Convert HPGL to G3

The HPGL file extension, short for Hewlett-Packard Graphics Language, is a file format and printer control language developed by Hewlett-Packard in 1977 for use with their plotter printers, starting with the HP-9872. HPGL files contain commands that instruct plotters to draw images using lines rather than dots, making them essential in CAD applications and technical drawings. The language uses a series of two-letter codes followed by parameters to control the plotter's actions, such as moving the pen or drawing shapes.

The G3 file extension refers to the CCITT Group 3 Fax Image, a standardized format developed by the Consultative Committee for International Telegraphy and Telephony (CCITT), now known as ITU-T. This format was created to efficiently compress black-and-white fax documents for transmission over telephone lines. It employs a method called Modified Huffman Coding for data compression, enabling reduced transmission time and bandwidth usage. G3 was widely adopted in the 1980s and 1990s as the primary standard for fax transmissions, ensuring compatibility across different fax machines and systems.