分散式影像編碼在手機上的實現與有效率的回饋通道

Distributed Video System Realized on Mobile Device with Efficient Feedback Channel

陳群元(Chun-Yuan Chen)

指導教授 ： 吳家麟

國立臺灣大學/電機資訊學院/資訊工程學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.10920

摘要

分散式編碼是一種新的編碼方式，不同於以往的編碼架構，分散式編碼有著較簡單的編碼器及較複雜的解碼器，所以分散式編碼很適合在運算能力較差的機器上做分散式編碼。由於分散式編碼的特性，分散式編碼在有者多台執行影像編碼的感應器應用上面變得越來越熱門。例如視訊會議、手機錄影，都可以利用分散式編碼的好處，降低手機裝置上的耗電量，而另一方面我們可以利用運算能力極強的伺服器，例如擁有雲端計算能力的伺服器，來做較難的解碼。
但是我們發現一個嚴重的問題，雖然在高效能的計算機上編碼和解碼都可以在很快執行。但是由於現行的分散式系統使用的是低密度奇偶校驗碼，所以在解碼的過程中，解碼器和編碼器需要大量的溝通。這在現實的運用上是一個相當大的問題。所以在我的碩論裡，不但會在手機裝置實現分散式系統，並對來回溝通上做更有效率的處理。

關鍵字

分散式視訊編碼 ； 低密度奇偶校驗碼

並列摘要

DVC is a new paradigm video codec. Compare to traditional video codecs, DVC has light-weight encoder and heavy weight decoder, so DVC encoder is suitable for applications in which the encoding is done on low computing power devices. Because of this characteristic of DVC, DVC is more and more popular in the cureless sensor networking era. On one hand, DVC saves electricity in mobile video conference and video recording because of its lightweight encoder. On the other hand, the DVC decoder can run on power server, such as cloud-hashed data center
Unfortunately, even though DVC encoder and decoder run rather fast with the aid of powerful hardware, there are a lot of communications between encoder and decoder because of the LDPCA is adopted. It is a big challenge. In our work, we realized a practical DVC system on mobile device and proposed an efficient feedback channel to face the challenge.

並列關鍵字

Distributed Video codec ； LDPCA

參考文獻

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