The difference between YUV and RGB in Image color space

http://blog.csdn.net/scg881008/article/details/7168637

If it is 2 million pixels of sensor, is not RGB a pixel is 2m,yuv is 1M? First of all, 2 million pixels of sensor, is a 2M pixel;
YUV is TV TransmissionA luminance signal (Y), two chromatic aberration signals (U component, v component)
YUV (also known as YCRCB) is a color coding method adopted by the European Television System ( belongs to PAL）。YUV is primarily used to optimize the transmission of color video signals, making them backwards compatible with older black and white。 Compared with the RGB video signal transmission, its greatest advantage is that onlyconsumes very little bandwidth(RGB requires three separate video signals to be transmitted simultaneously). Where "Y" represents luminance (luminance or luma), which isGray Scale values, while "U" and "V" represent chroma (chrominance or chroma), which is a description of the imagecolor and saturation for specifying the color of the pixel。 Brightness is created by an RGB input signal by overlaying specific portions of the RGB signal together.Chroma defines two aspects of the color-hue and saturation, which are expressed by CR and CB, respectively .。 Where CR reflects the difference between the red part of the GB input signal and the luminance value of the RGB signal. CB reflects the RGB input signal blue part and RGB signal brightness value of the difference.

In modern color TV system, usually use three-tube color camera or color CCD (point-coupled device) camera, it will take the color image signal, by color, respectively amplification and correction to get RGB, and then through the matrix transformation circuit to obtain the luminance signal Y and two chromatic aberration signal r-y, b-y, The final transmitter encodes three signals of brightness and chromatic aberration, which are sent out using the same channel. This is our usual YUV color space .

YUV (YCRCB) and 4:2:2, 4:1:1, 4:2:0
Refers to the sampling format of the luminance signal Y and the red/blue difference signal. In DV, NTSC is 4:1:1 and PAL uses 4:2:0. Note that the 4:2:0 is not a blue difference signal sample of 0, but compared with 4:1:1, in the horizontal direction to increase the chromatic aberration sampling frequency, in the vertical direction to reduce half of the chromatic aberration sampling in the way of CR/CB interval.

RGB color mode is a color standard of industry, is through the red (R), Green (G), Blue (B) three color channels and their superposition to get a variety of colors, RGB is the red, green, blue three channels of color, This standard almost includes all the colors that human vision can perceive, and is one of the most widely used color systems.
And our computer-related places, is the current display is mostly using the RGB color standards, which is why it is so important to us.
On the display, is through the electronic gun hit on the screen red, green, blue three-color glow to produce color, the current computer generally can display 32-bit color, about 1 million kinds of colors. It is almost impossible for us to tell if the color it displays does not exactly match some of the colors in nature.

RGB is from the color of the principle of light to design, popular Point said its color mix is like red, green, blue three lights, when their light overlap with each other, the color mix, and brightness is equal to the sum of the brightness of the two (two lamp brightness!). ), the higher the blending brightness, the more The addition is mixed.

Coloured light can be diluted and lightened. As the blue light meets the white lights, the result is brighter light blue. Knowing its blending principle, setting the color in the software is easy to understand.

Red, green, blue three lamp overlay, the center of the brightest three-color overlay is white, the addition of mixed features: the more superimposed the brighter.
　　Red, green, blue three color channels each color is divided into 255-order brightness, at 0 o'clock "light" the weakest-is turned off, and in 255 when the "light" the brightest. When the tri-color value is the same as the non-color gray color, and the tri-color is 255 when the brightest white, all 0 is black.

YUV and RGB are two different color spaces . In general, with YUV, you can save storage space, and video codec is advantageous . However, LCD direct reception of the format is basically RGB, in the DSP or similar controller has a dedicated YUV to RGB conversion circuit.

RGB is calculated by the YUV matrix, and its effect is much better than that of S-terminal and CVBs. is currently the main computer monitor video interface (VGA), but after all, still analog signal, so the future mainstream are TMDS (minimum differential signal transmission) Signal DVI interface and HDMI interface . After all, the number is the future, hehe ... Some of these interfaces can be easily converted, so when used we can make the necessary improvements as needed.

There is a difference between YUV and YCbCr. YUV is based on RGB conversion, generally used in traditional TV, YCbCr is based on YUV shift, generally used for digital video

The difference between YUV and RGB in Image color space