What is the difference between PAL and NTSC?

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What is the difference between PAL and NTSC?

1. NTSC system NTSC system is also called grace system. It belongs to the simultaneous system. It was first developed by the United States in December 1953 and was named after the National Television System Committee (National Television System Committee). The chrominance signal modulation feature of this system is the balanced quadrature amplitude modulation system, which includes balanced modulation and quadrature modulation. Although it solves the problem of compatibility between color TV and black-and-white TV broadcasting, the phase is easily distorted and the color is not correct. The disadvantage of being too stable. The power supply frequency of NTSC TV is 60 Hz, the field frequency is 60 fields per second, the frame frequency is 30 frames per second, the scanning line is 525 lines, and the image signal bandwidth is 6.2 MHz. The United States, Japan and other countries that adopt the NTSC system.


2. PAL system PAL system is also called account system. It is to overcome the NTSC system's sensitivity to phase distortion. In 1962, the former Federal Germany developed an improved scheme based on the comprehensive NTSC system's technical achievements. PAL is the abbreviation of Phase Alteration Line in English, which means phase alternation line by line, which is also a simultaneous system. It uses line-by-line phase inversion for one of the two color-difference signals transmitted at the same time, and the other color-difference signal performs quadrature modulation. In this way, if phase distortion occurs during signal transmission, the phases of the adjacent two rows of signals will be opposite to each other, thereby effectively overcoming the color change caused by the phase distortion. Therefore, the PAL system is not sensitive to phase distortion, the image color error is small, and it is compatible with black and white TV. However, the encoder and decoder of the PAL system are more complicated than the NTSC system, and the signal processing is more troublesome. The cost of the receiver Also high. Since countries all over the world have to consider compatibility with black-and-white TV when setting up color TV broadcasts, many countries adopt the PAL system, such as my country, Germany, Singapore, and Australia. However, we still need to pay attention to a problem. Since the black and white TV standards adopted by various countries are not the same, even if the PAL system is also mentioned, there will still be differences in some technical characteristics. The power supply frequency of PAL TV is 50 Hz, the field frequency is 50 fields per second, the frame frequency is 25 frames per second, the scanning line is 625 lines, and the image signal bandwidth is 4.2, 5.5, 5.6 MHz, etc. respectively. /////////////////////////////////////////////NTSC/PAL the difference



To put it simply, NTSC and PAL are the two major television broadcasting systems in the world, but they differ depending on the frequency at which the system projects color images. NTSC is the abbreviation of National Television System Committee. Its standards are mainly used in Japan, the United States, Canada, Mexico, etc., while PAL is the abbreviation of Phase Alternating Line, which is mainly used in China, Hong Kong, the Middle East and Europe. These two systems are not compatible with each other. If you play NTSC video on a PAL TV, the screen will become black and white, and the same is true for NTSC. 2. NTSC and PAL are just two different video formats in the final analysis. The main difference is that NTSC is 60 fields per second and PAL is 50 fields per second. Since the current TV adopts interlaced mode, NTSC can get 30 video formats per second. Complete video frames, while PAL can get 25 complete video frames per second. What is the difference between this subtle difference of one frame per second in the performance of DVD? As we all know, the speed of movie film is 24 frames per second, and the DVD of PAL system will play one more frame per second than film, that is to say. For the same movie, PAL’s projection speed will be 1/24 higher than that of film; then NTSC can get 30 video frames per second. Will it be faster than PAL? In fact, it’s not. NTSC adopts 3-2PULLDOWN technology to convert the movie. At 30 frames per second. For movies of the same length, the conversion of the screening time between NTSC and PAL is: NTSC time X 24/25 = PAL time. DVD produces 480 scan lines for NTSC standard moving images, and PAL standard is 576 lines. The NTSC standard has a total of 525 scan lines, but only about 480 to 483 lines are visible. (The other lines are black and contain sync pulses and other information. For example, CC subtitles are encoded in line 21.) There are 625 scan lines in the PAL system, but only lines 576 to 580 are visible. Since all video formats (VHS, LD, broadcast, etc.) have the same number of scan lines, it is actually the horizontal resolution line that affects the picture quality.


