Convert PBM to G4

The PBM (Portable Bitmap) file extension, part of the Netpbm project, originated in the late 1980s to facilitate efficient and portable graphics file interchange. Primarily, PBM files are used to store monochrome bitmaps in a simple ASCII text format, ensuring easy compatibility across different systems and platforms. This format supports only black-and-white imagery, making it particularly useful in scenarios where simplicity and minimalism are prioritized, such as in Unix environments for bitmap manipulation and transfer. Its historical significance lies in promoting a standardized approach to bitmap graphics in early computer technology.

The G4 file extension, standing for CCITT Group 4 Fax Image, is a specialized format used primarily for storing black-and-white facsimile (fax) images. Its origins trace back to the Consultative Committee for International Telegraphy and Telephony (CCITT), now known as the ITU-T, which developed the Group 4 standard in the 1980s to improve fax transmission efficiency over digital networks. This format employs a high compression ratio to reduce file size while maintaining image quality, making it ideal for archiving documents and transmitting faxes in professional and business environments.