-ray (BD-ROM) 1 2 50。0GB HD DVD-ROM 1 1 15。0GB HD DVD-ROM 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) 1 1 25。
  0GB Blu-ray (BD-R) 1 2 50。0GB HD DVD-R 1 1 15。0GB HD DVD-R 1 2 30。0GB [Edit this paragraph] 7。 DVD security DVD-Video using the Content Scrambling System approach to data protection, but the program as a result of leakage from a projection of all the key may have been the key to break the DVD John。
   DVD-Audio uses Content Protection for Prerecorded Media way of data protection, as a result of the program after the leak in a key where the key group to exclude from the legitimate key, it is better security。
   [Edit this paragraph] 8。 DVD recording DVD burner of the development process Speaking of DVD burner in the development process, we can not fail to mention the birth of DVD and standards established。
   English DVD called "Digital Versatile Disc", or "digital versatile discs" is a CD / LD / VCD of the follow-up products。
   Preliminary specifications from the beginning of 1996 the DVD launch of the first prototype took only a year's time, is recognized as a new generation of storage technology standards。
   DVD of the birth and establishment of standards, and the rapid development of the entertainment industry is directly related to its predecessors, CD-ROM and VCD discs are breeding and therefore Health。
   The media giant's ever-increasing demands of the hardware manufacturers to stimulate the development of a new DVD。 Note: the early nineties, the U。
  S。 film production industry advisory committee drafted a representative of the seven major Hollywood studios of the aspirations of the book, one of which is to be recorded on a CD in a standard length (135 minutes) video programs, and requested that LD is higher than the image and sound quality (in mid-1990 to this request, an official has been identified in 1994)。
   VCD at a time when the image resolution is only 352 × 240 (NTSC format) or 352 × 288 (PAL format), video performance is far from sufficient to meet those requirements。
   December 16, 1994, Sony released the first "single-sided double-12CM (5。25 inch) high-density multimedia CD format and technology indicators", referred to as multi-media CD-ROM system (MMCD, Multi Media Compact Disc), which is DVD technical specifications first。
   At the beginning of the birth of the DVD, it is full of competition, Sony - Philips Group MMCD (single-sided double-layer structure) and Toshiba's SD (two-sided double-layer structure) engaged in a fierce fighting, although the final reconciliation between the two parties, But the struggle did not end completely, but has been extended to the DVD recorder between the specifications! As the CD recording technology has been very mature, and therefore achieve very realistic DVD burner。
   In the first DVD burner, before the birth, a vigorous dispute over the standard DVD burner began! To understand this complex dispute over DVD recording standards, first of all, can not fail to mention the birth of a DVD shortly after the establishment of the development of the DVD is the DVD has a significant impact on the only official organization: DVD Forum。
   This was established in April 1997 of the DVD Societies (DVD Consortium) 10 DVD from the composition of the main manufacturers, also known as 10C, to the Chinese DVD manufacturers charged patent that they - Hitachi, Matsushita, Mitsubishi, Philips, Pioneer, Sony, Thomson, Time - Warner, Toshiba and JVC。
   At present, three other major research and development of DVD recorders / Promotion Organization - RWPPI, RDVDC, DVD + RW Alliance members have all the basic are the members of the DVD Forum。
   In theory, any DVD-related standards and must go through its approval。 However, after the unification of DVD specifications, DVD Forum DVD burner does not have a unified standard, and its organization is not a mandatory。
   In the DVD standards battle in the failure of the Philips and Sony Corporation in 1996 as soon as the formal launch of DVD, it can not wait for the development of recordable DVD, and Hewlett-Packard co-founded with the DVD + RW Alliance, it is the DVD + RW DVD + R with the norm-makers。
   At the same time, Pioneer is also produced in 1997 its recordable DVD technology - DVD-R, as well as after the DVD-RW, as a result of market-oriented and mainstream DVD Video DVD-RAM is an important supplement to the weaknesses, Therefore, the rapid adoption of the DVD Forum's certification, as the official designation of non-DVD data storage applications recordable DVD standards (DVD-R and DVD-RAM at the same time through the DVD Forum)。
   This, DVD recording technology on the emergence of three categories, five kinds of norms (DVD-RAM, DVD-R/RW, DVD + R / RW), recordable DVD standard the following is the development of the summary table: 1996 DVD-ROM, DVD-Video 1997 DVD-RAM (Ver1。
