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Ppmdither User Manual(0) Ppmdither User Manual(0)NAMEppmdither - ordered dither for color imagesSYNOPSISppmdither[-dimpower] [-redshades] [-greenshades] [-blueshades] [ppmfile]DESCRIPTIONThis program is part of Netpbm(1).ppmditherreads a PPM image as input, and applies dithering to it to reduce the number of colors used down to the specified number of shades for each primary. The default number of shades is red=5, green=9, blue=5, for a total of 225 colors. To convert the image to a binary rgb format suitable for color printers, use -red 2 -green 2 -blue 2. You can do another kind of dither -- Floyd-Steinberg -- withpnmquantorpnmremap.OPTIONS-dimpowerThe size of the dithering matrix. The dithering matrix is a square whose dimension is a power of 2.poweris that power of 2. The default is 4, for a 16 by 16 matrix.-redshadesThe number of red shades to be used, including black; minimum of 2.-greenshadesThe number of green shades to be used, including black; minimum of 2.-blueshadesThe number of blue shades to be used, including black; minimum of 2.SEEALSOpamdepth(1), pnmquant(1), pnmremap(1), ppm(1)AUTHORCopyright (C) 1991 by Christos Zoulas. netpbm documentation 14 July 1991 Ppmdither User Manual(0)