可調性視訊編碼(Scalable Video Coding；SVC)允許視訊資料依其重要性進行分層，故可適用於各種不同功能的終端裝置，以及具備不同傳輸特性的網路傳輸媒介。為了使SVC壓縮後的資料易於在抹除通道(erasure channel)上被傳輸，SVC視訊資料可被各種不同的前向錯誤更正碼編碼，例如：猛禽碼(Raptor code)。在本篇論文中，我們提出了一種適用於SVC串流傳送的輕量跨階層保護技術；在接收端，該技術可以讓較高層(例如：SVC加強層)的編碼符號有助於較低層(例如：SVC基本層)資料的重建。簡要地說，我們所提出的技術具有以下的優點：一、每一層資料的編碼率(code rate)仍可維持和原先沒有跨階層保護時的編碼率一樣。二、編解碼的計算複雜度比德國的佛朗霍夫海因里希研究所(Fraunhofer Heinrich Hertz Institute；Fraunhofer HHI)所提出的對等技術-階層感知FEC(Layer-aware FEC；L-FEC)技術來的低。三、實作方法與傳統的單階層FEC編解碼器之實作方式相容。四、在我們所提出的機制中，不同階層可以同時使用不同的FEC編碼來進行實作。根據在DVB-H廣播網路上的模擬結果，相較於沒有跨階層保護的技術方法，針對SVC基本層資料，我們所提出的跨階層保護機制，在接收端可以提升1%到45%的成功資料重建機率。

Scalable Video Coding (SVC) enables the partition of video data into layers of different priorities foradapting to both the diversities of terminal capabilities and the variation of network transmission mediums. Tofacilitate SVC data transmission in an erasure channel, the video data may be encoded by Forward ErrorCorrection (FEC) codes, such as Raptor codes. In this paper, we propose a lightweight inter-layer protectionscheme for SVC transmission, which enables the encoding symbols in a higher layer, e.g., in an SVCenhancement layer, to enhance the data reconstruction in a lower layer, e.g., in an SVC base layer, in thereceiver side. In brief, the proposed scheme has the following advantages: First, the FEC code rate in eachlayer can be kept the same as the one without inter-layer protection. Second, the computation overheads ofencoding and decoding are reduced in comparison to a similar scheme called Layer-aware FEC (L-FEC)proposed by the Fraunhofer Heinrich Hertz Institute (Fraunhofer HHI). Third, the implementation of theproposed scheme can be compatible to the implementations of conventional single-layer FEC codes. Fourth,in the proposed scheme, different FEC codes can be applied to different layers of SVC video data. Incomparison to the scheme without interlayer protection, the simulation result shows that in a DVB-H broadcastchannel, the scheme exhibits 1% to 45% enhancement on the probabilities of successful reconstruction of theSVC video data in the base layer.