ppm2tiff man page
ppm2tiff — create a TIFF file from PPM, PGM and PBM image files
ppm2tiff [ options ] [ input.ppm ] output.tif
ppm2tiff converts a file in the PPM, PGM and PBM image formats to TIFF. By default, the TIFF image is created with data samples packed (PlanarConfiguration=1), compressed with the Packbits algorithm (Compression=32773), and with each strip no more than 8 kilobytes. These characteristics can be overridden, or explicitly specified with the options described below
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.
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.
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.
Mark the resultant image to have the specified X and Y resolution (in dots/inch).
tiffinfo(1), tiffcp(1), tiffmedian(1), libtiff(3)
Libtiff library home page: http://www.simplesystems.org/libtiff/