How does the program recognize graphics files?
How does the program recognize graphics files (images or photos)?
Usually graphics files have unique attributes at the beginning of the file. It's enough to read several bits of the file to tell for sure that this file is a JPEG file.
Also, there are graphics file formats without any unique attributes, for example RAW format. In this case one can recognize this file by extension only.
Image Converter Plus recognizes graphics files in both ways.