I bet a lot of people have heard terms like PAL, SECAM and NTSC. TVs and TV tuners in the process of tuning channels, often sin with questions about choosing one of them. The situation is aggravated when, in addition, it offers several subspecies of any of the three formats to choose from. And what to choose? And most importantly, how do all these formats differ from each other? In all this we will now understand.

There are three systems in the world analog color television - NTSC, PAL and SECAM, in many ways similar, and at the same time, differing in a number of parameters. This situation often requires the use of special decoders to convert video from one standard to another.

A television picture consists of lines (lines) displayed sequentially on the screen. This imaging method is called line scan, and the cycle of a complete change of the image (frame) - frame scan... The more lines on the screen, the better the vertical clarity of the image, and the higher frame rate eliminates the possible effect of flickering.

The figure shows the predominant use of color TV standards by region.

Basic parameters of TV signals

Due to the limited bandwidth of communication channels, each frame in all TV standards is transmitted in two receptions, or, as they say, consists of two fields. Initially (in the first field) even lines are displayed, then odd ones. Such scanning is called interlaced and, unlike horizontal, it somewhat degrades the image quality, but allows you to fit the TV signal into the standard bandwidth of communication channels.

The frequency spectrum of the full color TV signal is shown in the figure, from which it can be seen that the TV signal consists of luminance, color and sound signalstransmitted over communication channels using separate carrier frequencies. The main differences between the standards are in the way of color coding based on modulation of the carrier frequency of the color signal.

When displaying the received TV signal, the color component is superimposed on the luminance component. Therefore, when using equipment that does not support this or that standard, it is usually possible to obtain at least black and white picture... The audio carrier frequency can be different even in variants of the same standard, which is sometimes the reason for the lack of sound during normal video playback.

NTSC

This color television standard ( NTSC) developed in the USA. The first version appeared back in 1941, and regular TV broadcasts began in 1954. NTSCthe largest, at that time, electronic companies that were members of the national committee on television systems (eng. National Television System Committee (NTSC)). The current standard NTSCused in most of the American continent as well as in Japan, South Korea, in Taiwan and the Philippines.

Two options are widely used NTSC, denoted by the letter indices M and N. Historically, the first was, and is now the most common variant, NTSC M. Then came NTSC N (sometimes called PAL N), today it is used in some countries in South America. True, NTSC J also works in Japan, but this option differs slightly from the main one - NTSC M.

Main characteristics of the NTSC format

The horizontal scan rate for NTSC M is 525 lines per screen, the frame rate is 30. The video signal bandwidth is 4.2 MHz. NTSC N uses slightly more lines at 625 and a lower frame rate of 25 Hz.

System based NTSC allows to provide high quality color images, but imposes very strict requirements on the receiving and transmitting equipment. Due to the peculiarities of the formation of signals of this format, during decoding, it is not always possible to completely separate the signal into separate components, therefore, color signals are mixed with luminance. And, depending on the brightness of the image area, it can slightly change its color tone.

Phase distortions of the signal, which sometimes occur during transmission, also contribute to a not entirely natural transmission of color tone, and amplitude-frequency distortions cause a change in color saturation.

PAL

Standard PAL (eng. Phase Alternation Line) was first used in 1967 in Germany and Great Britain. Broadcasting in these countries began in slightly different versions, of which there are now even more. PAL is widely used in most countries in Western Europe, Africa, Asia, Australia and New Zealand.

In fact, PAL is an advanced NTSC system in which the sensitivity of the transmitted signal to phase distortion is eliminated by changing the modulation method of the color carrier frequency. True, this led to some deterioration in clarity, which is partially offset (in some versions of the standard) by the increased number of lines.

The PAL standard has the largest number of used varieties.

SECAM

Standard SECAM(French. Sequential Couleur Avec Memoire) - Sequential color transfer with memory was developed in France. Regular broadcasting with its use began in 1967, in France and the USSR. IN SECAM 625 lines are used at 25 frames, or 50 fields per second. Now SECAM used in France and some countries of Europe, some countries of the former CCCP and Africa.

The peculiarity of the system is that color-difference signals are transmitted by means of frequency modulation. Whereas PAL and NTSC use quadrature amplitude modulation. Frequency modulation, as well as alternate (through a line) transmission of two color signals made it possible to get rid of excessive sensitivity to distortion, but slightly worsened the clarity, which, however, in the reception conditions terrestrial television not always fundamental and most noticeable in cable systems. SECAM allows to achieve more natural color reproduction due to improved separation of color signals from luminance.

