J.C. Stoffel et al.: “A Survey of Electronic Techniques for Pictorial Image Reproduction” IEEE Transactions on Communications, vol. Com-29, No. 12, Dec. 1981, pages. |
1898-1925, XP000560531 New York (US) *p. 1904, right-hand column, paragraph 3-page 1908, left-hand column, Last line*. |
1977 SID International Symposium, Digest of Technical Papers; Society for information Display, Los Angeles (US, 1977 pp. 124-125). |
K.W. Wong et al., Adaptive switching of Dispersed and Clustered Halftone Patterns for Bi-Level Rendition: XP000605139. |
J.C. Stoffel et al.: “A Survey of Electronic Techniques for Pictorial Image Reproduction”, IEEE Transactions on Communications, vol. COM-29, No. 12, Dec. 1981, pp. 1898-1925, XP000560531. |
K.Y. Wong et al.: “Adaptive Switching of Dispersed and Clustered Halftone Patterns for Bi-Level Image Rendition”, 1977 SID International Symposium, Digest of Technical Papers; Society for Information Display, Los Angeles (US), 1977, pp. 124-125, XP000605139. |