Glossary

Audio CD

Audio CD contains digital audio tracks recorded in the compact Disc-Digital Audio format. Audio CDs store up to 74 minutes of music and can contain up to 99 tracks.  Audio CDs can be played back from a CD player or from a CD-ROM drive through speakers or headphones.

Audio on CD-ROM

Audio can also be placed in the form of wave files on a CD-ROM. Wave is a standard DOS/windows format for audio files and is essentially identical in quality to the audio CDs. If the audio / music has to be manipulated in the computer using many of the audio processing software available, then audio in the form of wave file is more useful.

CD-R and CD-RW Recordable (CD-R) and ReWritable (CD-RW) CDs. All CDs produced by CVMS are CD-R discs.

CD-ROM

CD-ROM, (Compact Disc - Read Only Memory), is the standard CD for CD-ROM drives used in personal computers. A CD-ROM can hold a mixture of data/programs for the computer, images, audio and video. The specifications for a CD-ROM were first defined in Yellow Book .

There are two basic file systems for CD ROM.
Juliet     - for Microsoft Windows and DOS
IS09600 - for multiple operating systems such as DOS, Macintosh, OS/2, Windows and Unix.  

Digital Cameras & 3-chip Digital Cameras 

Digital cameras produce far superior pictures because they do not compress as much as analogue cameras. Most domestic cameras use a single imaging chip as optical sensor. A professional camera would use 3 imaging chips ( for the 3 primary colours) to produce much crisper picture.

Digital Edit Suite

A digital edit suite allows the videographer to transfer all the footage to a hard disk before editing. The video is prepared on the computer, adding titles and music. The video or the movie can be changed quite easily whilst it is still on the computer. The editing time is reduced because the editor does not have to wind and rewind all the tapes to find the bit that is required. The master tape is not damaged because it is only used once or twice for editing. The final movie is then transferred to a digital tape. There is virtually no loss in quality. 

Digital Standards Converter

A digital Standards converter changes the format of video from one format in to another. The process is very complex because this may involve changing the speed of the video (25 frames per second in PAL and 30 frames per second in NTSC), changing number of lines that defines the picture (625 lines in PAL and 525 lines in NTSC), and /or changing the way colour information is added to the tape. A Digital Standards Converter stores one frame of picture at a time in its memory, changes it as required and then outputs it to the tape. This is the best way of achieving standards conversion.

DV (Standard)

Standard Digital Video tape. Very few camcorders use this size of tape although it does give running times of up to 3hours.

DVC

Digital Video Tape. This tape standard was introduced in late 1995 for the new digital camcorders. There are two tape sizes available. Standard DV and mini DV. Most of the domestic camcorders on the market use mini DV tape.

DVCAM

This is an improved version of DV format tape developed by Sony. Improved tape formulation gives near broadcast quality pictures. 

DV (mini)

All digital video cameras in the domestic range - except one Sony model - use mini DV tapes.

DVD DVD stands for digital video disc or digital versatile disc.
There are important differences between the physical formats of  DVD-ROM, DVD-R, DVD+R, DVD-RW and DVD+RW .and the application formats of DVD-Video and DVD-Audio.
DVD-R DVD-R is like a CD-R, and is compatible with most 2nd generation DVD players. The capacity of DVD-R is 4.7 billion bytes. Matching the 4.7G capacity of DVD-ROM was crucial for desktop DVD production.

CVMS uses this format for supplying video. For a compatibility list  Click here . If your player is not listed visit www.vcdhelper.com

DVD Player

Digital Versatile Disc or Digital Video Disc Player.
Some DVD players are fitted with dual lasers and hence are capable of playing CD-R and CD-RW types of audio and video CDs. CVMS uses CD-R technology to produce video CDs. A list of compatible DVD players is available at www.vcdhelp.com/dvdplayers.htm or call CVMS for details.  

Format Conversions

There are six common domestic video cassette formats. video 8, video hi8, VHS C, S-VHS, S-VHS C and DV. Within DV formats there are two domestic formats and two professional formats. There are further broadcast formats using DV variants. The domestic format uses standard DV or mini DV. The latter is the most common in use. CVMS will convert from any of the above formats.   

hi-fi sound tracks

Modern Video Cassette Recorders (VCRs) are equipped with hi-fi sound tracks and / or linear sound tracks. The linear track is recorded on the edge of the video tape and has a frequency response in the region of 60Hz to 8KHz and this is slightly better than listening to AM (or MF) radio station. The hi-fi track is embedded below the video signal and has a near-CD quality sound with a frequency response of 20Hz - 20KHz. CVMS use modern VCRs with hi-fi tracks for all duplication, format conversion and standards conversion. 

High Band

S-VHS, S-VHS C and Hi8 format are high band formats. They use improved formulation tapes to deliver higher resolution and better picture.

Horizontal Resolution

This is a measure of picture quality indicating the amount picture detail present. The measurement is specified in number of lines. The measurement indicates that if a number of vertical lines were shown on a TV screen, Horizontal Resolution will indicate how many lines can be seen.
VHS and video 8 format will show 240 - 260 lines. High band format such as S-VHS, S-VHS C and Hi8 format will show about 400 lines. Domestic digital formats will show about 500 lines and broadcast quality system will show 700 lines.

