Discrete cosine transform

Discrete cosine transform is a fancy way of changing a bunch of numbers into a new set of numbers that show us how much of each kind of pattern is in our group of numbers.

Imagine you have a bag of different colored marbles. You want to know how many of each color you have, but it would be confusing to count them all separately. So, you sort the marbles by color and count how many of each color you have. This is how DCT works - it sorts the numbers in a group and shows us how much of each kind of pattern, or "color", there is.

DCT is particularly useful in image and audio compression because it groups similar patterns or colors, allows for easier storage and transmission, and can reduce the amount of data needed to represent the image or sound file.

So, in summary, DCT is a method of analyzing a set of numbers to see how much of each pattern or color is present, making it easier to store and transmit the data in a compressed format.