For recording on magnetic tape, a variation of the standard was used - MESECAM, in which the subcarriers of the color-difference signals are transferred to lower frequencies (approximately 1.1 MHz), which made it possible to minimize the influence of the inconsistency of the tape speed on the color quality.

Comparison of formats

A list of the main differences between the standards is summarized in the table. As you can see, there are significant differences in carrier frequencies and the total frequency band occupied in communication channels.

However, today readers are unlikely to have to suffer seriously because of problems, incompatibility of formats. Whichever way you output video from a computer, there will almost always be a choice of at least two formats PAL or NTSC.

Many people think that a regular Japanese monitor for a right-hand drive car is a toy useless for Russia. On many forums you can hear - "there is NTSC format, but in Russia Pal, and nothing can be done about it." This is not entirely true.

At the same time, functions that are available for left-hand drive cars, even in budget versions, have become familiar to us:

• to have normal "music" in the car,
• so that the child can be shown cartoons on the road,
• to read MP3 from a flash drive,
• to connect a rear view camera, and for a right-hand drive and overtaking camera

In general, everything should be "normal". Instead, the floor of the panel is occupied by an almost useless Japanese head, which can hardly catch the radio.

There are different ways to solve this problem.

I. Replacement of the standard head unit.

Pros: As a rule, these are modern 2Din devices, which have a large set of functions:

• playing music and video
• USB port and card reader
• connection of overtaking camera and rear view
• infrared remote control or joystick on the steering wheel
• Bluetooth to connect to phone
• and even GPS

• the price of such "combines" can be from 20 tons. and higher.
• the installation price can be up to half the cost of the radio
• the original appearance panels. Often, the plastic panel inserts may not fit the new radio tape recorder and there are gaps on the sides.

And sometimes replacement is simply impossible, because the OEM monitor can display information on the control of some car systems (climate control, on-board computer settings, clock, etc.)

II. Adaptation of the OEM monitor. Installation of a TV tuner-transcoder that converts any signals to NTSC.

• all functions of the standard device are saved
• it becomes possible to connect a regular DVD recorder or car cameras and display the image on the standard screen
• interior appearance is preserved
• shows Russian TV

• price for a transcoder from 11 tr.
• the price for installation in the brand center of the absolute can reach the cost of a transcoder
• with these investments, we get the function of Russian TV and ONLY the POSSIBILITY (!) to connect additional devices (car cameras and DVDs), which again will require additional costs.
• But in general, the solution is very good, if you do not take into account the price.

III. Use NTSC devices. And there are not so few of them!

1. For example, overtaking cameras KPC-S28 and KPC-DNR880 are available in NTSC version - they can be connected directly without any transcoders and adapters. And they will immediately give a good, clear, non-transcoded image to the OEM monitor of a right-hand drive car.
2. Also, most car radio can transmit signal in both formats and Pal and Ntsc. Simple statistics:
   • on the Yandex.market there are descriptions of 2438 car DVD players,
   • 1917 of them have a video output (i.e. can display an image on an external monitor),
   • of which 1649 can output image in nTSC format... Those. can be connected to a standard Japanese head unit without any expensive transcoders !!!

   Almost all of them have a USB input and can read any audio and video formats and display the image on the OEM monitor.

   And the price for them is very, very democratic - from 1,500 rubles.

   It is not necessary to install it in the central panel, but anywhere - in the glove compartment, under the seat, etc. However, then you will have to pick up a radio tape recorder with a control panel and buy USB extension cable for flash drives (100-200 rubles). And all this will work without expensive transcoders and absolutes.

   An example of such a connection can be found in the photo report:

   
   

   IN this example, you will see for very little money the standard system has been supplemented with new functions - watching DVD discs (all formats), MP3 music, reading data from a USB flash drive, and an overtaking camera is connected. At the same time, the appearance of the panel is completely preserved, all the standard functions of the standard device, the “native” rear-view camera works in the standard format.

