Convert SUN to PGM

The Sun Raster (SUN) file extension, originating from Sun Microsystems, is a bitmap image format used primarily on SunOS systems. Known for its versatility in storing raster graphics, it supports various color depths, from monochrome to 24-bit true color. Initially created for the Sun workstation's image processing software, it facilitated efficient graphical data manipulation and transmission. Over time, its straightforward structure and compatibility with different Unix-based systems ensured its adoption in diverse graphic applications. Today, while largely historical, the SUN file format remains an important part of the legacy of early computer graphics development.

The Portable Graymap (PGM) file extension, originating in the late 1980s as part of the Netpbm project, stands for "Portable Gray Map". It serves as a simple, versatile format for grayscale images, enabling easy reading and writing by various programs. Due to its straightforward structure and plain text encoding, it's often used in academic and research settings where ease of parsing and accessibility are crucial. PGM files store grayscale images in a compact, efficient manner, making them an essential tool for image processing tasks.