Mapping Two-Dimensional Plots to a Spherical Surface using Elliptical Grid Mapping

Naoki Kita1,2
Grégoire Cliquet3
Kazunori Miyata1

CVM 2020

teaser image


Visual cryptography (VC) is an encryption technique for hiding a secret image in distributed and shared images (referred to as shares). VC schemes are employed to encrypt multiple images as meaningless, noisy patterns or meaningful images. However, decrypting multiple secret images using a unique share is difficult with traditional VC. We propose an approach to hide multiple images in meaningful shares. We can decrypt multiple images simultaneously using a common share, which we refer to as a magic sheet. The magic sheet decrypts multiple secret images depending on a given share. The shares are printed on transparencies, and decryption is performed by physically superimposing the transparencies. We evaluate the proposed method using binary, grayscale, and color images.


Spherical mapping results
MNIST visualization



This work was supported by JSPS KAKENHI Grant number 19K24338.


  title = "Mapping two-dimensional plots to a spherical surface using elliptical grid mapping",
  journal = "Graphical Models",
  volume = "109",
  pages = "101067",
  year = "2020",
  issn = "1524-0703",
  doi = "",
  url = "",
  author = "Naoki Kita and Grégoire Cliquet and Kazunori Miyata",
  keywords = "Mapping technique, Layout optimization, Data visualization, Virtual reality",