  0; 2。6GB) DVD-R (Ver1。0; 3。95GB) 1998 DVD-R (Ver1。9; 4。7GB) 1999 DVD-Audio DVD-RAM (Ver2。0; 4。7GB) DVD-RW (Ver1。0; 4。7GB) DVD + RW (3。
  0GB) 2000 DVD-RAM (Ver2。1; 4。7GB) DVD-R (Ver2。0; 4。7GB / writer type) DVD-R (Ver2。0; 4。7GB / Universal) DVD-RW (Ver1。1; 4。
  7GB) DVD + RW (Ver0。9; 4。7GB) 2001 DVD + RW (Ver1。0; 4。7GB) DVDMulti (Ver0。9) DVDMulti (Ver1。0) DVD + RW (Ver1。1; 4。7GB) 2002 DVD + R (Ver1。
  0; 4。7GB) Relatively speaking, DVD + RW is the most advantage of the three standards, which move in the recording and music video media better than DVD-RW, along with Microsoft's involvement is a huge market potential is likely achievements of a unified standard DVD recorder。
   However, in a variety of factors, the three different standards are basically a "separation of the three" situation。
   The two competing, incompatible formats, all strive to become the industry standard, the two formats can store video and data, but are not compatible to the users and the confusion which products to buy, so the market At the same time, there was support for both formats of DVD burner。
   In order to win the support of more users, more and more are also compatible with other DVD specifications。 This represented a BenQ DW800A。
   Some明基特disc through易容术- Book Type Management ", can easily burn out the DVD + R / RW disc to change the parameter declaration format for DVD-ROM, CD-ROM or DVD regardless of the family DVD player can easily read out, the compatibility of 99%。
   Specifications on the DVD recorder continues to quarrel, and since May 2001, the Netherlands, Philips launched the global market to the first DVD Recorder - DVDR1000, more and more manufacturers of optical storage quickly follow-up rate of new product development to accelerate, with the expansion of production capacity, DVD burner to the reason the prices are moving。
   At the end of 2003, BenQ DW400A below 1,000 mark, a DVD burner perfect storm of mass popularity started。 This is also confirmed in May 2001 in the global market the first DVD burner predicted at the time of the official birth: not two years, DVD will be audio-visual life of the people rule! Mainstream DVD burner specifications DVD-RAM DVD-RAM using Phased-changed Dual technology and partially from MO, with a capacity of at least 2。
  58GB, to a maximum of 4。7GB。 DVD-RAM earlier been a mechanical protection, and users must not even shell and Add DVD-RAM read and write DVD-RAM write data to the device。
   The latter has been developed under another shell in addition to the DVD-RAM, but still need to write data before its shell。
   At present, the double-sided DVD-RAM has lowered the choice of shell。 The first generation of DVD-RAM at launch in June 1998, one year after the launch of version 2。
  0, capacity has been upgraded to 4。7GB, Panasonic and Hitachi were launched in 1999 to support the DVD-RAM of DVD-ROM。 DVD-R DVD-R just like CD-R, like the use of organic dyes are made of the method, the majority of readers and DVD players support DVD-R, the beginning of the DVD-R capacity is only 3。
  95GB, late expanded to 4。7GB , early DVD-R is divided into two categories: DVD-R (G) and DVE-R (A), DVD-R (A) is for the professional market, the use of 635-nm laser to write data, as early as in 1997, 10 PIONEER months from the introduction of version 1。
  0, in May 1999 until the introduction of 4。7G DVD-R (A) 1。9 version Features: DVD-R (A) can not write to recordable DVD-R (G), contrary to DVD-R (G) burner can not write DVD-R (A) DVD-RW DVD-RW formerly known as DVD-R / W, 1999 on 12 years in Japan Pioneer's DVD-RW home video recorder。
   DVD-RW as CD-RW, as can be rewritten more than 1,000 times。 DVD-RW and DVD-R using the same Track Pitch, Mark Length and RotationControl, all Pioneer, Sharp and Zenith's DVD function to read DVD-RW。
   DVD-RW discs have three, 1。0 version of the DVD-RW in Japan, a country other than the very few opportunities to find the most important thing is this type of DVD-RW compatibility is not high。
   1。1 version of the DVD-RW joined the Pre-Recorded Lead-in technology to improve compatibility。 Finally, a DVD-RW 1。1 is the B version, B version contains a unique ID, can copy protected DVD-ROM。
   Three kinds of DVD-RW is the capacity of 4。7GB。 。 Characteristics: the advantages of good compatibility, ability to DVD video format to save data, you can play on the player。
   Format need to spend an hour and a half hours。 DVD + R DVD + R is write once DVD + RW's variant, DVD + R and the staining method is very similar to DVD-R, DVD + R is therefore also compatible with part of the DVD-R。
   Features: DVD + R can be written into the data format CLV。 DVD + RW DVD + RW rewriting technology CD-RW based on the above, some available by the end of 2001。
   Philips, SONY, HP, Dell, Ricoh and Yamaha support DVD-RW, DVD + RW burner can read DVD-ROM and CD-ROM, can also read DVD-R and DVD-RW, but can not read DVD-RAM。