   But when using a regular monitor, you need to take into account some of the nuances:

   • blocking video when moving. As a rule, for safety reasons, the ability to watch video while driving is blocked on Japanese cars. Locks can be different - for ignition, parking brake, etc. This problem has been solved long ago, and all cars have solutions on the appropriate forums - how to remove all locks. In a normal car repair shop, they can remove the video block for little money.
   • you may want to connect multiple video devices to one video input, such as overtaking camera, rear view camera and car dvd player. If you do not plan to use them at the same time, you can connect all devices to one video input using a simple double / tee for an RCA plug (100 rubles) or simply by connecting the appropriate wires. If one device is turned on, the corresponding picture will be shown on the monitor. If 2 or more devices are turned on, then the monitor simply does not recognize the video signal and will not show anything, or it will show ripples - nothing can burn out from such a connection. This option is quite justified if you use 2 cameras - overtaking and rear view. As a rule, there are no situations of simultaneous use of both cameras. But if you plan to connect a DVD, then it is better to do it through a relay, because turning off the radio tape recorder every time you need to turn on the camera is not very convenient. An example of such a connection through a relay is in the above photo report. Again, in a normal car service, 2-3 devices will be connected to one video input through a relay, and this should not be expensive (the cost of the relay itself is 30 rubles).

   The purpose of this article is to dispel prejudices about the uselessness of regular NTSC monitors.

   Perhaps for some, much of what has been said here will not be news, because similar topics, one way or another, pop up on various forums. We will try to surprise even experienced specialists with such "exotic options":

Displaying an image on a standard Japanese monitor from a cell phone. Few people know, but some phone models can display images in analog format. For example, Nokia 5800 XpressMusic, Nokia N97 mini, Samsung Galaxy S I9000 (Android), etc. can display images and music on any monitor using a standard 3.5 jack-3RCA video cable (150 rubles) and all have NTSC support. Everything iPhone models you can also connect to the video input of the head unit using special cable... Thus, if the phone has navigation programs - you can display the image on the OEM monitor, and voice prompts on the car speakers. But, unfortunately, phones with analog video output are no longer produced (except for the IPhone), most manufacturers have switched to HDMI video output. However, it may be one of the few adaptations (in quotes) of Japanese navigation.

Connecting a media player. Despite the fact that media players have appeared relatively recently, according to the Yandex.market data, there are already more than 600 models. To connect in a car, consider miniature models with the ability to install hard disk from the laptop. These models are convenient for their small size - a little more than a pack of cigarettes. The player can be placed anywhere in the cabin or on the torpedo; it takes up little space and will not spoil the look. Almost all models have a remote control, read USB sticks and SD cards, support both Pal / Ntsc formats. Most support both formats, but it's best to check. An important point (!). All these devices operate on 220 volts via an external power supply. But most of the "native" voltage is 5V. For example, the Qumo Home Base HB001, Supra MP-13, iconBIT HD277HDMI models - all can be powered by 5V, NTSC support, a slot for a hard drive, USB, SD, read all video and audio formats cost between 1500-2000 rubles. To get 5V from car 12V, you can use a regular cigarette lighter / USB charger. After all, the standard USB voltage is exactly 5V. For a player with a hard drive, you need to choose a 1.5-2A charger, without a hard drive, 1-1.5A is enough. If there is no usual USB charging with high current, you can use chargers from GPS navigators or smartphones. As a rule, they all have parameters 5V and 1.5-2A.
Thus, we can connect the player directly to the car network without using bulky adapters with direct current for 220V and vice versa. As a result, we will get a very inexpensive solution that will allow you to watch movies on a standard monitor and listen to music from a flash drive. Nothing will prevent us from connecting overtaking and rear-view cameras to this video input, as described above. The main thing is that the format of the cameras would be NTSC.

We would like to develop the use of NTSC devices, and we regularly hold a promotion - if you can make a good photo report on connecting an overtaking camera, media player, cell phone or other device to the car radio, take part in the action "1500 rubles for a photo report." Describe your idea to us, make a good photo report and we will pay you money or send you an overtaking camera for free.

Good luck to everyone on the road. Love your car and he will answer you in kind.

| PAL (abbreviated from Phase Alternating Line) - standard analog television... A color coding system used in television systems around the world. This system has a resolution of 625 lines at 25 frames (50 fields) per second.

PAL history

In the 1950s, when mass-producing color TVs in Western Europe, developers faced a problem found in the NTSC standard. The system showed a number of shortcomings, the main one of which was the image color shift under poor signal reception conditions. Subsequently, to overcome the shortcomings of NTSC, alternative PAL and SECAM standards were developed. The new standard was intended for color television in European countries, had a frequency of 50 fields per second (50 hertz), and did not have the disadvantages of NTSC.

