Convert PNM to PPM

The PNM (Portable Anymap) file extension, developed by Jef Poskanzer in the 1980s, stands for Portable Any Map. It is an uncompressed raster graphics format designed for portable image storage and exchange, encompassing three sub-formats: PBM (Portable Bitmap), PGM (Portable Graymap), and PPM (Portable Pixmap). PNM files store image data in plain text or binary format, ensuring easy usage across different platforms and applications. This format is widely supported by various image editing software and is valued for its simplicity and lossless compression.

The Portable Pixmap (PPM) file extension, an image format within the Netpbm family, stores simple, uncompressed images. Introduced in the late 1980s, PPM supports RGB color and grayscale images, making it suitable for basic image processing and conversion tasks. Its plain text encoding simplifies debugging and data manipulation, although its lack of compression results in larger file sizes compared to modern formats. As such, PPM finds limited use in contemporary applications, mainly in educational and experimental settings where ease of implementation and readability are prioritized.