From the article: "Mozilla did a study of various lossy compressed image formats. HEVC (hence BPG) was a clear winner by a wide margin. BPG files are actually a

From the article: "Mozilla did a study of various lossy compressed image formats. HEVC (hence BPG) was a clear winner by a wide margin. BPG files are actually a little smaller than raw HEVC files because the BPG header is smaller than the corresponding HEVC header." This study includes WebP.