An RGB image file, like those used by Corsetti in his analysis, is comprised of a series of data bytes. Three bytes - one red, one green and one blue - represent each pixel in the image. The numerical values of the bytes indicate the color of the pixel.When gzip compresses a file, it looks for multi-byte patterns in the data. It assigns a number to each pattern it finds and maintains a table that pairs patterns with their corresponding numbers. Each time a pattern recurs in the original file, instead of storing the pattern, the compressed file stores the number that represents the pattern. In this way, a pattern tens or even hundreds of bytes long can be represented by a number that is one, two or three bytes long. This is why the compressed file is smaller.Corsetti explains that the biogenic images are more compressible because theyre more predictable or redundant, which can be considered a form of biologic complexity.
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