"cjpeg" is the basic command-line tool for making use of the mozjpeg library to create JPEG images. libjpeg-turbo and IJG JPEG libraries also have "cjpeg" tool

"cjpeg" is the basic command-line tool for making use of the mozjpeg library to create JPEG images. libjpeg-turbo and IJG JPEG libraries also have "cjpeg" tools as their basic command-line encoder. The tool for mozjpeg works almost exactly the same way, but it has some extra option flags, can take JPEG input (the others can't), and re-defines the "-baseline" option to something more intuitive (see v2.1 release notes).