The PAL standard was developed by Walter Bruch at Telefunken in Germany. The first broadcasts of the new standard were made in Great Britain in 1964, then in Germany in 1967.

Telefunken was later acquired by French electronics manufacturer Thomson. The company also acquired the founder of the European SECAM standard, Compagnie Générale de Télévision. Thomson (now Technicolor SA) holds an RCA license from Radio Corporation of America, the founder of the NTSC standard.

In television systems, the term PAL is often interpreted as 576i (625 lines / 50 Hz), NTSC as 480i (525 lines / 60 Hz). The symbols on DVD discs of PAL or NTSC standard indicate the method of color reproduction, although the composite color itself is not recorded on them.

Color coding

As with NTSC, the pAL system uses amplitude modulation with a chroma balance subcarrier added to the luminance of the composite video signal. The subcarrier frequency for PAL signal is 4.43361875 MHz, compared to 3.579545 MHz for NTSC. On the other hand, SECAM uses frequency modulation with two alternate color lines, whose subcarriers are 4.25000 and 4.40625 MHz.

The very name of the standard " Phase Alternating Line"indicates that the phase part of the color information in the video signal is restored from each line, which automatically corrects errors in signal transmission, canceling them, due to the vertical resolution. The lines where the color is restored are often called PAL or phase interleaving of lines, while as other lines are called NTSC lines.The first PAL TVs were very irritating to the human eye due to the so-called picture comb effect, also known as Hanover bars, which occurs when phase errors occur. Thus, most receivers began to use delay lines in color. storing information about the received color in each line of the kinescope.The disadvantage of the PAL system is the vertical color resolution, which is poorer than in NTSC, but since the human eye has the same color resolution, then this effect is not visible.

The typical subcarrier frequency is 4.43361875 MHz and consists of 283.75 color clocks per line plus an offset of -25 Hz to avoid interference. Since the horizontal frequency is 15625 Hz (625 lines x 50 Hz / 2), the carrier color is calculated as: 4.43361875 MHz \u003d 283.75 * 15625 Hz + 25 Hz.

The initial color subcarrier is required for the decoder to correct color differences. Since the color subcarrier is not transmitted along with the video information, it must be generated in the receiver. In order for the phase of the generated signal to correspond to the transmitted information, 10 cycles of “color flashes” of the subcarrier are added to the video signal.

Advantages of PAL over NTSC

For NTSC receivers, color adjustment can be performed manually. If the color is incorrectly adjusted, the color display may be erroneous. The PAL standard automatically changes color. PAL chroma phase errors have been eliminated with a 1H delay line, resulting in a degradation in color saturation that is not as noticeable to the human eye as in NTSC.

However, even in PAL systems, color interleaving (Hanover Bars) - can lead to graininess due to phase errors if first generation decoders are used. Often, these extreme phase shifts do not occur. Usually, this effect is observed when obstacles occur during the passage of the signal, and is observed in heavily built-up areas. The effect is more noticeable at ultra high frequencies (UHF) than at VHF.

In the early 1970s, some Japanese manufacturers developed new decoding techniques to avoid paying royalties to Telefunken. The Telefunken license provided for any decoding method that would reduce the phase distortion of the phase subcarrier. One development was to use a 1H delay line to decode only odd or even lines. For example, chroma on odd lines was turned on directly at the decoder, keeping the delay lines. Then, on even lines, the stored odd lines were decoded again. This method effectively converts PAL system to NTSC. Such systems also have their disadvantages associated with NTSC and require the addition of manual control over color tints.

PAL and NTSC standards have several different color spaces, but color differences are ignored thanks to the decoder.

PAL advantages over SECAM

The first attempts at alignment with color TVs were made in the SECAM standard, which also had the problem of NTSC shades. Achieved by applying different methods color transmission, namely alternative transmission of U and V vectors and modulation frequencies.

SECAM is more reliable for long distance signal transmission than NTSC or PAL. However, due to its nature, the color signal is retained only in a distorted form due to the decrease in amplitude, even in the black and white part of the image (color overlap occurs). Also PAL and SECAM receivers need delay lines.

PAL signal characteristics

The PAL-B / G signal has the following characteristics.

