網際網路協定電視(IPTV)是結合網路與多媒體的應用服務，其主要特質為利用網路傳送影像、聲音、資料等資訊的一種三合一整合服務(Triple Play)，其可細分為遞送群播電視、隨選視訊、音樂、網路電視、網頁服務、以及電子郵件收發等。上述之服務項目是一般傳統電視所無法提供之互動式服務。
使用者經驗(Quality of user Experience, QoE)則是IPTV服務成功的重要因素之一，使用者QoE越高代表使用者對IPTV服務越滿意，提升使用者的QoE以擴增使用IPTV服務的客戶是IPTV服務業者的目標。
IPTV服務中頻道切換時間(Channel zapping time)是影響使用者的QoE的原因之一，定義為：使用者切換頻道時按下遙控器按鍵，到畫面顯示到螢幕上這段時間。這段期間會有黑屏現象並影響到使用者的感受，黑屏的時間太長會讓使用者的QoE下降，因此頻道切換時間被視作是衡量使用者QoE的一項重要指標。
現有的文獻有數種減少頻道切換時間的方法，其中一種是預測使用者行為以預收頻道，當使用者的操作行為滿足其預測時，使用者可以馬上切換至預收頻道，減少頻道切換時間，達到使用者的QoE的提升。我們參考這些方法優點提出新的頻道預收策略，其策略為結合資料比對(Pattern Matching)、模式分析(Pattern Analysis)與資訊理論(Information theory)概念之演算機制預測使用者下一步的轉台操作並預收相對應的頻道。將預測的頻道預收至機上盒，提升預收頻道的準確率，讓使用者更容易切換到預收頻道以減少頻道切換時間。

Internet Protocol Television (IPTV) is a combination of network and multimedia applications. It is a triple play service such as multicast television, Video on Demand, music, Internet television, Web services and network mail services that transmits video, audio and data. The above services are not provided by traditional television.
Quality of user Experience (QoE) is one of the key factors involved in the success of IPTV service. The higher the QoE, the more satisfied users of IPTV services are. Enhancing the QoE in order to increase the number of customers in IPTV service is the primary goal of IPTV service providers.
Channel zapping time is one of the factors that affects QoE in IPTV Service, and it is defined as: Delay time is the period from a channel request being sent by remote control until the first video frame appears on the screen. The screen is black during the delay time and affects user experience, and user experience is worse as a result of a longer channel zapping delay time. Therefore, channel zapping time is seen as an important measure and indicator of QoE.
Literature on this topic has described are several methods by which to reduce channel zapping time. One of those methods is predicting user behavior and then prejoining a related channel. When the user's operational behavior matches the predicted user behavior, users can immediately change to the prejoin channel and reduce channel zapping time, thus enhancing QoE. We refer to the advantages of these methods and propose a new prejoin channel strategy, which is a mechanism combining pattern matching, pattern analysis and information theory concepts to predict a user’s next channel change operation and then prejoining a corresponding channel. Receiving a prejoin channel in the set-top box makes it easier for users to change to the prejoin channel by enhancing the accuracy of the prejoin channel and thus reduces the channel zapping time.

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