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NTSC-J or "System J" is the informal designation for the analogue television standard used in Japan. The system is based on the US NTSC (NTSC-M) standard with minor differences. [1] While NTSC-M is an official CCIR [2] [3] [4] and FCC [5] [6] [7] standard, NTSC-J or "System J" are a colloquial indicators.
The system was introduced by NHK and NTV, with regular color broadcasts starting on September 10, 1960. [8] [9]
NTSC-J was replaced by digital broadcasts in 44 of the country's 47 prefectures on 24 July 2011. Analogue broadcasting ended on 31 March 2012 in the three prefectures devastated by the 2011 Tōhoku earthquake and tsunami (Iwate, Miyagi, Fukushima) and the subsequent Fukushima Daiichi nuclear disaster.
The term NTSC-J is also incorrectly and informally used to distinguish regions in console video games, which use televisions (see Marketing definition below).
Japan implemented the NTSC standard with slight differences. The black and blanking levels of the NTSC-J signal are identical to each other [10] (both at 0 IRE, similar to the PAL video standard), while in American NTSC the black level is slightly higher (7.5 IRE) than blanking level - because of the way this appears in the waveform, the higher black level is also called pedestal. This small difference doesn't cause any incompatibility problems, but needs to be compensated by a slight change of the TV brightness setting in order to achieve proper images.
YIQ color encoding in NTSC-J uses slightly different equations and ranges from regular NTSC. has a range of 0 to +-334 (+-309 on NTSC-M), and has a range of 0 to +-293 (+-271 on NTSC-M). [11]
YCbCr equations for NTSC-J are , while on NTSC-M we have . [11]
NTSC-J also uses a white reference (color temperature) of 9300K instead of the usual NTSC standard of 6500K. [12] [13] [14]
The over-the-air RF frequencies used in Japan do not match those of the US NTSC standard. On VHF the frequency spacing for each channel is 6 MHz as in North America, South America, Caribbean, South Korea, Taiwan, Burma (Myanmar) the Philippines, except between channels 7 and 8 (which overlap). Channels 1 through 3 are reallocated for the expansion of the Japanese FM band. On UHF frequency spacing for each channel in Japan is the same, but the channel numbers are 1 lower than on the other areas mentioned - for example, channel 13 in Japan is on the same frequency as channel 14. For more information see Television channel frequencies. Channels 13-62 are used for analog and digital TV broadcasting.
The encoding of the stereo subcarrier also differs between NTSC-M/MTS and Japanese EIAJ MTS broadcasts. [15]
The term NTSC-J was informally used to distinguish regions in console video games, which use televisions. NTSC-J is used as the name of the video gaming region of Japan (hence the "J"), South East Asia (some countries only), Taiwan, Hong Kong, Macau, Philippines and South Korea (now NTSC-K) (formerly part of SE Asia with Hong Kong, Taiwan, Japan, etc.). [16] [17]
Most games designated as part of this region will not run on hardware designated as part of the NTSC-U, PAL (or PAL-E, "E" stands for Europe) or NTSC-C (for China) mostly due to the regional differences of the PAL (SECAM was also used in the early 1990s) and NTSC standards. [18] [19] [20] [17] Many older video game systems do not allow games from different regions to be played (accomplished by various forms of regional lockout); however more modern consoles either leave protection to the discretion of publishers, such as Microsoft's Xbox 360, or discontinue its use entirely, like Sony's PlayStation 3 (with a few exceptions).
China received its own designation due to fears of an influx of illegal copies flooding out of China, which is notorious for its rampant copyright infringements. There is also concern of copyright protection through regional lockout built into the video game systems and games themselves, as the same product can be edited by different publishers from one continent to another.
Frequency modulation synthesis is a form of sound synthesis whereby the frequency of a waveform is changed by modulating its frequency with a modulator. The (instantaneous) frequency of an oscillator is altered in accordance with the amplitude of a modulating signal.
In classical mechanics, a harmonic oscillator is a system that, when displaced from its equilibrium position, experiences a restoring force F proportional to the displacement x: where k is a positive constant.
NTSC is the first American standard for analog television, published in 1941. In 1961, it was assigned the designation System M. It is also known as EIA standard 170.
Phase Alternating Line (PAL) is a colour encoding system for analog television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields per second, and associated with CCIR analogue broadcast television systems B, D, G, H, I or K. The articles on analog broadcast television systems further describe frame rates, image resolution, and audio modulation.
SECAM, also written SÉCAM, is an analog color television system that was used in France, Russia and some other countries or territories of Europe and Africa. It was one of three major analog color television standards, the others being PAL and NTSC. Like PAL, a SECAM picture is also made up of 625 interlaced lines and is displayed at a rate of 25 frames per second. However, due to the way SECAM processes color information, it is not compatible with the PAL video format standard. SECAM video is composite video because the luminance and chrominance are transmitted together as one signal.
