cmuwmtopbm

Convert a CMU window manager bitmap to a PBM image

$ cmuwmtopbm [path/to/image.pbm] > [path/to/output.bmp]

cmuwmtopbm [cmuwm-bitmapfile]

cmuwmtopbm is a specialized utility included in the Netpbm suite of graphic conversion tools. Its primary function is to convert image files stored in the proprietary CMU window manager bitmap format into the standard Portable BitMap (PBM) format.

The CMU window manager bitmap format was specific to the CMU Window Manager, an early and now largely historical window manager developed at Carnegie Mellon University for the X Window System. The PBM format, on the other hand, is a very simple, 1-bit (black and white) image format, part of the Netpbm family, widely supported by various image processing applications.

This command is particularly useful for handling legacy image data originating from the CMU window manager environment, enabling users to view, manipulate, or integrate these historical bitmaps with modern image tools that support Netpbm formats. By default, cmuwmtopbm reads the CMU bitmap data from standard input; however, a specific input file can be provided as an argument. The converted PBM image is always written to standard output, allowing for easy piping with other Netpbm utilities or redirection to a file.

This tool is highly specialized for a legacy bitmap format. Its primary utility lies in converting historical data from the CMU Window Manager environment, which is largely obsolete. It is unlikely to be needed for contemporary image processing tasks unless dealing with specific legacy assets.

By default, cmuwmtopbm reads the CMU bitmap from standard input. If a file path is provided as an argument, it reads from that specified file instead. The resulting PBM image is always written to standard output. This design allows for flexible use in shell pipelines, enabling seamless integration with other Netpbm tools or redirection of the output to a file.

cmuwmtopbm is part of the Netpbm project, a collection of graphic conversion tools that originated from Jef Poskanzer's Pbmplus package in the late 1980s and early 1990s. The command was developed to address the need for interoperability between the specific bitmap format used by the early CMU Window Manager and the more universal Netpbm image processing ecosystem. Its existence highlights a period in computing when many bespoke graphic formats existed, and tools like Netpbm were crucial for format translation and interoperability.

pbm(5), netpbm(1), xbmtopbm(1), bmptopbm(1)