Convert PGM to ICB

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.

The ICB file extension, associated with Targa Graphics, stands for Image Capture Board. It was originally used with the AT&T EPICenter Image Capture Board video card and software like ICB-PAINT and TARGA-PAINT. This format is a raster graphics file used for storing and exchanging deep-pixel images, supporting 8, 16, 24, and 32 bits per pixel. Developed by Truevision Inc., it played a significant role in early computer graphics for high-color display on IBM-compatible PCs.