Chroma Subsampling

Chroma subsampling

Chroma subsampling is a technique that reduces the amount of data required to represent color in digital images. It’s similar to compression algorithms used in formats like JPEG, but it’s optimized for video, where every bit counts. When you see your favorite movie or TV show on DVD or Blu-Ray, the colors you’re seeing are actually represented as only half of what they should be!

What Is Chroma Subsampling?

Chroma subsampling is the process of reducing the resolution of chroma channels in digital video. It reduces bandwidth and storage requirements since the human eye only processes color information at about a third of luminance. Essentially, you can sample color information at a lower resolution while keeping good image quality.

Cat Image Chroma Subsampling

Here you can see the image with the lowest quality with Chroma Subsampling.

The term “chroma” refers to color information separate from luma or luminance (black-and-white). So when you’re watching a movie on your TV or computer monitor and see a rainbow pattern around text characters like this one, that means there are four different types of video being displayed at once:

  • Reds/greens/blues (the “C”)
  • Blacks/whites (“Y”) make up what we call brightness or luminance
  • Reds/greens/blues again — but now without any black or white pixels mixed in so we can see only pure colors instead
  • Finally, another set consisting solely of black pixels but with various shades depending on how dark each one gets compared with its neighbors

How Does Chroma Subsampling Work?

Chroma subsampling is a technique used to reduce the amount of data needed to store or transmit video signals. It works by reducing the resolution of chroma (color) information in an image while keeping luma (luminance) intact.

It’s used in digital TV, Blu-ray, and DVD formats, and AVC/H.264 compression standards for HDTV broadcasting. Internet streaming applications such as Netflix or YouTube videos encoded at 4K resolutions also utilize this for better quality when streaming over WiFi and LTE networks.

Add Chroma Subsampling with Cloudinary

Cloudinary offers chroma subsampling through our Media Optimization. With it, you can easily toggle chroma subsampling on and off. To get started with Cloudinary and get your media up to modern standards, you can sign up for free today!

Last updated: May 25, 2023