Minimum unique abbreviation of options is acceptable. You may use double hyphens instead of single hyphen to denote options.
This program is part of Netpbm.
The pamwipeout utility takes a Neptbm image as input and the uses two opposite edges of the image to wipe out anything in between. You can use it in combination with pamcut and pnmpaste / pamcomp to remove unwanted parts of a larger image. The program replaces the pixels in between the two edges with a gradient from one edge to the other.
In top-bottom mode, the program reads the whole image into memory before it can start processing. In left-right it will read the image a row at the time, process that row and write it to the output file. Therefore, in case of very large images, it may be better to use instead of "pamwipeout -tb" a pipe of "pamflip -cw | pamwipeout -lr | pamflip -ccw".
In his blog at www.i-am.ws, the author wrote about a predecessor of "pamwipeout" at the time named "pnmblend". It shows a good example of what can be accomplished with this utility.
Filename is the name of the input file. If you don't specify this, pamwipeout reads the image from Standard Input.
This option chooses between a vertical and a horizontal gradient. You must specify one of these, but not both.
pamwipeout was new in Netpbm 10.54 (March 2011).
Willem van Schaik wrote this program in January 2011 and contributed it to Netpbm.