The Lenna (or Lena) picture is one of the most widely used standard test images used for compression algorithms.'lena' or 'lenna' is a digitized Playboy centerfold, from November 1972. (Lenna is the spelling in Playboy, Lena is the Swedish spelling of the name.) Lena Soderberg (ne Sjööblom)
The Portable Network Graphics (PNG) is a format for storing compressed raster graphics. The compression engine is based on the Deflate method [RFC1951], designed by PKWare and originally used in PKZIP.
the compression tool with unbelievable high compression rate. It surpasses even such efficient compression tool like 7zip and UHARC in terms of the abilities.(special hardware needs)