What is LD
LD is the abbreviation of English Laser Disc, translated into Chinese is "laser disk", because it is mainly used to record audio-visual information, so it is called "laser visible", and sometimes directly referred to as "laser shadow disc" according to pronunciation. The diameter of the LD is generally
20cm
or
30cm
The image is clear, the sound quality is excellent, and the "home theater", which is usually said, often uses the LD player as a playing device, of course, the plain disk is LD.
What is CD
The CD is the abbreviation of English Compact Disc, meaning laser record, its diameter is
12
cm
. The laser visible disk (LD) and the laser record (CD) are usually referred to as a disc. The main difference between them is that the image portion of the laser visible disk is recorded in analog manner, and its sound portion is recorded in analog or analog and digital mixing; and the sound and images of the CD class are recorded in digital. On the action, the CD is dominated by recording and playback, while LD is based on record and playback image.
What is VCD?
VCD is the abbreviation of English video Compact, translated into Chinese is "video compression disc", in fact, "Video CD". It is the same size as the ordinary CD, and there is no difference in structure. It is only the film and television show, so it is commonly known as "DVD", but it is also known as the LD video used by the laser disc player, so it is also known as "small video". Its audio and video playback quality is better than the video, but it is slightly more poor than the large movie. The VCD disc can play directly on the VCD machine or play in a computer that is configured.
What is SVCD
SVCD (Super VCD) is also called a super VCD, which is a data structure using CD recording format and CD-ROM / XA. Press MPEG2 variable code string encoding (VBR) record activity image and its sound, image level sharpness reaches 350 lines The quality matches the current analog TV display level (350-400 line). Super VCD DOP can play on super VCD on-screen, CD-ROM / XA, and other hardware and software work platforms, resulting in full screen high-resolution high quality activity images, as well as high quality dual stereo or four-way audio. The super VCD disc also selects still images containing sounds, and controls the playback table for static and active image presets, and implements e-book functions. The super VCD drive is compatible with the VCD disc.
What is DVD?
The abbreviation of DIGITAL VERSATILE DISK is the latest standard for disc storage devices, which is equivalent to the general disc size, but can accommodate more information. DVD is developed by Toshiba and Philips, which is expected to introduce new standards for growth rate multimedia and interactive application systems. For the PC application level, the DVD uses the difference between the CD-ROM, mainly in the special product of its storage capacity. Double-sided double storage capacity can be as high as 17 GB, while single-sided double-layer can also store 8 GB of information. 8.4 GIG ON A CD-R Which Will Only Be Single Layer But Could Be Double OR Single Sided. PC Plays DVD-Audio and DVD-Video CDs. The new ROM drive, ie DVD-ROM will introduce new disc formats for the market.
Progress in digital audiovisual fields can be found by the development of DVD, so that multimedia applications do not limit due to lack of storage space. For example, the audio and video compression technology of the MPEG-2 standard can be used to process static images such as scan pictures and dynamic images. This compression allows you to store more information than traditional hard drives, such as single-layer single-sided DVD can accommodate film materials for two hours and thirteentals. Some DVD-ROM optical drive build MPEG-2 processing chips, some of which are directly attached to the PC system. HDVD and WDVD are new "DVDs", and their carriers are D5, all made in accordance with DVD production standards.
Different points are summarized as:
1, HDVD mainly over TV dramas, video coding is MPEG1, the track is unlicensed, the subtitles are unlikely, can be seen as a VCD with DVD! Features is a D5, the store is long, about 450 minutes!
2, 2, WDVD mainly distributed DVD movies, video coding is MPEG2, track, subtitle optional, to sacrifice image quality to get high compression ratio, and store DVD movies more than 200 minutes!
3, WDVD is made entirely in the production of DVD, and the video uses low-rate MPEG2 encoding, audio also uses Dolby AC-3 5.1 track. Several films made a few titles. When they start playing, there is a menu for choice. Each movie has one or more tracks, each movie has multiple subtitles optional, if the image quality is thrown, and There is no difference between ordinary DVD!
What is DVCD?
At present, there is a "DVCD" on the market. DVCD can be put 100 minutes. We think it is "high-density CD format", double the track density of the disc, does not change the laser parameters, so the perfect compatibility, DVCD appearance Brought a fatal impact to the DVD, because DVD changed the laser parameters, it is well known that CDROM cannot read the DVD disc, and the DVCD (Double VCD) has the same physical characteristics like VCD, and ordinary CDROM can read normally, but some CD-R optical drive exceptions; because the optical drive is automatically positioned with a laser, it is doubled, and the ordinary CDROM optical drive can still look properly and locate the track position, after the positioning track position, because DVCD does not change the laser parameters, so The normal CDROM drive can read data. Some CD-R optical drive exceptions are due to burning needs to use physical methods to secure the interval between the tracks to burn
650M
Data, so it cannot automatically locate the track position, so the DVCD cannot be read.
"High Degree CD Format" like DVCD can be applied to a normal data disc, as long as there is a CD-R burning optical drive that can be recorded into 1.2GB, it can make "high density CD format". We estimate that this CD-R burning optical drive can be bought from the market. In this way, DVD-ROM has no market. The appearance of DVCD is just just because SVCD needs to use a 4-piece disc that can accommodate it. It is enough to use the "high-density CD format" DSVCD. In the future, three "high-density CDs" can put down a full D1 resolution (720x480) movie, and the DVD has no advantage. This full D1 resolution can be played using a super VCD machine that is currently selling. This full range of compatible revolutionary innovation is the benefit of the VCD industry to rely on new steps.
However, the logical characteristics of the ordinary disc limits the further improvement of the "high-density CD format" capacity, because the original CD is 74 minutes of capacity: 74x60x75x2048 / 1024/1024 =
650M
Because the CD uses two BCD code to indicate the track sector address, the "high-density CD format" capacity can only be 100 minutes, that is, the data disc capacity is: 100x60x75x2048 / 1024/1024 = 879m
, The capacity of one sector is 2352 when storing VCD, that is, the maximum capacity of DVCD is: 100x60x75x2352/1024 / 1024 =
1009M
=
1.009g
Unless the CDROM driver is changed, use a 16-en-generated sector address representation method, in order to be compatible, use mode 3, maximum can be 256X60x75x2352 / 1024/1024 =
3273M
=
3.2g
. However, the reduced rail spacing can reach 3 times, 740mx3 =
2.2g
So to achieve
2G
The above, the new logic characteristics must be adopted 3 sectors. This is the limit of ordinary optical drive! The address of the mode 3 sector is indicated by a 16-based indication rather than the BCD code. 100 minutes of "high-density CD format" can be stored directly from 100 minutes without compressing CD music. If you only put 15 songs, you can support 5.1 surround sound without compress music, or 15 24-bit 48K high quality music. In short, "High Ministry CD Format" will bring new fun to life.
What is HDCD
High Definition Compact Disc (High Resolution CD) Abbreviation - An encoding system that improves CD sound quality, compatible with traditional CDs, but you need to play back on a CD machine with HDCD decoding or external HDCD decoder to improve effect.