   In contrast, most of the DVD-ROM and DVD players can read DVD + RW。 DVD + RW burner to burn DVD + RW in addition to, but also can burn CD-R and CD-RW。
   DVD + RW the existing capacity of each side of 4。7GB, the early 1。0 versions, each side is only 2。8GB, and are not compatible with the majority of players and DVD-ROM。
   Characteristics: ease of use, but also increased the CD-ROM DVD-RW compatibility, that can be started from the recording format in the background, so a minute later to start recording data。
   DVD + RW recordable disc formats to support the two, namely, Sequential Video Acess CLV format, as well as the CLV format Random Acess。
   No longer support DVD-R and DVD-RW disc specifications DVD Multi / DVD Dual DVD Multi and DVD Dual in the above-mentioned specifications is derived from the product。
   DVD DUAL beyond the burner DVD + RW or DVD-RW recording the threshold of a single specification, can burn DVD + RW and DVD-RW disc DVD two specifications, and as a result of recording with the flexibility of chip design, Even after the royalty or as a result of two trends in the specifications resulting from changes in the design can be flexibly adjusted in order to avoid the duplication of resources and the development of a waste of time。
   DVD Multi features: integration of DVD-R/RW and DVD-RAM DVD Dual features: integrated DVD + R / RW and DVD-R/RW List of DVD recording technology Lossless link (lossless join) technology 缓存欠载running when burning (buffer under run) or body tremors (vibration) and other system problems, Lossless Link will be activated and temporarily stop burning, burning at the same time will break their own record。
   When the data flow back to normal when the last extension of the location of entry continue to burn。 Its recording of the gap between breakpoints and was controlled at less than 1 micron, sufficient to ensure the quality of recording。
   Buffer Underrun (end of rejection) technology Buffer Underrun end piece of waste burning technology, the full protection of the quality of disc recording, while cooling holes will be designed to facilitate the hot air exhaust, to avoid high temperature inside the machine and the machine itself or on CD adverse impact。
   CD-ROM not only the stability of its operation, but also to ensure a good quality recording。 Tilt control technology Tilt control is called "chi laser guided" technology, its role is to adjust the laser to read and write their own power, in order to protect the consistency of disc burning process。
   Under ideal circumstances, the disc spindle motor and the burner should remain vertical to 90 degrees。 The actual recording operation, as a result of their own choice of disc burning different materials, processes and other reasons, can cause burn to disk from the outside in different angle of inclination, which in turn leads to the disc surface conduction of laser power fluctuations have 。
   And equipped with laser guided technology Moses burner, you can operate under the disc, as well as the status of quality, intelligent adjustment of laser power, thus ensuring consistency throughout the recording process。
   Defect management technology Defect management system known as intelligent error correction technology, its role is a defective CD-ROM part of the effective detection, if it is found that the problem will be the point they recorded。
   Read and burn discs in the process, the recorder records automatically skip these regions, so as to ensure the quality of load, as well as burn。
   Even if inadvertently so consumers use less of the quality of the disc, there was no need for the disk or burn读不出to worry about poor performance。
   Quick Background Formatting technology quick format This is the DVD + RW burner unique technology, compared to DVD-RW burner to burn must be completed before the entire disc format (time 20-30 minutes), DVD + RW recorder can be fast background formatting functions to be placed in the recording disc burner, the disc automatically in the background of the rapid format, if the Add CD-ROM burner at the same time can also be started at the same time, do not have to wait until the whole complete disc format began to burn again。
   Mt。Rainier Technology In some CD-RW is also the addition of this technology, Mt。Rainier (drag and drop burning) is in the hard drive directly through the mouse drag operation does not require complex software to achieve the purpose of recording, so that work and the hard disk recorder as simple as copying files and user-friendly。
   Interface type Optical storage drives and drive interface is the physical link to the host system, it is the drive to the computer from the data transmission channels, different interface also determines the drive with the speed of data transmission systems。
