Aargil Video

PAL is the acronym for Phase Alternating Line in television terminology. It is used to describe a color encoding system that is used in broadcast television systems in most parts of the world. It was Walter Bruch at Telefunken in Germany who had developed PAL, and it was in 1963 that the format was first unveiled. The first broadcasts were in 1967, in United Kingdom and Germany.

PAL TV systems are 625-line/50 Hz television systems and are different from the 525-line/60Hz NTSC television systems. PAL TV systems are predominant in Europe while the NTSC systems are found mostly in North America, Central America and Japan. DVDs that can be played on these systems are accordingly labeled as 'PAL' or 'NTSC'. However European discs usually don't have PAL composite color while NTSC defines the video line and frame format by contrast.

The PAL TV systems have greater resolution than NTSC and are more accepted because of its higher quality. The NTSC systems have tint controls that correct color manually; and if not corrected properly, colors turn out to be faulty. In the case of PAL TV systems, hue errors are automatically removed with the utilization of phase alternation of color signals it receives. This is why there is no need of any tint control with PAL TV systems.

With the help of a 1H delay line that produces lower saturation, the chrominance phase errors that may occur in the PAL system are cancelled out. This is in turn very much less noticeable to the eye than the hue errors you find in NTSC systems.

There is a small drawback in PAL TV systems where the alternation of color information through Hanover bars can at times lead to picture grain on pictures having extreme phase errors. Sometimes even the mis-alignment of decoder circuits or the use of simplified decoders of early designs in the PAL TV system may lead to picture on grain on pictures.

However such extreme phase shifts do not occur much. The effect is usually observed when the transmission path is poor, if the terrain is an unfavorable one or in typically built up areas. It has been noted that the effects are more noticeable on UHF signals than on VHF signals. This is because VHF signals are generally more robust.

The greatest advantage of the PAL TV system over the NTSC system is that it avoids the NTSC system's sensitivity to phase changes through minor modifications where high color fidelity is achieved. With the help of a delay line and two adders, the PAL decoder adds color signals of successive lines while canceling out phase errors. The delay line here works as a line storage device.

Today, the PAL TV system is the most common and prevalent television system found in more than 65 countries because of it excellent color stability. There are different brands of PAL TV systems available today; it is up to you to choose the best brand and model you want depending on your budget and your entertainment requirements.

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Television systems across the world are different. The two most popular formats are NTSC, used in North America and beyond (National Television System Committee) and PAL, used in Europe (Phase Alternating Line). Since you record a signal on a camcorder that ultimately is supposed to be watched on a television, camcorder manufacturers make different models of the same basic unit to support these different television formats. Not surprisingly, video shot on one system won't work on another system. This doesn't help when you want to show video of the kids to your family overseas.

(For more information on video standards, check out the National Center for Supercomputing Applications World Wide Television Guide.)

There are ways around this problem. Before I get to that however, I want to discuss a bit about how the formats are different, and the same.

As far as camcorders are concerned, NTSC video is characterized by a frame size of 720x480, and produces images at a rate of around 30 frames per second. PAL video is slightly different in that there is a bit more image quality - the frame size is 720x576 - but it only produces 25 frames per second.

When a miniDV camcorder sends data out from its DV port (known similarly as firewire, i.Link and IEEE1394), it doesn't matter what format the video was shot in. As far as the computer is concerned, it's just a bunch of ones and zeroes. In fact, if you do some basic math, you see that NTSC and PAL have a common bandwidth that makes data transmission work:

NTSC: 720 x 480 x 30 = 10,368,000

PAL: 720 x 576 x 25 = 10,368,000

So, regardless of whether it's NTSC or PAL data, the computer knows what to expect. And when you capture it to the computer, most editing programs will be able to work with the video regardless of the format. However, that's where the fun begins.

Conversion: the quick and dirty way Editing programs allow you to change the frame size easily enough, and there are also options for changing the frame rate. The frame size is easy, but the way most programs change the frame rate is to just add or remove a proportionate number of frames to make up the difference. For example, to change from 30 frames per second to 25 frames per second, you have to remove 5 frames every second. The simple way of doing this is to just take out every sixth frame (30/5=6). But what this actually ends up doing is giving your video a 'skip' every sixth of a second (which in practice, is pretty disorienting). If you can live with that, then converting from NTSC to PAL is as simple as that. Of course you also have to expand your frame size from 480 pixels to 576 pixels of height, either by adding 96 pixels of blank space or stretching your image by 20% vertically. Either way, you're going to have to recompress each frame of your video, so you may be letting it run overnight.

Converting from PAL to NTSC is the same thing only in reverse. You have to compress your image by 20% vertically, or crop 96 pixels; and, you have to add five frames to every second. This will make your video seem to 'pause' every sixth of a second, for 1/30th of a second.

Alternately, you could just change the frame rate of the actual video from standard to the other. For example, changing from NTSC to PAL, you would adjust the frame rate to 25 fps. This has the operative effect of speeding up the video by 4%, which is going to make everyone talk a little faster. The easiest way would be to use a program like VirtualDub, but unfortunately it doesn't support miniDV video, so you'll have to do some digging on your own there.

Conversion: the more intensive (and possibly expensive) way The better way of converting from NTSC to PAL is to use a program like After Effects to 'blend' frames to match the new frame rate. This is a very computationally expensive process and is definitely an overnight thing. You still have to crop or stretch the frame size to fit, but the results will be much more pleasing to the eye. There are even plug-ins which are designed to specifically address this problem.

If you're interested enough in standards conversion to lay down $145 on a piece of software, a company called DVFilm offers a product called Atlantis which apparently does this conversion with ease. Though I can't speak to the results, the testimonials are pretty convincing. For more information check out DVFilm Atlantis.

The last and most robust solution for NTSC-PAL conversion is a multi-format VCR. These VCRs will convert a signal between two standards, allowing you to play PAL on one and record NTSC on the other (or vice versa). Again, these models can be quite expensive, so for a one-time-only experience it may be worth your while just to track down a store which will do it for you.

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Although VHS video format is the same throughout the World, the video standard or electronic signal that is recorded on the cassette varies from country to country. The two most common video standards used are NTSC and PAL.

NTSC is the video system or standard used in North America and most of South America. In NTSC, 30 frames are transmitted each second. Each frame is made up of 525 individual scan lines.

PAL is the predominant video system or standard mostly used overseas. In PAL, 25 frames are transmitted each second. Each frame is made up of 625 individual scan lines.

NOTE: If you want VHS PAL standard and it is stated on the product page as available in PAL, type "Want in PAL Standard" in the comments field at the bottom of the ordering page.