ximtoppm(1) convert an Xim file into a portable pixmap


ximtoppm [--alphaout={alpha-filename,-}] [ximfile]


ximtoppm creates a PGM (portable graymap) file containing the alpha channel values in the input image. If the input image doesn't contain an alpha channel, the alpha-filename file contains all zero (transparent) alpha values. If you don't specify --alphaout, ximtoppm does not generate an alpha file, and if the input image has an alpha channel, ximtoppm simply discards it.

If you specify - as the filename, ximtoppm writes the alpha output to Standard Output and discards the image.

Actually, an Xim image can contain an arbitrary fourth channel -- it need not be an Alpha channel. ximtoppm extracts any fourth channel it finds as described above; it doesn't matter if it is an alpha channel or not.

See pnmcomp(1) for one way to use the alpha output file.

All options can be abbreviated to their shortest unique prefix.


Copyright (C) 1991 by Jef Poskanzer.