In telecommunications and signal processing, baseband is the range of frequencies occupied by a signal that has not been modulated to higher frequencies. Baseband signals typically originate from transducers, converting some other variable into an electrical signal. For example, the electronic output of a microphone is a baseband signal that is analogous to the applied voice audio. In conventional analog radio broadcasting, the baseband audio signal is used to modulate an RF carrier signal of a much higher frequency.
A heterodyne is a signal frequency that is created by combining or mixing two other frequencies using a signal processing technique called heterodyning, which was invented by Canadian inventor-engineer Reginald Fessenden. Heterodyning is used to shift signals from one frequency range into another, and is also involved in the processes of modulation and demodulation. The two input frequencies are combined in a nonlinear signal-processing device such as a vacuum tube, transistor, or diode, usually called a mixer.
Multichannel Television Sound (MTS) is the method of encoding three additional audio channels into analog 4.5 MHz audio carriers on System M and System N. It was developed by the Broadcast Television Systems Committee, an industry group, and sometimes known as BTSC as a result.
YIQ is the color space used by the analog NTSC color TV system. I stands for in-phase, while Q stands for quadrature, referring to the components used in quadrature amplitude modulation. Other TV systems used different color spaces, such as YUV for PAL or YDbDr for SECAM. Later digital standards use the YCbCr color space. These color spaces are all broadly related, and work based on the principle of adding a color component named chrominance, to a black and white image named luma.
The Butterworth filter is a type of signal processing filter designed to have a frequency response that is as flat as possible in the passband. It is also referred to as a maximally flat magnitude filter. It was first described in 1930 by the British engineer and physicist Stephen Butterworth in his paper entitled "On the Theory of Filter Amplifiers".
An LC circuit, also called a resonant circuit, tank circuit, or tuned circuit, is an electric circuit consisting of an inductor, represented by the letter L, and a capacitor, represented by the letter C, connected together. The circuit can act as an electrical resonator, an electrical analogue of a tuning fork, storing energy oscillating at the circuit's resonant frequency.
An ion trap is a combination of electric and/or magnetic fields used to capture charged particles — known as ions — often in a system isolated from an external environment. Atomic and molecular ion traps have a number of applications in physics and chemistry such as precision mass spectrometry, improved atomic frequency standards, and quantum computing. In comparison to neutral atom traps, ion traps have deeper trapping potentials that do not depend on the internal electronic structure of a trapped ion. This makes ion traps more suitable for the study of light interactions with single atomic systems. The two most popular types of ion traps are the Penning trap, which forms a potential via a combination of static electric and magnetic fields, and the Paul trap which forms a potential via a combination of static and oscillating electric fields.
The Rabi frequency is the frequency at which the probability amplitudes of two atomic energy levels fluctuate in an oscillating electromagnetic field. It is proportional to the transition dipole moment of the two levels and to the amplitude of the electromagnetic field. Population transfer between the levels of such a 2-level system illuminated with light exactly resonant with the difference in energy between the two levels will occur at the Rabi frequency; when the incident light is detuned from this energy difference then the population transfer occurs at the generalized Rabi frequency. The Rabi frequency is a semiclassical concept since it treats the atom as an object with quantized energy levels and the electromagnetic field as a continuous wave.
MUSE, commercially known as Hi-Vision was a Japanese analog high-definition television system, with design efforts going back to 1979.
Founded in 1948, the Electronic Industries Association of Japan (EIAJ) was one of two Japanese electronics trade organizations that were merged into the Japan Electronics and Information Technology Industries Association (JEITA).
Rec. 709, also known as Rec.709, BT.709, and ITU 709, is a standard developed by ITU-R for image encoding and signal characteristics of high-definition television.
CCIR System M, sometimes called 525–line, monochrome NTSC, NTSC-M, or CCIR-M, is the analog broadcast television system approved by the FCC for use in the United States since July 1, 1941, replacing the 441-line TV system introduced in 1938. System M comprises a total of 525 interlaced lines of video, of which 486 contain the image information, at 30 frames per second. Video is amplitude modulated and audio is frequency modulated, with a total bandwidth of 6 MHz for each channel, including a guard band.
Differential gain is a kind of linearity distortion that affects the amplification and transmission of analog signals. It can visibly affect color saturation in analog TV broadcasting.
Differential phase is a kind of linearity distortion which affects the color hue in TV broadcasting.
The color killer is an electronic stage in color TV receiver sets which acts as a cutting circuit to cut off color processing when the TV set receives a monochrome signal.
...it is standard for reference white to correspond to light having the spectral and/or colorimetric properties of CIE Illuminant D65 (except in Japan, where the standard white reference is 9300 K).
In Japan, the chromaticity of studio monitors is adjusted to a D-white at 9 300 K.
"D93: D93は9,305 K色温度であり、日本におけるモニタの基準白色として使用されている。" [D93 represents a color temperature of 9,305 K, and it is the white reference used for monitors in Japan.]