Pamdepth User Manual(0)				       Pamdepth User Manual(0)



NAME
       pamdepth - change the maxval in a Netpbm image


SYNOPSIS
       pamdepth newmaxval [netpbmfile]


DESCRIPTION
       This program is part of Netpbm(1).

       pamdepth	 reads	a  Netpbm image as input, scales all the pixel values,
       and writes out the image with the new maxval.  Scaling the colors  down
       to a smaller maxval will result in some loss of information.

       This program works on multi-image streams.

       Be  careful  of	off-by-one  errors  when choosing the new maxval.  For
       instance, if you want the color values to be five bits wide, use a max-
       val of 31, not 32.

       One  important  use  of pamdepth is to convert a new format 2-byte-per-
       sample PNM file to the older 1-byte-per-sample  format.	 Before	 April
       2000,  essentially  all raw (binary) format PNM files had a maxval less
       than 256 and one byte per sample, and many programs may rely  on	 that.
       If  you specify a newmaxval less than 256, the resulting file should be
       readable by any program that worked with PNM files before April 2000.


SEE ALSO
       pnm(1), pam(1), pnmquant(1), ppmdither(1) ppmbrighten(1) pamfunc(1)


HISTORY
       pamdepth	 was  new  in  Netpbm  10.32  (February	 2006).	  It  replaced
       pnmdepth,  by  Jef  Poskanzer.	pamdepth  is  backward compatible with
       pnmdepth and adds the ability to process arbitrary PAM images  and  the
       ability	to  process  multi-image input streams.	 pnmdepth handled only
       PNM images and ignored all but the the first in any stream.



netpbm documentation		 08 April 2000	       Pamdepth User Manual(0)