Interactive Object Segmentation and Recognition

HASH(0x1d244e30)

謝郁志(Yu-Chih Hsieh)

指導教授 ： 陳煥宗

國立清華大學/電機資訊學院/資訊工程學系/碩士(2008年)

摘要

利用電腦切割及辨識影像中的物件，一直是電腦視覺領域中，兩個困難且具有挑戰性的問題。針對這兩大問題，已經有很多人提出各式各樣的方法來試圖解決。然而，多數的方法，都只是將這兩類問題各自獨立出來解決。在這篇論文中，我們實作一個互動式物件切割與辨識的系統，同時解決上述兩個問題！

這篇論文最主要的概念，是從拼圖而來的。首先，我們將樣本影像，利用有效率的演算法，切成很多不規則的碎片。將這些碎片，利用一些共通元素的分佈來表示。利用這些碎片的共通元素分佈，當成碎片的特徵，來學習分類器。在分類的時候，將測試的影像同樣切成很多的碎片，對每一塊碎片利用我們的分類器來分類取得物件類別；分類完成之後，物件切割也自然完成了。在分類結束之後，有些碎片仍然會被分成錯誤的類別。將這些碎片，利用正確分類的碎片所提供類別和影像中的相對位置的資訊，來修正成正確的類別。

我們的系統，對於像是草地、樹葉、天空等紋理的影像或物件，有不錯的效果。對於主題明顯的影像，效果也表現得不錯。在最後的修正過程，也確實能正確地運作表現。

關鍵字

物件切割 ； 物件辨識 ； HASH(0x1d24a730)

並列摘要

Abstract

Object recognition and segmentation are two of the most difficult and challenging problems in computer vision. Many approaches have been proposed to solve these problems. However, these two problems are usually addressed independently in previous approaches. We implement an interactive object segmentation and recognition system to solve these two problems at the same time.

The main idea of this thesis comes from jigsaws. First, we over-segment every input image into many superpixels. Then we classify all superpixels based on the bag-of-words model. Finally, we combine the superpixels that belong to the same labels to obtain segmented objects. After the classification stage, there are still some misclassified superpixels. Based on the information derived from user scribbles, we can refine the misclassified superpixels interactively. The information we used in the refinement process is the spatial and co-occurrence relations between objects of different categories.

Our object segmentation system favors texture objects, such as grass, tree, sky, and so on. Images with a significant subject can also have good labeling accuracy. The experimental results show that the refinement process indeed helps to improve the preliminary segmentation results.

並列關鍵字

segmentation ； recognition ； texton

參考文獻

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