以內容為基礎的高動態範圍影像色調映射

Content-Based Tone Mapping for High Dynamic Range Image

吳保樹(Bao-Shu Wu)

指導教授 ： 郭忠民

義守大學/電機資訊學院/資訊工程學系/碩士(2014年)

https://doi.org/10.6343/ISU.2014.00140

摘要

由於高動態範圍影像的出現，現在可以得到較以往傳統的數位影像具有更高動態範圍的影像，所以可以把真實場景中的亮度完整的重現。但是現有的顯示器大多都是低動態範圍的顯示器，如果拿來顯示高動態範圍影像的話會令高動態影像失去其高動態的效果。
為了解決此問題，就有了色調映射的技術出現。色調映射演算法是用來將高動態範圍影像對應至低動態範圍中，來使低動態範圍的顯示器可以正常顯示高動態範圍影像。在本文中，我們提出了一個以高動態影像內容為基礎去進行色調映射的方法，一開始先將影像作直方圖分析，得出此影像的亮暗分佈之後，以此分佈結果去對影像進行判斷，分別對判斷出的不同影像採取不同的色調映射方式，最後將結果進行權重加成後，影像結合起來成輸出影像。

關鍵字

高動態範圍影像 ； 色調映射

並列摘要

Since high dynamic range images are available, we can obtain images with larger dynamic range than that of the traditional digital images, and therefore we can reproduce the luminance of real world. However, most of the existing monitors support low dynamic range. It will lose the visual effect when using the traditional monitors to display high dynamic range images.

In order to solve this problem, researchers proposed tone mapping techniques. Tone mapping algorithms maps high dynamic range images to low dynamic range images effectively, and allows the monitors displaying the images with high dynamic range correctly. In this thesis, we propose a content-based tone mapping algorithm for displaying high dynamic range images. First, we analyze image histogram to obtain the image distribution for light and darkness. Based on the analysis, we can determine the proper weighting for tone mapping to reconstruct the output image.

並列關鍵字

High Dynamic Range Imaging ； Tone mapping

參考文獻

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