This video is talking about Chroma Subsampling. To be honest, I wasn’t aware of this until I saw this. Hope you find it intresting.
What we’re talking about here is called Chroma Subsampling, and if your eyes glaze over when you hear that, you’re not alone. There’s a LOT of confusion about this topic, and most of it stems from the fact that there have been two different approaches to chroma subsampling, and both of them are written out the same way: 4:x:x. However, I’m only going to cover the more modern and prevalent system.
Let’s start at the beginning. An electronic image is composed of little squares called pixels. Each pixel can have luminance – luma – which tells the pixel how bright or dark to be, and chrominance – chroma – which tells the pixel what color to be. If you don’t have any chroma data, your image will be grayscale – black and white. But if you don’t have any luma data, you won’t have any image at all.