The libjpeg package contains cjpeg, djpeg, jpegtran, rdjpgcom, wrjpgcom and jpeg libraries. cjpeg compresses image files to produce a JPEG/JFIF file on the standard output. Currently supported input file formats are: PPM (PBMPLUS color format), PGM (PBMPLUS gray-scale format), BMP, and Targa. djpeg decompresses image files from JPEG/JFIF format to either PPM (PBMPLUS color format), PGM (PBMPLUS gray-scale format), BMP, or Targa format. jpegtran is used for lossless transformation of JPEG files. rdjpgcom displays text comments from within a JPEG file. wrjpgcom inserts text comments into a JPEG file. These libraries are used by many programs for reading and writing jpeg format files.