A Depth Information Based Fast Mode Decision Algorithm for Color Plus Depth-Map 3D Videos

With the advance of 3D display and related technologies, 3D video applications have been booming up recently. The color plus depth-map 3D video gains the attention for its relatively low storage and transmission bandwidth requirements as compared with stereo and multi-view videos. The color plus depth-map 3D video provides the depth information about the recorded content which brings new rooms for video processing and compression. This work reveals the usage of depth information for speeding up video encoding process. A novel fast mode decision algorithm based on depth information is proposed. The algorithm is also applicable to videos in which the associated depth-maps are not the ground-truth. By utilizing the depth information, we can classify scenes according to the associated depth and assign the appropriate modes. We can also deduce the configuration of the given macroblock by the associated depth information and select the suitable mode candidates; therefore, the encoding process will be speeded-up accordingly. Experimental results show that the proposed algorithm is faster than existing mode decision approaches with similar coding efficiency. The entire encoding time is reduced by about 63% for Standard Definition (SD) and High Definition (HD) formats while the Rate-Distortion (RD) performance is almost the same as compared with the exhaustive full mode decision approach.