Difference between YUV420 and YUV422

image-processing, yuv

Solution

4:2:2: The two chroma components are sampled at half the sample rate of luma: the horizontal chroma resolution is halved.

4:2:0: The two chroma components are sampled at half the sample rate of luma both horizontally and vertically (i.e. there's one `U` and one `V` per 2x2 group of `Y`s).

For info regarding other variations, see this, this and this.

Problem

Can you please help me understand what are the differences between YUV420 and YUV422 format? I read this, http://www.fourcc.org/yuv.php, but I can't find the difference. And does "YUV420" and "YUV420 SP" mean the same thing? And does "YUV422" and "YUV422 I" mean the samet thing? Thank you.

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