教師著作

Now showing 1 - 4 of 4

Elimination of artifacts in encrypted binary images by modified digital halftoning technique.
(International Society for Optical Engineering, 2004-01-18) Hsi-Chun Wang; Juo-Han Sung; Yung-Hui Chen
An anti-counterfeiting feature, latent image, has been widely applied for banknotes and security documents. The hidden pattern of denomination by intaglio printing process can be observed by viewing the bill at certain angles of elevation. While designing the latent image, a continuous-tone cover image and a binary figurative pattern are used. The continuous tone image is halftoned by horizontal and vertical line screen, respectively. The binary figurative pattern then serves as a mask to render the corresponding area of horizontal and vertical line screen on the figurative region and background region, respectively. These procedures can be done by many available commercial softwares. However, there are various artifacts such as gaps in the junctions of horizontal and vertical screen lines, discontinuous screen lines and the white or black artifacts on the edges of the latent image. The retouching of the resulting latent image needs to be carefully and skillfully handled. In this research, we developed an automatic process to generate the artifact-free latent image inside a cover image by modified digital halftoning techniques. The methods we applied include: (1) To design new 8x8 threshold matrices in order to make a perfect joint of the horizontal and vertical screen lines. (2) To use the linear scaling adjustment to enhance the cover image not resulting discontinuous line. (3) To register the 8x8-based figurative pattern to the 8x8 threshold matrix and to avoid the visual artifacts. For latent image detection, a frequency domain treatment by FFT (Fast Fourier Transformation) and inverse-FFT is used to extract the encrypted image. This is especially useful for machine-readable applications. The results show that the developed process in this research does have the ability to automatically generate the desired latent image without any artifact. It also saves the costly retouching in the existing process. A frequency domain detection method is applied to extract latent images. The proposed techniques in this research also have great potential to proceed security printing in a digital way.
印刷文物典藏內容展示研究--展示主軸的發展
(2008-07-31) 吳祖銘; 徐照夫
文物典藏端賴史料研究的方向指引，史料研究必須有文物為佐證，兩相依存均具同等的重要性，本研究旨在透過科技文脈與展示觀點的探討，以建構「印刷文物典藏地圖」。本計畫係為開展第二階段的工作，為前期研究的延續，是以展示規畫的需求，結合既有館藏，發展展示議題與軸心，以推動印刷文物典藏展示的實踐。
台灣石版印刷術的傳入與發展之研究
(2000-10-31) 吳祖銘
自本世紀以來，藉由科技昌明與知識普及的趨勢，就科技發展的歷程來看，昨日智慧的累積，延伸出今日生活的實踐，研究人類科技史，宛若藉鏡過往，回顧與反思自身的發展，在人類文明價值的重大意義。石版印刷已消失至少五十年的時間，目前各種相關工廠、工具、技術都已難以找到，有些早期印刷品、書籍、商標可以在二手市場找到，或是專業圖書館的善本書，盛行的原因一則可能是它的特性，快速而簡便，所以印製出來的成品，偏向以大眾需求為主導，出版品並不是非常精審，價格也相對的便宜許多，因此它如何發生，背景及影響如何，為何結束正是研究要旨所在。 1981年，研究者因協助師大陳景容教授為版畫製作尋訪石版版材，得緣結識位於台北市康定路早期石版印刷業者──昭明社，雖然其後於火災災變後結束營業，但將以此線索尋訪該經營事主；1982年，研究者因協助版畫家劉自明先生，購得台北市西藏路信華印刷王大明老師傅所藏之落石機，並以鋅版仿石版原理完成首宗平版畫創作。根據以上所述，本研究目的有：１．考證石版印刷術傳入台灣的緣由與歷史背景。２．發掘與整理台灣石版印刷使用之相關機材、文物與出版品。３．了解石版印刷術在台灣的發展史實、技術的擴散與歷史定位。本研究性質屬於「質」的研究分析工作，係以台灣石版印刷術興衰發展史考為主要探討課題，配合具有歷史的石印業者之佐證，擬透過歷史文獻的分析、田野調查的觀察與紀錄、口述歷史的耆老與專業前輩的錄音訪談，並透過專家諮詢方式，提供訪談前問題的指導，資料整理後進一步客觀的研討，並透過影片、影帶及幻燈片拍攝原始資料，包括靜態文物與動態實景的紀錄，俾供驗證與提供後續研究之需要。研究預定成果分別為： 1. 具體指出石版印刷術在台灣的發展階段，比較其歷史價值。 2. 明確列述本發展階段的史實脈絡與重要文物，建立台灣石版印刷文物圖錄，以供博物館收藏單位典藏之指引。 3. 拍攝紀錄本階段石版印刷相關幻燈圖片、動態影片資料，以供驗證與後續發展科技影片，輔佐靜態文物展示的需要，提供科技影片素材蒐集的參考。
台灣印刷科技史綱建構之研究
(2000-07-31) 吳祖銘

教師著作

Browse

Filters

Settings

Sort By

Results per page

Search Results