Free Online EPUB to G4 Converter

Is a format developed by the International Digital Publishing Forum. It is characterized by the XML- and XHTM-based optional use of CSS styling. The main feature of this format is the use of reflowable text (word wrap) which makes it possible to adapt the image to different device displays. The ePub file is a zip-archive with an .epub extension.

G4 is a method to compress black and white images without losing quality. It is used for fax machines and as a one of the compression types for the TIFF format. G4 treats a picture as black dots and lines on a white page (less file size will be achieved if there are less black dots and lines).