Convert HPGL to CAL

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 CAL file extension, known as CALS (Continuous Acquisition and Life-cycle Support) Type 1 Image, is a 1-bit black-and-white raster image format developed by the U.S. Department of Defense in the mid-1980s to standardize graphics data interchange for military documentation. It is primarily used for storing and sharing monochrome images while retaining orientation metadata. The format supports both uncompressed and compressed (using CCITT Group 4 compression) images.