Single-Shot Person Re-identification Based on Improved Random-Walk Pedestrian Segmentation

基於改進隨機漫步影像分割之單張影像行人辨識

張幼臻(Yu-Chen Chang)

指導教授 ： 賴尚宏

國立清華大學/電機資訊學院/資訊工程學系/碩士(2011年)

https://doi.org/10.6843/NTHU.2011.00512

摘要

Single-shot person re-identification is to match pedestrian images from different cameras under the condition of large illumination variations, different viewpoints, cluttered background, and inadequate information of single-shot case. To deal with these challenges, we propose a single-shot person re-identification method with improved pedestrian segmentation by incorporating shape prior and color seed constraints into Random Walk in this thesis. Our method is a four-step procedure which includes finding feature correspondences and person recognition. Based on an improved Random Walks algorithm, we segment accurate foreground masks from a detected pedestrian region by combining the shape prior information and the color histogram constraint into the Random Walk formulation. . Then color features of HSV histogram and 1-D RGB signal aided by texture feature from each part are used for the person recognition. In addition, we choose the correct match by matching the similarity scores of all features with appropriate weight selection. The experimental results demonstrate improved segmentation results on some real images by using the modified Random walk segmentation. In addition, we also show superior performance on person re-identification accuracy by using the proposed algorithm compared to the previous representative methods.

關鍵字

行人辨識 ； 隨機漫步影像分割 ； 用於單張影像實例

並列摘要

單張影像行人辨識是想在亮度差異大、不同視角且背景複雜的狀況加上單張影像不足夠的資訊困難中去找尋出現於不同位置上的行人。在本文中我們加入人行機率分佈及初始點上的顏色資訊來改善隨機漫步行人影像分割，並提出基於改善後的行人影像分割實做單張影像行人辨識去處理前面提及的困難。我們所提出的方法是個四步驟的流程，其中又可分成兩大部分:定義相對區域及行人辨識。根據改善後的隨機漫步影像分割，我們可以在行人偵測區域中取得更精確的前景。接著是從相對應的區塊中獲得色相飽和度明度分佈及一維三原色光訊號的顏色特徵，同時加上紋理分析的幫助做行人辨識。除此之外，我們利用自己定義的權重篩選來合併三種特徵決定出影像比對的相似值再去找尋正確的行人配對。透過實驗結果顯示改善後的隨機漫步影像分割提升了真實影像上前景區塊的結果。同時利用我們的行人辨識方法所得到的準確率也比過去代表性的方法有卓越的表現。

並列關鍵字

Person Re-identification ； Random-Walk Pedestrian Segmentation ； Single-Shot Case

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