PAL system types

* PAL I system has never been used on UK VHF frequencies

VHF - Very High Frequency (VHF)

UHF - Ultra High Frequency (UHF)

PAL-B / G / D / K / I

Most countries using PAL standards broadcast at 625 lines at 25 frames per second. The systems differ only in the carrier frequency of the audio signal and in the channel bandwidth. PAL B / G standards are used in most countries in Western Europe, Australia and New Zealand, United Kingdom, Ireland, Hong Kong, South Africa and Macau. PAL D / K standards in most CEE countries, PAL D standard in China. Analog CCTV cameras use the PAL D standard.

PAL B and PAL G systems are very similar. System B uses 7 MHz and wide channels on VHF, while System G uses 8 MHz and UHF. Systems D and K are also similar: System D is used only at VHF, while System K is used only at UHF.

PAL-M (Brazil)

In Brazil, the PAL system uses 525 lines and 29.97 fps of the M system, while using the NTSC color subcarrier. The exact frequency of the PAL-M color subcarrier is 3.575611 MHz.

The PAL color system can also be NTSC, 525-line (480i) images are often called PAL-60 (sometimes PAL-60/525, Quasi-PAL or Pseudo PAL). PAL is a broadcast standard, not to be confused with PAL-60.

PAL-N (Argentina, Paraguay, Uruguay)

This version of the system is used in Argentina, Paraguay and Uruguay. It employs 625 lines / 50 fields per second, the signal is from PAL-B / G, D / K, H, I. And the 6 MHz channel with a color subcarrier frequency of 3.582 MHz is very similar to NTSC.

VHS tapes recorded with PAL-N or PAL-B / G, D / K, H, I do not differ due to the down-conversion of the subcarriers on the tape. VHS recorded from TV in Europe will be played back in PAL-N color. In addition, any tape recorded in Argentina or Uruguay with PAL-N television broadcasts can be played back in European countries that use PAL (Australia, New Zealand, etc.)

Typically, people in Uruguay, Argentina and Paraguay own TVs that also display the NTSC-M standard, in addition to PAL-N. Live TV broadcast is also used in NTSC-M for North, Central and South America. Most DVD players sold in Argentina, Uruguay and Paraguay only play PAL discs (color subcarrier frequency 4.433618 MHz).

Some DVD players using a signal transcoder can encode NTSC-M, with some loss in picture quality by converting the system from 625/50 PAL DVD to NTSC-M format (525/60 output).

Advanced features of the PAL specification such as teletext are implemented in PAL-N. PAL-N supports 608 closed caption change, which is designed to facilitate NTSC compatibility.

PAL-L

The PAL L (Phase L sound system) standard uses the same video system with PAL-B / G / H quality (625 lines, 50 Hz, 15.625 kHz), but with a bandwidth of 6 MHz instead of 5.5 MHz. This requires an audio subcarrier of 6.5 MHz. The channel spacing used for PAL-L is 8 MHz.

PAL standards compatibility

The PAL color system is usually used in conjunction with video formats that have 625 lines per frame (576 visible lines, the rest are used for service information, data synchronization and subtitles) and a refresh rate of 50 interlaced fields per second (i.e. 25 full frames per second). such as B, G, H, I, and N.
PAL guarantees video compatibility. However, some of the standards (B / G / H, I and D / K) use different audio frequencies (5.5 MHz, 6.0MHz 6.5MHz respectively). This can result in video without audio if the signal is transmitted over cable TV... In some Eastern European countries that previously used SECAM D and K systems, they switched to PAL, thus paying more attention to the video signal. As a result, it became necessary to use various sound carriers.

Today TV broadcasts offer the latest in playback formats, but you can still hear standards like PAL or NTSC on a regular basis. What is better and what is the difference between them? To understand this, you need to get an understanding of each of these standards.

What is NTSC?

So, many American video media are in NTSC format. What it is? Today it is the color coding system used by DVD players. Until recently, it was used by broadcast television in North America, Japan, and most of South America.

As color TVs began to replace black and white TVs, developers began to use several different color coding methods for broadcast. However, these methods contradicted each other and the old black and white televisions, which could not interpret the color signals they transmitted. In 1953, the National Systems Committee adopted the NTSC standard, which was developed and implemented as a single standard. From that point on, it could be used all over the country, as it became compatible with a large number of different TVs. NTSC can still be found nowadays. What does it mean? Even though modern TVs no longer use this format, they can still accept and distinguish it.

What is PAL format?

Before deciding which is better - PAL or NTSC, you need to figure out how they differ from each other.

