Convert RAD to PPM

The RAD file extension, associated with the Radiance software suite, stands for Radiance Scene Description. It is used to describe materials and geometry for lighting simulations and rendering programs. Developed by Greg Ward at Lawrence Berkeley National Laboratory, Radiance employs ray tracing and an octree data structure for accurate lighting calculations. RAD files are ASCII text files that must be compiled into an octree before rendering.

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.