针对3D-HEVC的多视点视频加深度图的编码格式和四叉树编码结构所带来的编码复杂度问题，提出了一种深度图像快速帧内预测模式选择算法。首先，从深度视频序列中以最优的深度图最大编码单元（largest coding unit，LCU）划分深度为标签获取训练集；其次，构建了适用于LCU的Cu深度快速选择卷积神经网络（fast selecting Cu’s depth-convolutionalneural network，FSCD-CNN）；最后，对深度图LCU进行划分深度预测，跳过部分编码模式决策，实现最佳LCU划分。实验结果表明，与相关文献对比，所提算法在保持了编码性能的同时平均减少了15%的编码时间，实验验证了其有效性和可靠性。
In view of the coding complexity caused by the encoding format of multiview video plus depth map and the quadtree coding structure in 3D-HEVC, a fast intra prediction mode selection algorithm for depth images based on FSCD-CNN (fast selecting cu’s depth-convolutional neural network) is proposed. First, a training set is obtained by dividing the depth of the optimal depth map LCU (largest coding unit) of a depth video sequence as labels. Second, a FSCD-CNN network is constructed, which is suitable for deep decision-making of LCU. At last, the optimal division of LCU is achieved by carrying out the depth-division prediction of depth map LCU and skipping some coding mode decisions. Experimental results show that the proposed algorithm could reduce the coding time by 15% on average while maintaining the same coding performance as other relevant literatures, and verify the effectiveness and reliability of this method.
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