If the PPM file contains greyscale data, then the PhotometricInterpretation tag is set to 1 (min-is-black), otherwise it is set to 2 (RGB).
If no PPM file is specified on the command line, ppm2tiff will read from the standard input.
|-c||Specify a compression scheme to use when writing image data: none for no compression, packbits for PackBits compression (will be used by default), lzw for Lempel-Ziv & Welch compression, jpeg for baseline JPEG compression, zip for Deflate compression, g3 for CCITT Group 3 (T.4) compression, and g4 for CCITT Group 4 (T.6) compression.|
|-r||Write data with a specified number of rows per strip; by default the number of rows/strip is selected so that each strip is approximately 8 kilobytes.|
|-R||Mark the resultant image to have the specified X and Y resolution (in dots/inch).|