The reliable internet stream transport (RIST) protocol is used for streaming video over the internet and requires time synchronisation to ensure that each frame is played out at the correct time. One method to ensure time synchronisation today in RIST productions is by utilizing the network time protocol (NTP). NTP has several issues and requirements that makes it a not ideal time synchronisation method in RIST productions and this thesis proposes a dynamic average time synchronisation (DATS) method as an option for using NTP in RIST productions. The DATS method uses a two-way synchronisation scheme to estimate the time offset between a video sender node and a video receiver node which is added to an average used as the time offset value. Additionally, it is explored whether or not a Kalman filter can further increase performance in DATS. Furthermore, the Kalman filter parameters were attempted to be optimized with a genetic algorithm. With a simulated \textit{testsrc FFmpeg} stream, the performance of DATS is evaluated and compared with the NTP implementation \textit{Chrony}. The metrics used in the evaluation was the playout delay and the error in time synchronisation which were calculated by periodical messages between a sender and receiver node. The results reveal that DATS performs slightly better without a Kalman filter but is slightly less robust without it. The results also indicated that DATS is comparable to NTP in an unloaded network, but is outperformed by NTP in a congested network.
| Identifer | oai:union.ndltd.org:UPSALLA1/oai:DiVA.org:ltu-97858 |
| Date | January 2023 |
| Creators | Malmström Berghem, Simon |
| Publisher | Luleå tekniska universitet, Institutionen för system- och rymdteknik |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Student thesis, info:eu-repo/semantics/bachelorThesis, text |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0026 seconds