The PAL format is a color coding system used by DVD players and broadcast televisions in Europe, most of Asia and Oceania, Africa, and parts of South America.

Phase Alternating Line or PAL formatting, along with the SECAM standard (previously used in Russia and the CIS, the image in this method is broadcast as sequential color with memory), was developed in the late 1950s to get around certain disadvantages of the NTSC system.

Since NTSC encodes color, this means the signal can lose clarity in poor conditions, so early systems built with this format were vulnerable in bad weather, in large buildings, and some other factors. To solve this problem, the PAL video format was created. It works as follows - during translation, it changes every second line in the signal, effectively eliminating errors.

Unlike NTSC, PAL is still often used for broadcasting in the regions in which it was adopted.

PAL vs NTSC: Which is Better to Use?

Many video editing programs, such as VideoStudio, allow you to choose which format to save your work in when burning to DVD.

Which format you should use depends mainly on your location. If you are creating videos that will be displayed around the world, NTSC of your choice is safer and more comfortable. Most DVD players and other PAL devices can play NTSC video, while NTSC players generally do not support PAL.

Why are these formats still in use?

The main answer is that today they are not what they were originally created. Obviously, the technical problems that these coding systems were created to solve in the 1950s do not apply to the modern world. However, DVDs are still marked with NTSC or PAL support (see above for what to buy and why), and the timings, resolutions and refresh rates set on these systems are still used in modern TVs and monitors.

The main reason for this is the regionalization of content. The use of various video formats acts as a layer of physical protection to strengthen national copyright laws and prevent the distribution of films and television programs in different countries without permission. In fact, this is the use of formats as a legal method of copyright protection. This phenomenon is so common that the distribution areas for video games and other interactive electronic media often referred to as NTSC and PAL regions, although such software works great on any type of display.

PAL, NTSC: what is the difference from a technical point of view?

Televisions show their images line by line and create the illusion of movement by displaying them slightly altered, many times per second. The broadcast signal for black and white television simply indicated the level of brightness at each point along the line, so each frame was just a signal with luminance information for each line.

Originally, TVs displayed 30 frames per second (FPS). However, when color was added to widescreen broadcasting, black and white TVs could not distinguish color information from luminance information, so they tried to display the color signal as part of the picture. As a result, it became meaningless, and there was a need to introduce a new TV standard.

To display color without this problem, the broadcast needed to add a second chroma signal between the fluctuations in the luminance signal, which would be ignored by black and white TVs, and color devices would search for it and display it using an adapter called a Colorplexer.

Since this additional signal was added between each frame refresh, it increased the amount of time to change them, and the actual FPS on the display was reduced. Therefore, NTSC TV plays back 29.97 frames per second instead of 30.

In turn, the PAL signal uses 625 lines, of which 576 (known as the 576i signal) are displayed as visible lines on the TV, while the NTSC formatted signal uses 525 lines, of which 480 appear to be visible (480i). In PAL video, every second line has a phase change in the color signal, which causes them to equalize the frequency between the lines.

What does it mean?

In terms of effect, this means that signal damage appears as a saturation error (color level) rather than a hue (color cast) as it would in NTSC video. This resulted in a more highly accurate picture of the original image. However, the PAL signal loses some vertical color resolution, making the colors at the junction of the lines a little washed out, although this effect is not visible to the naked human eye. On modern DVDs, the signal is no longer encoded on the basis of line joining, so there are no frequency and phase differences between the two formats.

The only real difference is the resolution and frame rate at which the video is played.

Conversion from NTSC to PAL and vice versa

If PAL video is converted to NTSC tape, add 5 extra frames per second. Otherwise, the image may appear choppy. For an NTSC movie converted to PAL, the opposite applies. Five frames per second must be removed, or the action on the screen may appear unnaturally slow.

PAL and NTSC on HDTVs

There is a wide analog system for television, therefore, despite the fact that digital signals and high definition (HD) become the universal standard, variations remain. The primary visual difference between NTSC and PAL systems for HDTV is the refresh rate. NTSC refreshes the screen 30 times per second, while PAL systems refreshes the screen per second. For some types of content, especially images with high resolution (such as generated by 3D animation), HDTVs using the PAL system may show a slight tendency to flicker. However, the picture quality is NTSC and most people won't notice any problems.

It is not encoded on a carrier wave basis, so there are no frequency and phase differences between the two formats. The only real difference is the resolution and the frame rate (25 or 30) at which the video is played.

2 years ago