影像串流於無線網路上進行傳輸時往往會面臨到或多或少的挑戰，其中因為受到無線訊號的錯誤干擾，會使得接收端在收到資料影像串流時，造成影像串流品質的下降。前向糾錯機制〈Forward Error Correction〉是一種經常在無線網路上被拿來使用於傳輸影像串流時的錯誤回復機制。傳統封包回復制的前向糾錯機制使用一個完整大小的冗餘資料封包，去回復可能只有幾個位元或幾個位元組錯誤的資料封包。此種作法在資源相對於有線網路來的較少的無線網路上來進行是比較沒有效率的。也因此，在這篇論文中，我們提出了依虛擬切割之互斥或錯誤糾正機制 (XOR-EC)。藉由此機制，假定可以獲知突發式位元錯誤長度的資料，我們可以在突發式位元通道上以有效的方式降低回復負擔的資料量。XOR-EC機制使用虛擬切割封包的方法來避免因實際切割調整封包而增加的額外的封包標頭資料量，並能藉此虛擬切割的方式，產生較低資料量的回復負擔。在和相關研究的幾個比較項目的結果上，我們的實驗結果在回復負擔的數值上呈現了相對較低的表現，同時在有效的封包遺失率上也維持了好的回復能力。

Video transmission over wireless networks faces challenges due to suffering from wireless errors, which causes lower video quality. The well-known error recovery scheme “Forward Error Correction (FEC)” is generally used to protect the video quality. Packet-level FEC uses a complete packet to recover the wireless errors, which are just a-few-bit-or-byte errors inside the packet. Such approach is not only inefficient but also causes great recovery overhead problems. Hence, in this thesis, a virtual fragmentation-based XOR error correction (XOR-EC) scheme is proposed which effectively reduces the FEC recovery overhead over bursty channels as long as the burst bit error length can be known. The XOR-EC scheme uses the virtual adaptation to generate the reduced FEC redundancy without increasing the packet header overhead. We evaluate the performance metrics with other proposals, and our experimental results outperform in recovery overhead with lower values of recovery overhead than other proposals, and still maintain good recovery ability in effective packet loss rate.

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