Hilbert Curve in Cryptography?!

Hilbert curve, named after its inventor David Hilbert, is one of the most popular fractals in Mathematics. It is known for its ability to arise from the first dimension to higher dimensions through executing a set of recurring actions. The simplistic curve has numerous applications in reality, one of which is to encrypt images. Chaos cryptologists Xuncai Zhang et. al. propose an image encryption scheme using Hilbert curve and experiment with the proposed scheme. Precisely, the Hilbert curve is used to string up all pixel points in the picture and provide a new order to the image. A chaos system PWLCM system, SHA-3, and H-fractal are used in addition to the Hilbert curve in order to provide global disturbance and increase the complexity of decryption.