Media Player

A Windows utility which enables playing of various video formats including MPEG1.

MESECAM

This is variant of SECAM TV system and is mainly used in Middle East.

mini DV

All digital video cameras in the domestic range - except one Sony model - use mini DV tapes.

MPEG1

Motion Picture Expert Group have defined compression formats video and sound.  MPEG1 standard compresses video and audio to 1/30th of original size  without sacrificing too much quality. This allows about 60 minutes of video to be squeezed on to one CD.

The MPEG1 format in PAL has the following characteristics:
Picture size:        352 x 288 pixels
Sound sampling:   44.1 KHz
Video Bit rate:      1150 KBits per second
Audio Bit Rate:      224 KBits per second
CD-ROM Speed:    4 speed or greater.

MPEG2

Motion Picture Expert Group have defined compression formats video and sound.  MPEG2 is the standard used by digital and terrestrial satellite broadcasters. The Digital Versatile Disc (DVD) also uses this type of compression. Although the  picture quality is the best that is available, the standard is versatile enough to allow broadcasters and DVD manufacturers to reduce the picture quality to suite the market.

NTSC

National Television Standards Committee. This TV standard is used in Japan, North America and most (but not all ) of South America. 

PAL

Phase Alternate Line. This standard is used in much of Europe, United Kingdom, Australia, India, East Africa and China. There are variations in this standard which affects the way TV receives its signal but these variations do not affect video tapes. 

PAL - N

A variant of PAL system is used in some parts of South America. PAL recorded tapes are NOT compatible with PAL-N.

Photos on CD

Photos are placed on CD as graphic files. The quality will be dependent on the size of the images. We normally recommend JPEG format. The images can then be manipulated using graphics software or printed using colour printers. Please note that this not the same as PHOTO CD. This CD-ROM XA format is used by Kodak.

Professional quality tapes

There are tapes and there are professional grade tapes. When the copy is precious, using a professional grade tape ensures that the cassette shell is the best that is available - premium grade. The tape is wound by the manufacturer and the tape is of high grade. CVMS only use branded professional tapes for duplication, Standard conversion and format conversion.

SECAM

SECAM (Sequential Couleur à Mëmoire ) is used in France, West Africa, and Ex Soviet Union.

Standards Converter

This system changes the format of video from one format in to another. The process is very complex because the process may involve changing the speed of the video (25 frames per second in PAL and 30 frames per second in NTSC), changing number of lines that defines the picture (625 lines in PAL and 525 lines in NTSC), and /or changing the way colour information is added to the tape. There are various ways of achieving this but the best way to do this is to use a Digital Standards Converter.

S-VHS and S-VHS C

Super VHS. This is high band - and better quality - version of VHS format. The tape size is the same but tape formulation is improved to give better horizontal resolution. S-VHS tapes do not work in VHS machines.

Time base correction

A VHS or video 8 VCR compresses the video information so that this can be transferred to tape. The tape records control pulses which tells the VCR were the information should be. During the recording process these pulses can get degraded causing jitter on the picture and degradation of vertical definition within the picture. A good quality digital Time base Corrector replaces these pulses with new ones thereby improving the quality of the copy. 

TV - Standards

There are three TV standards in use world wide. PAL, NTSC and SECAM. Each standard has its own variants such as PAL and PAL-N, SECAM and MESECAM, NTSC-M and NTSC-J.

VHS

Video Home System or Vertical Helical Scanning. This is the most common domestic video tape format - at present.

VHS-C

A compact version of VHS. This uses same size of tape but in a smaller cassette. VHS-C is normally used in camcorders. To play the VHS-C tape in a normal VHS VCR, an adaptor is used.

Video 8

Tape standard developed by Sony. These tapes only play in special 8mm VCRs or the 8mm camcorder.

Video Hi8

A high-band version of video 8. A video Hi8 tape will not play in a video 8 player / camcorder whereas a video 8 tape will play and record in a Hi8 player / camcorder.

Video CD and Video on CD

Video and stereo sound are compressed together using MPEG1 format and then recorded on a CD. A video CD will play in a Video CD player if it is recorded using special file structure (ISO9660) which defines configuration of each track. If the video is to be played on computer screen then you would require video on CD. This comprises of standard  video file (*.mpg). This can be used with the media player supplied with Windows 95 to view the video.
A Video CD renames the file from *.mpg to *.dat. This file is located in a directory called MPEGAV. This video file may be played using media player but the media player needs to know that this is a video file.

Video CD Player

A Video CD player (VCD Player) is equipped with MPEG1 decoder and has outputs to connect to the TV. A special file structure is created on the CD to enable VCD Player to decode the video and play it on the domestic TV.
A VCD will work in DVD players equipped with dual lasers. Call CVMS to find out if your DVD player will play video CDs.

World TV standards

There are three TV standards in use world wide. PAL, NTSC and SECAM. Each standard has its own variants such as PAL and PAL-N, SECAM and MESECAM, NTSC-M and NTSC-J.

 

 
Last Modified: 10-Apr-2005