International organisation for standardisation organisation internationale de normalisation

Other (3)

(Chaired by A. Vetro)

14.1.1.1.1.1.1.1.162JCT3V-G0071 The removal of quad-tree limitation for depth maps [S. Yoo, J. Heo, S. Yea (LGE)]

This proposal has already been discussed in the context of CE2. No action, but proponents may study further.

14.1.1.1.1.1.1.1.163JCT3V-G0202 Cross check of removal of quad-tree limitation for depth maps (JCT3V-G0071) [J. Y. Lee, C. Kim (Samsung)] [late]

14.1.1.1.1.1.1.1.164JCT3V-G0151 AHG13: Results with quarter resolution depth map coding [S. Shimizu, S. Sugimoto (NTT)]

This contribution reports the result of quarter resolution depth map coding on MV-HEVC. In the simulation, VSO was activated for quarter resolution depth map coding with assuming the nearest neighbour upsampling would be performed during view synthesis. Experiments reportedly show that about 3.38% bit rate reduction and 6.22% bit rate increase for coded and synthesized views, respectively, with saving about 30% decoder runtime.

The main benefit of reduced resolution depth is to reduce the decoder run time, or other implementation factors such as memory or throughput.

It was observed that VSO gives significant improvement and uses a simple nearest neighbor upsampling. It would be desirable to use a more complex up-sampling filter to interpolate the depth values used for rendering, but this would need to be consistent with that used for VSO. It might be beneficial if VSO used a more complex up-sampling process.

The contribution also analyzes the impact of reduced resolution depth on the coding tools in 3D-HEVC. There would be substantial work involved to support reduced resolution depth with all the 3D-HEVC coding tools.

The contribution recommends supporting reduced resolution coding of depth in the software.

The MV-HEVC specification supports reduced resolution depth since auxiliary pictures can have a different spatial resolution than the primary pictures.

There were some reservations to adopt this into the software since it doesn’t provide a benefit in terms of coding efficiency. Also, there was some concern that there might be a desire to add other scaling ratios and make the software more complex.

There was some interest to integrate into the software so that this capability could be studied further.

It was suggested that the software might be integrated into a branch of the software, or simply shared with interested parties. It was noted that even the branch would need to be maintained and there were no volunteers to do this. As a result, it was agreed to simply share the software with interested parties.

It was also agreed that the mandates of the AHG13 have been completed, and there is no need to continue the activity.

8.