# xwdtopnm - man(1) - [phpMan] > **TLDR:** Convert an X11 or X10 window dump file to PNM. > - Convert a XWD image file to PBM: `xwdtopnm {{path/to/input_file.xwd}} > {{path/to/output_file.pnm}}` - Display information about the conversion process: `xwdtopnm {{-verb|-verbose}} {{path/to/input_file.xwd}} > {{path/to/output_file.pnm}}` - Display the contents of the X11 header of the input file: `xwdtopnm {{-h|-headerdump}} {{path/to/input_file.xwd}} > {{path/to/output_file.pnm}}` *Source: tldr-pages* --- _Xwdtopnm_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown) General Commands Manual _Xwdtopnm_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown) ## NAME xwdtopnm - convert an X11 or X10 window dump file to a PNM image ## SYNOPSIS **xwdtopnm **[**-verbose**] [**-headerdump**] [_xwdfile_] ## DESCRIPTION This program is part of [**Netpbm**(1)](https://www.chedong.com/phpMan.php/man/Netpbm/1/markdown). **xwdtopnm **reads an X11 or X10 window dump file as input and produces a PNM image as output. The type of the output image depends on the input file - if it's black and white, the output is PBM. If it's grayscale, the output is PGM. Otherwise, it's PPM. The program tells you which type it is writing. Using this program, you can convert anything you can display on an X workstation's screen into a PNM image. Just display whatever you're interested in, run the **xwd **program to capture the contents of the window, run it through **xwdtopnm**, and then use **pamcut **to select the part you want. Note that a pseudocolor XWD image (typically what you get when you make a dump of a pseudo‐ color X window) has maxval 65535, which means the PNM file that **xwdtopnm **generates has maxval 65535. Many older image processing programs (that aren't part of the Netpbm package and don't use the Netpbm programming library) don't know how to handle a PNM image with maxval greater than 255 (because there are two bytes instead of one for each sample in the image). So you may want to run the output of **xwdtopnm **through **pamdepth **before feeding it to one of these old programs. **xwdtopnm **can't convert every kind of XWD image (which essentially means it can't convert an XWD created from every kind of X display configuration). In particular, it cannot convert one with more than 24 bits per pixel. ## OPTIONS In addition to the options common to all programs based on libnetpbm (most notably **-quiet**, see [ Common Options](index.html#commonoptions) ), **xwdtopnm **recognizes the following command line options: ### -verbose This option causes **xwdtopnm **to display handy information about the input image and the conversion process ### -headerdump This option causes **xwdtopnm **to display the contents of the X11 header. It has no ef‐ fect when the input is X10. This option was new in Netpbm 10.26 (December 2004). ## NOTES ### Two Byte Samples **xwdtopnm **sometimes produces output with a maxval greater than 255, which means the maximum value of a sample (one intensity value, e.g. the red component of a pixel) is greater than 255 and therefore each sample takes 2 bytes to represent. This can be a problem because some programs expect those bytes in a different order from what the Netpbm format specs say, which is what **xwdtopnm **produces, which means they will see totally different colors than they should. **xv **is one such program. If this is a problem (e.g. you want to look at the output of **xwdtopnm **with **xv**), there are two ways to fix it: • Pass the output through **pamendian **to produce the format the program expects. • Pass the output through **pamdepth **to reduce the maxval below 256 so there is only one byte per sample. Often, there is no good reason to have a maxval greater than 255. It happens because in XWD, but not PNM, each color component of a pixel can have different resolution, for example 5 bits for blue (maxval 31), 5 bits for red (maxval 31), and 6 bits for green (maxval 63), for a total of 16 bits per pixel. In order to reproduce the colors as closely as possible, **xwd‐** **topnm **has to use a large maxval. In this example, it would use 31 * 63 = 1953, and use 48 bits per pixel. Because this is a common and frustrating problem when using **xwdtopnm**, the program issues a warning whenever it generates output with two byte samples. You can quiet this warning with the **-quiet **[common option](index.html#commonoptions) . The warning was new in Netpbm 10.46 (March 2009). ## SEE ALSO [**pnmtoxwd**(1)](https://www.chedong.com/phpMan.php/man/pnmtoxwd/1/markdown), [**pamendian**(1)](https://www.chedong.com/phpMan.php/man/pamendian/1/markdown), [**pamdepth**(1)](https://www.chedong.com/phpMan.php/man/pamdepth/1/markdown), [**pnm**(1)](https://www.chedong.com/phpMan.php/man/pnm/1/markdown), **xwd **man page ## AUTHOR Copyright (C) 1989, 1991 by Jef Poskanzer. ## DOCUMENT SOURCE This manual page was generated by the Netpbm tool 'makeman' from HTML source. The master documentation is at **** netpbm documentation 08 January 2010 _Xwdtopnm_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)