   At present, optical storage products connected with the system interface of the type: ATA / ATAPI interface USB interface IEEE1394 interface SCSI interface Parallel interface The earliest use of the optical storage products are also a number of dedicated interfaces, such as Sony, Mitsumi, Panasonic and other drive makers, have been developed and drive the company-specific interface。
   Such interfaces are not compatible between each other, such as SONY is the 34-core interface, while the Panasonic is the core of the interface 40。
   Therefore, such a dedicated interface requires additional hardware support, such as random card attached to the driver。 In addition, some sound card like Sound Blaster, Pro Audio Spectrum are also integrated this kind of card-specific CD-ROM interface。
   As a result of poor compatibility, the current of such a drive has been extremely rare。 Installation Optical storage for the two types of external and internal, built-in is installed on the host computer itself, external interface is connected through an external host。
   DIY built-in market is the most common types of optical storage products, almost all production of optical storage manufacturers have built-in ATA / ATAPI interface products External optical storage products are mainly aimed at users who need to move the work, more emphasis on mobility, to be inferior in performance to the built-in optical drive。
   Its data transmission rate is subject to restrictions on the external interface。 And based on the demand for portability, optical storage products, external size, weight are subject to constraints in the domestic market, the performance of external optical storage products to well below the built-in; and performance in the professional market with the built-in basic and fairly, However, a significant discount and portability, and price is much higher than the built-in。
   Maximum speed DVD burner The market functions of DVD burner to burn the highest attainable speed of 16 speed, for 2 ~ 4 of the burn rate of speed per second data transfer capacity of 2。
  76M ~ 5。52MB, burn a DVD disc of 4。7GB takes about 15 to 27 minutes; and 8-speed to burn only need 7-8 minutes, only to burn a CD-R's a little slow, but taking into account the amount of data recording, 8-speed of write speed has reached a high level。
   DVD burning speed of DVD burner to buy the primary factor, if sufficient funds, as far as possible, choose the high-speed DVD burner DVD read speed of the largest DVD read speed is the largest optical storage products refers to read DVD-ROM discs, the drive can achieve maximum speed。
   The speed DVD-ROM speed is defined。 At present, DVD-ROM drives can read DVD maximum speed of 16X; DVD burner can achieve the maximum DVD read speed is 16X; currently Combo products in shopping malls in support of the largest DVD read speed 8 speed and 16 speed two。
   Maximum speed of DVD replication DVD replication is the speed of DVD burners in the corresponding specifications of the DVD burner to burn CD-ROM, stored on CD-ROM data, data erasure and its new data recorder to burn the maximum speed。
   Current standard of DVD burner to achieve the largest of the largest DVD replication rate of 4-speed, that is, per second of about 5。
  4MB / s speed DVD average seek time Average seek time is a measure of optical storage products, an important indicator refers to optical storage products to find a CD-ROM can be read at the data in the Regional Road, the average time spent, unit is ms average seek time is the purchase of optical storage One of the key parameters of products, a faster average seek time to provide higher data transmission speed。
   The speed of optical storage products has been improved, the lower the speed of data transmission problems are better resolved, but after the speed upgrade has brought a number of other new problems。
   High-speed rotating disc prone to vibration, noise, resulting in greater heat, which will shake it more difficult to position the laser head, is bound to lead to longer seek time。
   Increase in drive speed, the laser head of the drive mechanism and positioning system has been in development so as to protect at the same time improving the speed and reduce seek time。
   The first generation of single-speed CD-ROM average seek time for 400ms, and the latest speed of 40 ~ 56 optical storage products, seek time for 80 ~ 100ms, the speed has been greatly improved。
   Burners in general than the average seek time CD-ROM average seek time is longer, the shorter average seek time, representatives of optical storage can provide faster data transmission, better performance will show a continuous transmission。
   Buffer capacity Optical storage drives with an internal buffer or cache memory。 These buffers are the actual memory chips installed in the drive circuit board, which send data to the PC may be prepared prior to or even greater data storage segment。
