How to use the command pnmtoxwd (with examples)

The pnmtoxwd command is used to convert a PNM (Portable Any Map) file into an X11 window dump (XWD) file. It is a part of the Netpbm package and can be used to convert PNM images into a format that can be displayed on an X11 server.

Use case 1: Convert a PNM image file to XWD

Code:

pnmtoxwd path/to/input_file.pnm > path/to/output_file.xwd

Motivation: This use case is useful when you have a PNM image file and want to convert it into an XWD file. XWD files are binary files that can be displayed on an X11 server. Converting the PNM image into XWD format allows you to view it using programs that can open XWD files.

Explanation:

• pnmtoxwd is the command to convert a PNM file to XWD.
• path/to/input_file.pnm is the path to the input PNM file that you want to convert.
• path/to/output_file.xwd is the path to the output XWD file that will be created after the conversion.

Example output: The PNM image file will be converted to XWD format and saved as the specified output file. You can then use any program that supports XWD files to view the image.

Use case 2: Produce the output in the DirectColor format

Code:

pnmtoxwd -directcolor path/to/input_file.pnm > path/to/output_file.xwd

Motivation: The DirectColor format is a color format that improves the color representation in XWD files. If you want to have a better color representation in the output XWD file, you can use the -directcolor option to produce the output in DirectColor format.

Explanation:

• -directcolor is the option used to produce the output in DirectColor format.
• path/to/input_file.pnm is the path to the input PNM file that you want to convert.
• path/to/output_file.xwd is the path to the output XWD file that will be created after the conversion.

Example output: The PNM image file will be converted to XWD format using DirectColor. The output XWD file will have improved color representation compared to the default format.

Use case 3: Set the color depth of the output to b bits

Code:

pnmtoxwd -pseudodepth b path/to/input_file.pnm > path/to/output_file.xwd

Motivation: Setting the color depth of the output XWD file allows you to control the number of bits used to represent each color in the image. This can be useful if you want to optimize the file size or have specific requirements for the color depth.

Explanation:

• -pseudodepth b is the option used to set the color depth of the output XWD file to b bits. Replace ‘b’ with the desired number of bits.
• path/to/input_file.pnm is the path to the input PNM file that you want to convert.
• path/to/output_file.xwd is the path to the output XWD file that will be created after the conversion.

Example output: The PNM image file will be converted to XWD format with the specified color depth. The output XWD file will use the specified number of bits to represent each color in the image.

Conclusion:

The pnmtoxwd command is a useful tool for converting PNM files into XWD files. It provides various options to customize the output format, color representation, and color depth of the resulting XWD file. By leveraging these options, you can convert PNM images into XWD format that best suits your requirements.