Can you confirm that your VeryPDF PDF to Image Converter, can convert PDF's to a .CAL format? See below for details on .CAL format;
The CALS Raster File Format is a bitmap defined by the U.S. Department of Defense and intended for storing monochrome images.
There are two types of CALS files:
1. Type 1: Stores a single image per file and data is always compressed using CCITT Group 4.
2. Type 2: Can store multiple images per file, the image data for each image can be subdivided into tiles, and each tile can be stored uncompressed, or compressed using CCITT Group 4.
Thanks for your message, VeryPDF PDF to Image Converter can't convert PDF file to CAL format, however, we will try to support CAL format in the future, thank you.