   CD / DVD buffer size of a typical 128KB, but specific可大可小drive (usually better)。 Recordable CD or DVD drives usually have more than 2MB-4MB buffer capacity to prevent缓存欠载(buffer underrun) error, at the same time work can burn steady, constant write。
   In general, the faster the drive, there is more buffer memory to handle the higher transmission rate。 CD / DVD drive with a buffer or cache with many advantages。
   PC buffer can guarantee a fixed rate of receiving data。 When an application requests data from the drive, the data may be scattered at different places on CD-ROM。
   Because the drive is relatively slow access speed, read in the data would have to drive to the PC send data间隔性。 Buffer drives under the control of the software in advance and be prepared to read the contents of CD-ROM directory, thus speeding up the first data request。
   CD-ROM to read the rules of data is one of the first find in the cache, if not found in the cache to the CD-ROM only to find, high-capacity cache data can be read in advance the more practical application in the CD-ROM , DVD-ROM, such as read operation, read the opportunity to repeat the information is relatively small, most of the CD more often is a large number of documents to read, so in the CD-ROM, DVD-ROM the importance of drive cache is not reflected, so the use of such products are mostly smaller cache capacity。
   CD-ROM There are 128KB, 256KB, 512KB several; and DVD There are 128KB, 256KB, 512KB, only individual external DVD drive capacity using a larger cache。
   COMMBO burner or in the products, the cache becomes very important。 CD burning, the system will need to pre-burn data to a cache read, and then read the data from the cache to burn, and burn the data cache is a bridge between the disk。
   System in the transmission of data to the cache, the inevitable will happen pause transmission, such as a large number of small capacity in the recording file, the hard drive read speed is likely to not keep up the speed to burn, it will result in relief keep the data out of proportion to the input and output, if this state to continue for some time, it will lead to the data cache the full output, and the lack of input,缓存欠载at this time will result in errors, which would lead to failed to burn CD-ROM。
   Burner and therefore products COMMBO capacity will be larger cache capacity, and then carved with the anti-death technology, we will be able to set the probability of a bad moment to a minimum。
   At the same time, the coordination of data cache can speed data transmission to ensure stability and reliability。 Burner products generally have 2MB, 4MB, 8MB, COMBO products generally have 2MB, 4MB, 8MB of cache capacity, subject to the restrictions on manufacturing costs, the cache can not create enough。
   However, an appropriate amount of buffer capacity of optical storage, or choose one of the keys need to be considered。 Write mode The production of different types of CD-ROM into the methods used are not the same, the current into the more commonly used methods are as follows: Time to write disk (Disk At Once) Way to write a disk (Disk At Once), generally abbreviated as DAO。
   The first to write a single disk write is the way to guide the district, data track, as well as export and they are one-time write, after writing a CD-ROM on the closure, even if this is not written into the disk of the recording can not write into the other data。
   When the boot sector written to the CD-ROM, there is no guidance in the area marked out for the next available address, so the CD-ROM will be regarded as closed, and then will not be able to write more data。
   This mode is mainly used to write CD-ROM copy, the first complete recording of the entire CD-ROM。 Its characteristics are copied from CD-ROM can source exactly the same disk。
   DAO can be easily written for the music CD, mixed, or specific types of data such as CD-ROM gap between tracks on CD-ROM replication, and to ensure that the data structures are identical with the gap length。
   It is worth mentioning that, as the DAO into the way the entire CD as a section to deal with, some small errors may lead to total loss the whole CD, so its data transmission, stability and performance drives higher requirements。
   Write track (Track At Once) Into the way the track (Track At Once), generally abbreviated as TAO, and the one-time write DAO different, TAO is a way to write many times。
   TAO is based on the write track for the units the way, in a write process to write all the tracks one by one, if more than one track, the track in the last write before the end of a track to write, and write a track do not shut down after the end of the section。
   Because it is used to burn all tracks in this way, that is to burn the end of the。