Get the latest tech news
Do grayscale images take less space?
Grayscale Images Take Less Space? TL;DR Grayscale images usually take less space than those represented in the more common sRGB space. However, subsampling and optimizations applied on chroma (colors) channels can be so aggressive (without visual impact) that a 4:2:0-subsampled image is sometimes pretty close to a grayscale image in terms of size.
JPEG/JFIF (and other common formats) doesn't process pixels encoded as RGB triples directly. This property is exploited to reduce image file size without unacceptable visual degradation thanks to a simple, yet effective technique: subsampling. That is, a grayscale image encoded in JPEG contains the only channel that left not much room for aggressive optimization.
Or read this on Hacker News
