Convert G4 to VIPS

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.

The VIPS (Virtual Image Processing System) file format, developed by the libvips library, is designed for high-performance image processing with low memory usage. It supports arbitrary metadata and is optimized for command-line operations. Although not widely supported by other programs, it serves as an efficient intermediate format for tasks like image inversion and gamma correction. The format includes a 64-byte header with basic fields such as image width and a set of band-interleaved scanlines for the image data.