Convert JNG to G3

The JPEG Network Graphics (JNG) file extension is designed for storing JPEG-encoded image data within the PNG file format. Introduced as part of the MNG (Multiple-image Network Graphics) format, JNG was created to provide a flexible, high-quality image format that supports both lossy and lossless compression. It is particularly useful in applications requiring the integration of JPEG compression within a wider range of data types and multimedia elements. Though not widely adopted, JNG offers enhanced compatibility and versatility for complex imaging tasks in computer graphics and web development.

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.