The luminance (luma) signal carries information about the brightness or brightness of the video scene and the chrominance signal carries color or chrominance information. Since the human eye's ability to perceive detail is most acute when viewing white light, light transmission carries the impression of fine detail. Luminance as different shades of light in grays while chroma are different hues of color. Colors have intensity while light has brightness. We see color in images because of light. In the absence of light, in total darkness, we do not see any colors.
The luminance signal is composed of a ratio of 30% red, 59% green and 11% blue from the color signal. This combined output becomes the luminance (brightness/monochromatic) signal. It is written as Y. RGB signal derived from camera or telesign by matrix or summation
A monochrome signal (Y signal) is commonly known as a black and white or grayscale signal. Black-and-white displays often use colored backlights such as green, blue, or orange.
A chrominance signal (chroma or C signal) is a signal used in video systems to convey image color information separately from the accompanying luma signal (Y signal)
The chrominance (chrome) signal in NTSC systems is an alternating current of precisely defined frequency (3.579545 ± 0.000010 MHz), which allows accurate recovery at the receiver even in the presence of strong noise or interference. The PAL (Phase Alternation Line) system is similar to the NTSC system in that the chrominance signal is simultaneously amplitude modulated to carry the color saturation (pastel-versus-vibrant) direction and phase modulated to carry the hue direction.
No comments:
Post a Comment