人與人之間的交流可能會藉由聲音、身體和表情來互相溝通，且溝通是非常複雜並包含有多模態(multimodal)的資訊夾雜在其中，例如：語句、語調、眼睛注視方向、手勢或肢體動作等，同時資訊又會互相影響、交互作用，相同的語句、不同的語調、不同的肢體動作，表達的意義也不同。當人們表達情緒的時候，除了全域的情感外，細部其實是一個連續性的情緒變化，每個時間點都是有不同的情緒，帶有非常豐富的資訊，而這兩種不同的情緒，全域情感及連續情緒都是非常重要的。因此本論文應用人類訊號處理，擷取身體語言與語音兩個行為特徵模態，並系統性地利用不同時間區間對於行為訊號特徵進行編碼，針對情緒三個維度激動程度、正負向與自主程度利用兩種機器學習演算法進行連續情緒辨識，分別是支持向量迴歸與Sequence to Sequence Learning，實驗結果顯示，藉由增加豐富特徵的時間資訊可以有效地幫助連續情緒辨識，結果得到了顯著性地提升，接著利用連續情緒應用於全域情感辨識，結果顯示，雖經過中間連續情緒編碼，但還是有效地幫助全域情感辨識，最後，我們更利用人類心理學Thin-slicing情感接收機制，進一步的提高全域情感辨識相關性，同時也發現一個非常有趣的事情，兩個不同的機器學習演算法連續情緒辨識結果差不多，但於全域情感確呈現截然不同的樣貌。

Human communication and interaction is a multimodal structure through voice, facial expression, body action, which are able to convey the people’s affect. In different moment of interaction, people feel different emotion. The expressions of emotion c be annotated by global emotion and continuous emotion. Continuous emotion is very complex and informative, but continuous and global emotion are both important. Therefore, we perform time encoding framework at behavior signal, body language and audio, to track continuous emotion, and focus on three dimensions of emotion which are activation, valence and dominance. During the training and testing process, we used two machine learning algorithms, support vector regression and sequence to sequence learning. Moreover, we extend our framework by two direction. First, we concentrate on continuous emotion tracking. Secondly, we use continuous emotion to predict the global affect. Comparing the previous study, continuous emotion tracking results achieve better performance of our system, and it also effectively help the global affect recognition. Interestingly, the continuous emotion tracking results bring the human perception mechanism of thin-slicing and further improve the global affect correlation.

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