usage: jpegtran [switches] [inputfile] Switches (names may be abbreviated): -copy none Copy no extra markers from source file -copy comments Copy only comment markers (default) -copy all Copy all extra markers -optimize Optimize Huffman table (smaller file, but slow compression) -progressive Create progressive JPEG file Switches for modifying the image: -crop WxH+X+Y Crop to a rectangular subarea -grayscale Reduce to grayscale (omit color data) -flip [horizontal|vertical] Mirror image (left-right or top-bottom) -perfect Fail if there is non-transformable edge blocks -rotate [90|180|270] Rotate image (degrees clockwise) -transpose Transpose image -transverse Transverse transpose image -trim Drop non-transformable edge blocks Switches for advanced users: -arithmetic Use arithmetic coding -restart N Set restart interval in rows, or in blocks with B -maxmemory N Maximum memory to use (in kbytes) -outfile name Specify name for output file -verbose or -debug Emit debug output -version Print version information and exit Switches for wizards: -scans file Create multi-scan JPEG per script file