NTSC Vs. PAL


NTSC and PAL are two different video standards, that decide how a video signal is displayed or rendered on analog video systems. Due to incompatibility of these standards, a DVD encoded in NTSC format, won't be rendered properly by an analog video system that is built for a PAL format. That is why, American NTSC format videos won't be rendered properly on European television sets and vice versa.

One may wonder why does the difference between two analog video formats like NTSC and PAL matter in this age of digital TV and HDTV. There is one prime reason for this, which is the following. Even though the signals are digitally modulated, their rendering on television sets and computer screens is still analog! So, frame rate and pixels displayed per second, which are defined by the NTSC and PAL standards, still make a difference.

Any video is actually a display of rapidly changing series of still images displayed in succession. The rate of change of each picture frame is so high, that our eyes do not notice the discontinuity between the images. On a TV screen, there are two ways in which pictures are rendered. One is the interlacing method and other is a progressive method.

In both methods, every frame is divided into lines. In the interlacing method, alternate set of odd and even lines are displayed in succession, while in the progressive method, each line is rendered on screen numerically. More the lines of display on screen, more is the resolution and clarity of the moving picture. Two important parameters are the frame rate (still images displayed per second) and the resolution (number of lines in each frame). After this brief background, let me begin with the NTSC format vs. PAL format comparison.

Fundamental Difference Between NTSC and PAL

NTSC stands for the 'National Television System Committee', which was instrumental in developing this analog video format as a TV broadcasting format. First developed in 1941 in USA, it was modified in 1953 for color television. In 2009, it was replaced by the ATSC (Advanced Television Systems Committee) format as the default standard for over the air television signal transmission.

PAL (Phase Alternating Line) was introduced as an analog television encoding system in 1963 and invented by Walter Bruch at Telefunken, a German television company. It is used throughout most of Europe and Asia as the default analog television video standard. Let us see the NTSC/PAL difference according to region of usage, frame rate and resolution.

NTSC Vs. PAL: Region
NTSC as a format for transmission and display of video images is used in Canada, Japan, Mexico, Korea, Peru, Panama, Nicaragua, Panama, Philippines, Cuba and until very recently, USA. Compared to NTSC, PAL has a wider worldwide acceptance. It is used in Germany, United Kingdom, Switzerland, Australia, India, Denmark, Finland, Brazil, Indonesia, China and many other countries around the world.

Difference in Frame Rate
Due to the frequency of alternating current delivered in United States of America being 60 Hz, NTSC based signals are rendered at a rate of 60 fields per second. Due to the interlacing nature of rendering method on a television, this means that an NTSC based television has a frame rate of 30 per second.

On the other hand, the countries which have electrical power delivered at 50 Hz, have a PAL frame rate of only 25 frames per second. This is because, the moving picture in the PAL format is delivered at the rate of fifty fields per second.

Difference in Resolution
The picture quality is dependent on the resolution and frame rate. Resolution is quantified in terms of number of lines delivered in each frame. A PAL based system, delivers 625 lines of resolution, compared to only 525 delivered by NTSC. Color quality is much better in PAL based systems as compared to NTSC.

Hope this NTSC Vs. PAL comparison has left no doubts in your mind, about how these two formats are different. Be aware that an NTSC format DVD won't play on a PAL compatible DVD player and vice versa because of NTSC/PAL difference. Some companies offer the facility for interconversion between NTSC and PAL, but it can be time-consuming. Just see to it that you take care of these analog video format differences, when sending video files to European or Asian countries as they use PAL format. When purchasing DVDs, do not forget to check the analog video encoding format it has and see to it that your DVD player and television are compatible with it.

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