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Video standards and technical information
- NTSC - National Television Standards Committee
- Introduced in 1954 as the first set of standard protocols for television.
It is used throughout the USA, Canada, Japan and elsewhere.
NTSC has 525 lines displayed at 30 frames per second.
It has a lower resolution than PAL or SECAM
but a faster frame rate which reduces flicker.
- Technical information:
- Line Frequency - 15.734 kHz
Scanning Lines - 525
Field Frequency - 60 Hz
Color Signal Modulation System Suppressed Quadralure Modulation System
Color Signal Frequency - 3.579545 MHz
Burst Signal Phase settled
Video Bandwidth - 4.2 mHz
Sound Carrier - 4.5 mHz
- PAL - Phase Alternating Line
- Developed by Walter Bruch at Telefunken (Germany)
and used in much as western Europe, Asia, throughout the Pacific and southern Africa.
PAL has a higher resolution than NTSC with 625 lines, but it runs
at 25 frames per second.
- Technical information:
Line Frequency 15.625 kHz (Pal M is 15.750)
Scanning Lines - 625 (Pal M is 525)
Field Frequency - 50 Hz
Color Signal Modulation System Suppressed Quadralure Modulation System
Color Signal Frequency - 4.433619 MHz
Burst Signal Inversion by 1H
Video bandwidth - Pal B,G,H:5.0 MHz; I:5.5; D:6.0; N,M:4.2
Sound Carrier - Pal B,G,H:5.5 MHz; I:6.0; D:6.6; N,M:4.5
- Variations:
There are two variations that have been developed: PAL-M and PAL-N.
The only country using this standard is Brazil.
The main differences between PAL and PAL M is a lower resolution (525 lines instead of 625)
and a higher frame count (30 frames per second at 60Hz versus 25 frames per second at 50Hz).
PAL M grew out of NTSC as an attempt to correct the color problems of NTSC.
PAL-N is another variation that is only used in Argentina and Uruguay. Differences here
include the sub-carrier frequency.
- SECAM - Sequential Couleur Avec Memoire
- SECAM was developed in France (predominantly a political decision) out of PAL
and is used in France and territories, C.I.S., much of Eastern Europe, the Middle East and northern Africa.
This system uses the same resolution of PAL, 625 lines, and frame rate,
25 per second, but it is not compatible to PAL.
- Technical information:
Line Frequency - 15.625 kHz
Scanning Lines - 625
Field Frequency - 50 Hz
Color Signal Modulation System FM Conversion System
Color Signal Frequency - 4.40625 MHz/4.250 MHz
Burst Signal Phase settled
Video bandwidth - B,G,H: 5.0 MHz; D,K,K1,L: 6.0 MHz
Sound Carrier - B,G,H: 5.5 MHz; D,K,K1,L: 6.5 MHz
- Variations:
There are three varieties of SECAM: French SECAM used in France and its (former) territories,
MESECAM which is used primarily in the Middle East and North Africa and
D-SECAM which is used primarily in the C.I.S. and the former Eastern Block
countries.
- HDTV - High Definition Television
- HDTV is part of Advanced TV, or ATV. This is a new digital television
technology that provides picture quality similar to 35 mm.
movies with sound quality similar to that on today's compact disc. The HDTV
technology exists and some television stations have begun transmitting to users
on limited channels. HDTV uses digital rather than analog signal transmission,
utilizing the MPEG-2 file format and compression standard.
HDTV is also a standard that is becoming available on cable and satellite TV.
- For more information of HDTV, visit www.hdtv.net.
For additional information, please visit the following sites:
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