A Study on Data Hiding in 2D Barcodes by Module Adjustments and Color Gradations

• Main Authors: Yuan-Ming Wu, 吳原銘
• Other Authors: Da-Chun Wu
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/85934525548855066358

碩士 === 國立高雄第一科技大學 === 電腦與通訊工程所 === 97 === The data hiding techniques have developed recently due to the technology improvements in today’s society. Those techniques are used on many different fields, such as internet, music, video and etc. 2D Bar Codes are used widely on recording all kinds of data types. It has the unique function which can record variety of information such as word, sale products and identification numbers and etc. After combining the cell phone with the 2D Bar Code’s decoding function, 2D Bar Code has more flexibility than before, which is very convenient for daily life. This thesis proposal contains two methods for data hiding in 2D Bar Code which base on rectangular modules as unit. First, in a pair of modules with different color, the way is to adjust slightly module matrix by using horizontal length and vertical width for embedding data. The purpose of this approach is a technique for module to adjust module matrix width and height one by one continuously. The technique can eliminate spaces without uneven shapes between each module, which improves invisibility of data hiding. Second, to change corner pixels of a module for embedding data by using Bilinear Interpolation to recalculate other pixels which makes the module represents gradient look and smooth without breaks. This approach mentions mainly no-edged effects will be produced in the boundary between gradient module and surrounding module in the same color. The no-edge technique makes module more smooth and even in the boundary. From the experimental results, both of the adjustable module and gradient module approaches are practicable for data hiding in 2D Bar Code.