Department of Electrical and Electronics Engineering2024-11-0920191520-921010.1109/TMM.2018.28566292-s2.0-85049985587http://dx.doi.org/10.1109/TMM.2018.2856629https://hdl.handle.net/20.500.14288/10642This paper proposes methods for rate adaptation by motion-based spatial and temporal resolution selection in both mesh-connected and selective-forwarding-unit (SFU) connected WebRTC videoconferencing using scalable video coding. In the mesh-connected case, the proposed motion-adaptive spatial/temporal layer selection allows each peer to send video to different peers with different terminal types and network rates at different rates using a single encoder. In the SFU-connected case, motion-adaptive rate control is used both at peers to adapt to the network rate between the sending peer and SFU by spatio-temporal resolution adaptation and at the SFU by layer selection to adapt to the network rate between the SFU and receiving peer. Experimental results show that our proposed motion-based rate adaptation achieves better perceptual video quality with sufficiently high frame rates and lower quantization parameter for video with high motion; and high spatial resolution and lower quantization parameter for video with low motion compared to simple rate-distortion model-based layer selection that does not use motion complexity, at the same rate.Computer scienceInformation systemsEngineeringSoftware engineeringTelecommunicationsJournal Article1941-0077457364400013Q1668