近年來由於不同尺寸顯示設備之興起，如電視、智慧型手機、平板電腦、電腦螢幕及立體顯示器等，帶動（立體）圖像與（立體）影片縮放技術的發展。大多數非線性調整解析度方法會偵測圖像中重要區域，維持重要區域的形狀，但同時造成圖像中不重要的區域產生較大的變形，在這些非線性變形研究中，忽略物體變形一致性，有時會造成物體或結構線明顯扭曲、立體視差失真及時間相干性不一致。因此本論文提出一個三維物體導向之變形和裁剪方法來解決物體不一致形變的問題和保持物體的形狀、立體視差及時間相干性。在最佳化方法設計上，影像中物體都經由相似轉換來保持一致性與時間相干性，顯著內容物維持原本的比例，而低重要物體被扭曲盡可能接近線性轉換；此外，靈活邊界約束融入最佳化解法中，讓顯著物體落在重定視頻內，裁剪掉重定視頻以外的區域。本研究方法可適用於單一圖像、影片及立體影像之縮放。由定性與量化分析結果顯示，驗證此方法之實驗結果均優於近年先進方法所產生的結果。

此外，亦把此技術應用到地圖中。旅遊地圖和指引地圖都是屬於特殊目的之地圖，這些地圖一般都是為了特定的主題而設計，而這些含有特殊目的地圖的道路網路拓撲結構通常會比道路的幾何精度更來的重要，因此本論文中道路網路變形方法的目標是為了更容易產生各種特殊目的地圖和改變地圖中所代表的主題。這個想法基於使用者的心理地圖來變形道路網路，同時使用最佳化程序來執行道路網絡的扭曲變形。提出的方法中包括新穎的算法用於估計道路顯著性、各種幾何約束、美學約束及用戶指定約束來完成道路網絡變形。這些地圖能夠用於旅遊地圖和指引地圖，所以不僅能夠提供直觀路線規劃和導航任務，也能夠把主題性地圖視覺化呈現。在實驗結果中所生成的旅遊地圖和指引地圖，顯示出此系統能夠有效產生各種專用地圖。

QR碼通常用於嵌入訊息，人們可以方便地使用解碼設備來解讀QR碼而獲取訊息。近年來隨著QR碼的快速崛起，越來越多形式在生活上出現，除了一般常見的黑白兩色之外，藝術家和設計師把它變換成其他顏色或花樣，例如文字、商標或圖像轉換成美觀的QR碼，層出不窮的創意皆可在QR碼上展現出來。在最近幾年，有研究者賦予美學元素來自動產生美觀的QR碼，然而他們的方法所生成的QR碼仍然不夠美觀，因此本論文提出了兩階段方法生成高品質美觀的QR碼。在第一階段中，利用高斯-約旦法改變原始QR碼產生出概略性QR碼；在第二階段中，用最佳化渲染機制來把圖像與概略性QR碼合成高品質美觀的QR碼，同時維持QR碼的可讀性以及保持原本彩色影像的特徵。從實驗結果中，本方法提高了QR碼的外觀且最佳化過程是即時的。

In recent years, the (stereoscopic) image/video retargeting fast rises to become an important technology due to many display devices with different resolutions, such as TVs, smart phones, tablet PCs, 3D displays, and so on. Most non-linear warping methods used in image/video resizing are to preserve the aspect ratios of prominent regions and distort unimportant contents. However, these methods sometimes cause significant distortion of objects or structure lines, depth distortion, and unnatural temporal motions, because of ignoring the consistency in object deformation. Therefore, a floating boundary with volumetric warping and object-aware cropping is proposed to address those problems. In the proposed scheme, visually salient objects in the space-time domain are deformed as rigidly and as consistently as possible by using information from matched objects and content-aware boundary constraints. The content-aware boundary constraints can retain visually salient contents in a fixed region with a desired resolution and aspect ratio, called critical region, during warping. Volumetric cropping with the fixed critical region is then performed to adjust stereoscopic videos to the desired aspect ratios. The strategies of warping and cropping using floating boundaries and spatiotemporal constraints enable our method to consistently preserve the temporal motions and spatial shapes of visually salient volumetric objects in the left and right videos as much as possible, thus leading to good content-aware retargeting. In addition, by considering shape, motion, and disparity preservation, the proposed scheme can be applied to various media, including images, stereoscopic images, videos, and stereoscopic videos. Qualitative and quantitative analyses on stereoscopic videos with diverse camera and considerable motions demonstrate a clear superiority of the proposed method over related methods in terms of retargeting quality.

In addition to the resizing method, we extend our warping technique to maps. Tourist and destination maps are thematic maps designed to represent specific themes in maps. The road network topologies in these maps are generally more important than the geometric accuracy of roads. A road network warping method is proposed to facilitate map generation and improve theme representation in maps. The basic idea is deforming a road network to meet a user-specified mental map while an optimization process is performed to propagate distortions originating from road network warping. To generate a map, the proposed method includes algorithms for estimating road significance and for deforming a road network according to various geometric and aesthetic constraints. The proposed method can produce an iconic mark of a theme from a road network and meet a user-specified mental map. Therefore, the resulting map can serve as a tourist or destination map that not only provides visual aids for route planning and navigation tasks, but also visually emphasizes the presentation of a theme in a map for the purpose of advertising. In the experiments, the demonstrations of map generations show that our method enables map generation systems to generate deformed tourist and destination maps efficiently.

QR code is generally used for embedding messages such that people can conveniently use mobile devices to capture the QR code and acquire information through a QR code reader. In the past, the design of QR code generators only aimed to achieve high decodability and the produced QR codes usually look like random black-and-white patterns without visual semantics. In recent years, researchers have been tried to endow the QR code with aesthetic elements and QR code beautification has been formulated as an optimization problem that minimizes the visual perception distortion subject to acceptable decoding rate. However, the visual quality of the QR code generated by existing methods still leaves much to be desired. In this work, we propose a two-stage approach to generate QR code with high quality visual content. In the first stage, a baseline QR code with reliable decodability but poor visual quality is first synthesized based on the Gauss-Jordan elimination procedure. In the second stage, a rendering mechanism is designed to improve the visual quality while avoid affecting the decodability of the QR code. The experimental results show that the proposed method substantially enhances the appearance of the QR code and the processing complexity is near real-time.

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