The Coding And Displaying Technology Of Digital Ink

Nowadays, with many input methods, it is more and more convenient and easy to use keyboard to input information. But using keyboard exists some disadvantages: 1. The content we can input is limited. For example, some uncommon words cannot be input. If we want to input new style fonts and words, a new font library should be installed. And random character cannot be input. 2. Some people forget how to write words in a correct way because they use keyboard too much. Especially for young generation, they rely on the keyboard, as a result, they can not write Chinese or English words correctly, let alone to write in a beautiful way. 3. The font input by the keyboard is singleness. Especially in the mobile phone application, because of limited storage space, only one font style can be displayed which will be seen very monotonously. For the person who is very good in calligraphy, the writing can be seen for the opposite side is on high demand. 4. The content input by keyboard can be easily forged. But the specific personal written style is constant so it is very hard to be imitated.In this paper, we use the digital ink technology to deal with the shortcoming of tradition keyboard input. Digital ink is a human-centric technology for a rich and natural human-computer interaction. It combines the expressive power of human handwriting with the power of a tablet PC. Digital ink is a breakthrough technology because it has many excellent characteristics. For example, it can be easily zoomed in and zoomed out. What's more, the digitized handwriting can be converted to standard text through handwriting recognition, or it can remain as handwritten text.To make digital ink a first-class user experience, our researches are mainly focusing on using Bezier curve to encoding digital ink to reduce storage space and carrying out anti-aliasing techniques to improve its displaying quality. With these technologies, it can be transmitted over wireless network with limit bandwidth and it can be displayed smoothly and clearly.Some key issues of digital ink processing are: (1). how to encode the digital ink efficiently so that very small memory is required to store the inks; (2). how to process the digital ink so that it can display smoothly and beautifully when it is very small or large. The most challenging thing is when it is very small, it will be very hard to be seen clearly. So we should find some good methods to tackle this problem.Based on this background, we design the on-line and off-line digital ink encoding and decoding system. The characteristic and the creation in this thesis is depicted below:1. Because skew-like edge exits when drawing the lines and curves on the screen directly, a kind of anti-aliased technology named Wu method is applied to draw lines with constant width or variable width, square, circle, ellipse, Bezier curve in order to improve the display quality dramatically and display smoothly and beautifully.2. Because storage space of bitmap and JPEG format is a bit large, Bezier curve is applied to reduce the storage space. For the online digital ink, we realize the corner point detection, using least square method to fit Bezier curve to the origin written track, applying the anti-aliased technology to encode the digital ink, which can reduce the storage space and improve display quality. For the offline digital ink, we realize the contour method and skeleton method to encode the ink. For the contour method, we carry out binarization, contour extraction and tracing, corner point detection, Bezier curve method and seed filling to encode the ink. For the skeleton method, we carry out binarization, skeleton extraction and tracing, width recording, Bezier curve to encode the ink.3. We carry out the experiments such as zooming in and zooming out by the image interpolation method and Bezier curve method. And we compare the effect of these two methods.4. Boland C++ Builder platform is used to realize the algorithms and construct the encoding and decoding system. J2ME technology to utilized to realize it on the mobile phone.