隨著多視角3D視訊的出現且趨於成熟，網路營運商正面臨著如何解決網路流量因而增長的挑戰，我們觀察到利用Depth image based rendering (DIBR)這個技術在網路中進行群播會是一個有效的方式，因為許多的視角可以透過這個技術被合成出來，因而不需要在網路中進行傳遞，儘管如此，在行動設備上進行合成對於行動設備是一個龐大的負擔，近年來，行動邊緣運算(Mobile Edge Computing,MEC)的出現使得網路邊緣也可以進行DIBR的合成，因此，在這篇文章中，我們針對了這種架構制定了一個新的問題，稱為Multi-view Multicast Synthesisand Delivery (MMSD)，並且設計了一個有效的演算法，稱作Merge Search ForestAlgorithm (MSFA)，且證明當合成距離的限制為2時，MSFA是一個O(1)近似的演算法，模擬的結果顯示MSFA在總傳輸和計算的成本優於已存在的方法30%到50%。

With the quick emergence of multi-view 3D videos, network operators now face a new challenge to resolving the dramatic increase of the network bandwidth required to support all desired views in a video. We have observed that Depth-Image-Based Rendering (DIBR)is a promising candidate for efficient multi-view 3D video multicast because many views can be synthesized and thereby no longer necessary to be transmitted into the network. Nevertheless, DIBR is computationally intensive and may overwhelm the mobile devices. Recently, an emerging paradigm, Mobile Edge Computing (MEC), is a good candidate for network edge to support DIBR in multi-view 3D video multicast. Therefore, we formulate a new problem, named Multi-view Multicast Synthesis and Delivery (MMSD), design an efficient algorithm, named Merge Search Forest Algorithm (MSFA), and prove that MSFA is an O(1)-approximation algorithm when the view distance constraint for synthesis is 2. Simulation results manifest that MSFA outperforms the existing approaches by 30% to 50% of the total communication and computation cost.

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