Common TV signal formats are PAL and NTSC, in addition to SECAM and so on. NTSC stands for Quadrature Balanced Amplitude Modulation System. PAL is a progressive reverse image quadrature balanced amplitude modulation system. PAL TV standard PAL TV standard, 25 frames per second, TV scanning line is 625 lines, odd field first, even field behind, standard digital PAL TV standard resolution is 720*576, 24-bit color depth, picture The aspect ratio is 4:3, and the PAL TV standard is used in China, Europe and other countries and regions. NTSC TV standard NTSC TV standard, 29.97 frames per second (simplified to 30 frames), TV scanning line is 525 lines, even field first, odd field behind, standard digital NTSC TV standard resolution is 720*486, 24 bits The color depth of, the aspect ratio of the picture is 4:3. The NTSC TV standard is used in the United States, Japan and other countries and regions. The ntsc system has 29.97 frames per second. The pal system has 25 frames per second. Both ntsc and pal systems are interlaced. Therefore all contain fields. ntsc is an even field. pal is an odd field. It can be simply understood that the first frame of ntsc is displayed as 2, 4, 6, 8... lines. The first frame of pal is displayed as 1, 3, 5, 7, 9... lines. There are 525 horizontal lines in each frame of the NTSC TV full-screen image. The lines are arranged from left to right and top to bottom. Every other line is jumping. So each complete frame needs to scan the screen twice: the first scan is an odd line, and the other scan is an even line. Each half-frame screen scan takes about 1/60 second; the full frame scan takes 1/30 second. This interlacing system is also called interlacing (also meaning interlacing). The adapter can convert the NTSC signal into a digital signal that the computer can recognize. On the contrary, there is a kind of equipment that can convert computer video to NTSC signal, and can use the TV receiver as a computer monitor. However, since the resolution of a general-purpose TV receiver is lower than that of an ordinary monitor, no matter how large the TV screen is, it cannot adapt to all computer programs. PAL is the abbreviation of Phase Alteration Line in English, which means phase alternation line by line, which is also a simultaneous system. It uses line-by-line phase inversion for one of the two color-difference signals transmitted at the same time, and the other color-difference signal performs quadrature modulation. In this way, if phase distortion occurs during signal transmission, the phases of the adjacent two rows of signals will be opposite to each other, thereby effectively overcoming the color change caused by the phase distortion. Definitions and differences between PAL and NTSC systems Most AV players know that NTSC (National Television System Committee) represents a television system standard widely used in the world. In fact, NTSC is created by EIA (Electronic Industries Association of America) Initiated and founded. NTSC has also established a monochrome (black and white) television standard, which was passed and approved by the FCC (Federal Communications Commission) in 1941. In fact, around 1949, color television broadcasting was still in the experimental stage. At that time, two strong competitors, RCA and CBS, were bidding for the U.S. color television standards. Finally, NTSC adopted the RCA standard and modified it, and the FCC also The NTSC standard is recognized, making NTSC a color TV standard common to the United States, Canada, Japan, my country, and many countries in the Western Hemisphere. Why did CBS fail? One of the main key points is that the CBS color TV system is not compatible with the original monochrome TV system. Today's NTSC TV system related products: video recorders, video disc players, camcorders... all It can be fully compatible with black and white monochrome TVs. These were all laid down in the same year. RCA adopted quite amazing technology to achieve the purpose of transmitting color images within the limited bandwidth of the original black and white monochrome TVs. Even today It seems that the invention of the NTSC color TV system is still quite incredible. The later TV stereo and MTS bilingual functions actually laid the technical foundation as early as 1949. Common TV signal formats are PAL and NTSC, in addition to SECAM and so on. NTSC stands for Quadrature Balanced Amplitude Modulation System. PAL is a progressive reverse image quadrature balanced amplitude modulation system. PAL TV standard PAL TV standard, 25 frames per second, TV scanning line is 625 lines, odd field first, even field behind, standard digital PAL TV standard resolution is 720*576, 24-bit color depth, picture The aspect ratio is 4:3, and the PAL TV standard is used in China, Europe and other countries and regions. NTSC TV standard NTSC TV standard, 29.97 frames per second (simplified to 30 frames), TV scanning line is 525 lines, even field first, odd field behind, standard digital NTSC TV standard resolution is 720*486, 24 bits The color depth of, the aspect ratio of the picture is 4:3. The NTSC TV standard is used in the United States, Japan and other countries and regions. The difference between PAL and NTSC systems lies in the color coding and decoding methods and field scanning frequencies of the programs. China (excluding Hong Kong), India, Pakistan and other countries adopt the PAL system, while the United States, Japan, South Korea, and my country's Taiwan region adopt the NTSC system. The difference between PAL and NTSC film is 24 film frames per second. The video image PAL system is 50 fields per second, and the NTSC system is 60 fields per second. Since the current televisions are all interlaced fields, it can be roughly considered that the PAL system has 25 complete video frames per second and the NSTC system has 30 complete video frames. The difference between film and PAL is only 1 frame per second, so in the past, generally speaking, one frame was produced directly, so that PAL would play one more frame per second than film, that is, the speed increased by 1/24, and the pitch of the sound Will rise. This is one of the reasons why some DVD lovers do not like PAL DVDs. But it is said that some PAL DVDs now adopt a 24+1 production method, which is to repeat one of the 24 frames to obtain the same playback speed as the movie. However, NTSC has 30 frames per second and cannot directly produce one frame to one frame. Therefore, it is necessary to convert 24 movie frames into 30 video frames through 3-2 PULLDOWN and other methods. The content contained in these 30 video frames and 24 movie frames are equal, so the playback speed of NTSC is the same as that of movies. Therefore, for the same movie, a PAL DVD will be 1/24 faster than the same NTSC movie. When converting time, NTSC time X 24/25 = PAL time.