Why does the Y component in YCbCr represent luma/intensity?

1. What does YCbCr stand for?
2. Why convert RGB to YCbCr?
3. What is the difference between YUV and YCbCr?
4. How do you convert YCbCr to RGB?

What does YCbCr stand for?

YCbCr, Y′CbCr, or Y Pb/Cb Pr/Cr, also written as YC_BC_R or Y′C_BC_R, is a family of color spaces used as a part of the color image pipeline in video and digital photography systems. Y′ is the luma component and C_B and C_R are the blue-difference and red-difference chroma components.

Why convert RGB to YCbCr?

Image and Video consumes a lot of data. One of the reasons is because they are represented in the RGB format. However, is not worth to store or transmit information in this color space representaion, once it has a large bandwidth. Thus all the pixels should be converted to YCbCr to accomplish that.

What is the difference between YUV and YCbCr?

YUV is an analog system. YCbCr is a digital system and widely used in video compression e.g. MPEG2. The range of RGB is 0.. 255 e.g. R value can be from 0 – 255.

How do you convert YCbCr to RGB?

YCbCr to RGB conversion is typically done using GPU shaders so the 0-255 YCbCr values are automatically converted into 0.0-1.0 range floats (ie gpuY = Y / 255). This doesn't affect the multiplication numbers but the offset numbers need to be divided by 255.