NAME

       pamtowinicon - convert Netpbm PAM images to a Microsoft Windows icon file

SYNOPSIS

       pamtowinicon [-pngthreshold=threshold] [-truetransparent] [-verbose] [pam_file]

       All  options  can be abbreviated to their shortest unique prefix.  You may use two hyphens instead of one
       to designate an option.  You may use either white space or equals signs between an option  name  and  its
       value.

DESCRIPTION

       This program is part of Netpbm(1).

       pamtowinicon reads an RGB_ALPHA Netpbm PAM file and converts it to a Microsoft Windows icon file.

       The output goes to Standard Output.

       The  input  is  a multi-image PAM file; each image becomes an icon in the output file.  If you have input
       images in multiple files, you can simply combine them with cat and pass the result to pamtowinicon.

OPTIONS

       In addition to the options common to all programs based on libnetpbm (most  notably  -quiet,  see  Common
       Options ), pamtowinicon recognizes the following command line options:

       -pngthreshold=threshold
              pamtowinicon  encodes  images  with  resolutions  above  or equal threshold by threshold as PNG by
              running pnmtopng(1).  Other images it encodes using the more traditional BMP format.

              When the program uses PNG encoding for a 5-channel PAM with separate  AND  mask  (see  below),  it
              discards  the  AND  mask.   Because  PNG  has  always had the ability to specify transparency, the
              Windows icon format does not provide for a separate and mask when the icon is encoded in PNG.

              The default value for threshold is 128.

       -truetransparent
              Make all pixels outside the opaque area  black,  avoiding  inversion  and  other  effects  on  the
              background of the image (see Windows Icons(1)).

       -verbose
              Print more messages

IMAGES

       pamtowinicon  reads  a  (multi-image)  Netpbm  PAM  file as input and outputs an single Windows icon file
       containing those images.

       The images in the icon file are in the same order as in the PAM input.

   PAM Input
       pamtowinicon interprets the PAM images as follows, based on the number of channels.

       ────────────────────────────────────────────────────────────────────
       channels   image
       1          fully opaque grayscale image
       2          grayscale image with transparency channel
       3          fully opaque color image
       4          color image with transparency channel
       5          color image with transparency channel and additional AND
       mask

       The tuple types of the PAMs are irrelevant.

   AND Mask
       The so-called "AND mask" is a special feature of Microsoft Windows icons.  It is  required  for  all  BMP
       encoded  images.   At  the first sight, the AND mask is a 1-bit transparency channel, but it is also used
       for e.g. shading the icon while dragging.  See Windows Icons(1) for details.

       If there is no explicit AND mask, but transparency data in the input image,  pamtowinicon  sets  the  AND
       mask  to  opaque  where  the  sample  in  the  transparency  channel  is below maxval, and to transparent
       elsewhere.

       If no transparency data is present in the input image, pamtowinicon assumes the whole image to  be  fully
       opaque.

   BMP Output
       When  BMP  encoding  an  image, pamtowinicon tries to use the most compact BI_RGB format allowed for icon
       images with a color depth of eight bits per channel.

       pamtowinicon generates neither 16-bit BI_RGB nor BI_BITFIELDS BMP encoded images, even if the  maxval  of
       the input PAM is not 255.

SEE ALSO

       •      winicontopam(1)

       •      ppmtowinicon(1)

       •      pam(1)

       •      Windows Icons(1)

       For information on the PNG format, see http://schaik.com/png .

HISTORY

       pamtowinicon  was  new in Netpbm 10.63 (June 2013).  It obsoleted ppmtowinicon by providing more function
       and conforming better to Netpbm conventions.

AUTHOR

       Copyright (C) 2013 by Ludolf Holzheid.

       Translated to Netpbm coding style by Bryan Henderson.

DOCUMENT SOURCE

       This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The  master  documentation
       is at

              http://netpbm.sourceforge.net/doc/pamtowinicon.html

netpbm documentation                              12 April 2013                      Pamtowinicon User Manual(1)