What does it mean that photography is in jpc format?

This is not JPC format, but JPG format.

If you use SLR photography, there are two storage formats, one is JPG format, and the photos in this format are compressed by the CPU inside the SLR camera. Photos can be used directly, but they can't be edited later. This is called direct filming.

The other format is RAW format, which faithfully records the original information of photos without any processing. The photos in this format should be post-processed by professional processing software on the computer later, which can correct the shortcomings of the photos and achieve the best results, but the processing of this photo format requires professional knowledge.

The main photography adopts RAW format. The so-called "three-point photography and seven-point post-processing" is to shoot in this format and then post-process it on the computer.