How to use the command pnmscale (with examples)

The pnmscale command is a command-line tool that was used to scale images in the Portable Bitmap (PBM), Portable Graymap (PGM), and Portable Pixelmap (PPM) formats. However, it has been replaced by the pamscale command. The pamscale command is part of the Netpbm package and provides more advanced features for image scaling.

Use case 1: View documentation for pamscale

Code:

tldr pamscale

Motivation: This use case is useful when you need a quick reference guide for the pamscale command. The tldr command provides concise and easy-to-understand examples and explanations of various commands, including pamscale. By using tldr pamscale, you can quickly access the basic usage and options of the pamscale command.

Explanation:

• tldr is a command-line tool that stands for “Too Long; Didn’t Read”. It provides simplified and practical examples of various terminal commands.
• pamscale is the specific command for which you want to view the documentation.

Example output:

pamscale - Scale Netpbm image files.

  pamscale [-reduce scale-factor] [-enlarge scale-factor] [pamfile]

  -pamfile       Width, height, or both may be specified as '0' - this
                 means to write the final image to standard output.
          
                 You may specify a format keyword instead of the filename.
                 "pnm" (the default) is the portable arbitrary width
                 pixmap, PGM is plain graymap, PPM is plain pixmap, and any
                 other string that starts with p and ends in m and has
                 nothing but letters and numbers in between is the
                 corresponding binary format.
  
...

Conclusion:

In this article, we explored the pnmscale command and learned how it has been replaced by the pamscale command. We also discussed a use case for viewing the documentation of pamscale using the tldr command. It is recommended to use pamscale instead of pnmscale for more advanced image scaling capabilities.