對於影像串流高品質的影像對於即時性的影像處理是非常重要的一個環節。傳輸的過程中，種種因素會導致影像內容丟失，例如傳輸型態改變、傳輸中遺失資料，特別是在資料切換時。資料切換一般發生在影像訊號的切換，這可能導致影像的數據在記憶體或緩衝器中不連續性進而導致影像偏移。針對這樣的議題，目前參考文獻的解決方式採用前後張影像幀差異去檢測異常的影像現象，但目前這樣的演算法可能消耗很多硬體資源和記憶體空間。本論文提出一種運用影像傳輸協定的特性，利用解碼影像封包所得到像素點，並採用像素點預測方式，並將檢測方式應用於影像系統上。所提出方法及影像系統架構實現於SoC-FPGA晶片平台，此開發平台包括DDR3 ram，閃存和交換接口。實驗結果表明，所提出的方法在正確率高達99%，並節省更多邏輯元件的使用與減少影像資料於記憶體的占用。

Image/video processing in real-time is always in high demand for the quality of video. There are several factors which cause the loss of the video content, such as the type of transmission, missing data and especially data switch. Data switch generally occurs in the alternation of the video signal, which can cause the discontinuity of data during the video data stored in buffer or memory. The current method which adopts frame difference for detecting this issue may consume many resources and memory footprint. This paper presents a method which uses the video pixel prediction to detect the freezing event. The method is implemented with a video system which employs the System-on-chip (SoC) architecture with Field Programmable Gate Array (FPGA) and other components including DDR3 ram, flash, and exchange interfaces as the main processing platform that prevents this problem through freezing detection. The result of evaluation shows that the accuracy of the proposed method is above 99%, in terms of saving more logic usage and reducing the footprint of the memory on the video system.

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