Nice that you guys cleared that up
The reason this system is chosen, is probably because of some high-experienced staff inside Realtek.
From Wikipedia "FELICS, which stands for Fast Efficient & Lossless Image Compression System, is a lossless image compression algorithm that performs 5-times faster than the original lossless JPEG codec and achieves a similar compression ratio."
This is an OLD way of compression and rather something i would see in older technology like a Super Nintendo rom, or Arcade game machine system from that era. It is highly effective though, and i can understand why speed was chosen over the 5-times slower JPEG performance. It also seems there is no patent filed on it, and no royalties required. Perhaps that was also a reason to choose it