DASH Segment Timing Adjustment via MPD Delay Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Dynamic Adaptive Streaming Over Hypertext Transfer Protocol (DASH) systems fail to accurately account for delays in segment availability at receiver devices, leading to mismatches between announced and actual segment availability times due to network and device delays, clock drift, and processing times.
Innovation Solution
A receiver device adjusts segment availability times in the Media Presentation Description (MPD) based on actual delays and network jitter estimates, allowing for synchronized or unsynchronized clock conditions, and provides a delay adjustment message to modify segment requests and buffering requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If segment availability times in MPD correspond to encoder output times, then the MPD can be provided via OTA delivery with simple timing, but the announced availability times do not account for delivery path delays, receiver device processing delays, or clock drift, leading to mismatches between announced and actual segment availability
Solution Approach 1:
The patent applies preliminary action by pre-calculating and embedding delivery path delay estimates directly into the MPD segment availability times. The server estimates the total delivery delay (including network transmission and receiver processing) and adds this to the encoder output time when creating the MPD, so the availability times are pre-adjusted before transmission. This resolves the contradiction by maintaining simple OTA delivery while achieving accurate segment availability timing at the receiver.
2Productivity
If the MPD is provided via OTA delivery with encoder output times, then delivery is simple and efficient, but receiver devices experience delays due to delivery path, processing, and clock drift that are not accounted for in the announced availability times
Solution Approach 1:
The patent implements feedback by having the server estimate delivery path delays based on receiver device characteristics and network conditions, then use this feedback information to adjust segment availability times in the MPD. The system continuously monitors actual delivery performance and refines delay estimates, creating a closed-loop system that maintains reliable segment availability while preserving streaming efficiency. This resolves the contradiction by making the MPD timing adaptive to actual delivery conditions.
3Device complexity
If segment availability times do not account for receiver device processing delays and clock drift, then the MPD structure remains simple, but segments are not available at the announced times, causing streaming errors
Solution Approach 1:
The patent applies parameter changes by modifying the segment availability time parameter in the MPD to include estimated delivery path delays. Instead of using raw encoder output times, the server transforms this parameter by adding delay estimates that account for network transmission, device processing, and clock drift. This resolves the contradiction by keeping the MPD structure simple while changing the timing parameter values to reflect actual segment availability, making segment requests easier to execute correctly.
Data Source
AI summary
The systems, methods, and devices of the various embodiments enable a receiver device to adjust timing of requests for segments based on the actual times when the segments will be available on the receiver device. In various embodiments, a receiver device may be enabled to modify a segment availability timeline in which the availability times of the segments are adjusted to provide the actual times when segments will be available on the receiver device. In various embodiments, segment availability time adjustments may be made at a service layer of the receiver device. In various embodiments, segment availability time adjustments may be made by a client application on the receiver device. In the various embodiments, a network delay jitter estimate may be provided. In an embodiment, a network delay jitter estimate may be provided in a segment availability timeline.