All countries have not adopted the same way of transmitting color signals. In France SECAM (Sequential Couleur A Memory), memorizes every other line to calculate the green. In the United States and other countries NTSC (phase change only one color differences): This is the first online videos and games system that was put in place, but it generates crosstalk which can be corrected by SECAM.
The challenge was to create a single signal encompassing three different information, and should not be mixed prior to treatment by the receiving station. The challenge was also to maintain full compatibility with the black and white positions still present in homes. Researchers are worked in order to create a video signal including red, green, blue, and black and white in the same "pipe" without them mingle.
The cameras, which function as an inverted TV also adopted this interlacing scan. As regards, the first half of an image, a 1st shot defines all the odd lines, and one half frame, a second shooting defines the even lines. The important thing to understand here is that two shots are distant in time (half image).
And even if these two shots are complementary to a spatial point of view (the two scans complement inside the frame), these two shots do not display the same content! If a subject moves in a field, it will have a different position on each of two fields: one then has a zigzag effect on each frame.
Free lines are partially taken advantage of: they place the signals teletext, subtitling and also the time-code of professional video equipment. There are two scanning frequencies of the image: The vertical scanning, which takes place from top to bottom is used to compose the image. It is done 50 or 60 times per second.
These solutions were found and implemented. Thus were developed in the United States (NTSC0, SECAM in France and PAL in Germany. Coding transforms RGB black/white color-compatible signal. NTSC, PAL and SECAM are three types of mutually incompatible encodings. Transformation from one type of encoding to another is called transcoding. None of the three solutions is nevertheless transparent, far from it. A transcoded signal suffers from more or less visible defects depending on the coding artifacts.
Analog video standard across the world include NTSC, PAL and SECAM. PAL or SECAM standards have no relationship with the scan of an image, these standards only allow you to add color to black and white images. In the early days of television, only the luminance defines the image by a number of horizontal dots and also by three factors shade of gray.
To remain compatible with black and white, the company carefully avoided RGB, and naturally selects a format containing the Y, plus information conveyed by two chrominance signals U and V (also known as Cr and Cb). These components are connected by formulas U = R - Y and V = B - Y, where Y = + 0,30R 0,59V 0,11B + (the coefficients being different according to the coding used). This transformation from RGB to YUV is called mastering. Metal stamping is a simpler coding operation that generates no degradation, while offering the advantage of compatibility Y.
The challenge was to create a single signal encompassing three different information, and should not be mixed prior to treatment by the receiving station. The challenge was also to maintain full compatibility with the black and white positions still present in homes. Researchers are worked in order to create a video signal including red, green, blue, and black and white in the same "pipe" without them mingle.
The cameras, which function as an inverted TV also adopted this interlacing scan. As regards, the first half of an image, a 1st shot defines all the odd lines, and one half frame, a second shooting defines the even lines. The important thing to understand here is that two shots are distant in time (half image).
And even if these two shots are complementary to a spatial point of view (the two scans complement inside the frame), these two shots do not display the same content! If a subject moves in a field, it will have a different position on each of two fields: one then has a zigzag effect on each frame.
Free lines are partially taken advantage of: they place the signals teletext, subtitling and also the time-code of professional video equipment. There are two scanning frequencies of the image: The vertical scanning, which takes place from top to bottom is used to compose the image. It is done 50 or 60 times per second.
These solutions were found and implemented. Thus were developed in the United States (NTSC0, SECAM in France and PAL in Germany. Coding transforms RGB black/white color-compatible signal. NTSC, PAL and SECAM are three types of mutually incompatible encodings. Transformation from one type of encoding to another is called transcoding. None of the three solutions is nevertheless transparent, far from it. A transcoded signal suffers from more or less visible defects depending on the coding artifacts.
Analog video standard across the world include NTSC, PAL and SECAM. PAL or SECAM standards have no relationship with the scan of an image, these standards only allow you to add color to black and white images. In the early days of television, only the luminance defines the image by a number of horizontal dots and also by three factors shade of gray.
To remain compatible with black and white, the company carefully avoided RGB, and naturally selects a format containing the Y, plus information conveyed by two chrominance signals U and V (also known as Cr and Cb). These components are connected by formulas U = R - Y and V = B - Y, where Y = + 0,30R 0,59V 0,11B + (the coefficients being different according to the coding used). This transformation from RGB to YUV is called mastering. Metal stamping is a simpler coding operation that generates no degradation, while offering the advantage of compatibility Y.
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