RTP Packet Extension Header for Jitter Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for calculating jitter information in wireless video transmission networks are inaccurate due to factors like multipath fading and time variability, leading to decreased video quality and frame loss, necessitating a more precise method for analyzing network conditions and optimizing video transmission.
Innovation Solution
A jitter correction method and apparatus that determine and transmit a video frame's timestamp and transfer time within RTP packets, allowing for accurate jitter calculation by using the transfer time instead of the timestamp, thereby correcting for network-related errors and improving video quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If jitter information is obtained through RTCP during video stream transmission, then QoS information including delay and loss rate can be transmitted, but the jitter information becomes inaccurate due to network factors like multipath fading and time variability
Solution Approach 1:
The patent introduces an extension header as an intermediary carrier to transport the actual video frame timestamp from the video data to the receiver. This intermediary structure allows the receiver to calculate jitter using the original video timestamp rather than relying on potentially inaccurate RTCP-derived jitter information, thereby resolving the contradiction between measurement precision and reliability
Solution Approach 2:
The patent implements a feedback mechanism where the receiver calculates actual jitter based on the transmitted video timestamp and sends this accurate jitter information back to the transmitter through RTCP. This feedback loop enables continuous correction and improvement of jitter measurement accuracy, addressing the reliability issue caused by initial inaccurate jitter data
2Productivity
If video frames are transmitted in wireless channel environment with multipath fading, then real-time multimedia service can be provided, but picture quality deteriorates and frame loss occurs
Solution Approach 1:
The patent applies preliminary action by embedding the original video frame timestamp in the extension header before transmission. This pre-prepared timestamp information enables the receiver to perform accurate jitter calculation without being affected by subsequent wireless channel impairments like multipath fading, thus maintaining both transmission speed and picture quality
Solution Approach 2:
The patent provides beforehand cushioning by including redundant timestamp information in the extension header that can compensate for the effects of wireless channel degradation. This preparatory measure ensures that even when picture quality deteriorates due to multipath fading, the jitter calculation remains accurate, protecting video transmission reliability
3Measurement precision
If RTP packets include extension header with transfer time, then accurate jitter calculation is enabled, but packet structure becomes more complex
Solution Approach 1:
The extension header serves multiple functions: it carries the video frame timestamp for jitter calculation, maintains compatibility with existing RTP processing, and provides a standardized structure that can be used across different video transmission scenarios. This multi-functionality justifies the added structural complexity by delivering significant measurement precision improvements
Solution Approach 2:
The patent changes the parameter representation by adding the extension header with transfer time information. This parameter addition transforms the RTP packet structure to enable precise jitter calculation, accepting increased complexity as a necessary trade-off for achieving accurate quality measurement in wireless environments
Data Source
AI summary
A jitter correction method of a transmitting device, a jitter correction method of a receiving device, a transmitting device, and a receiving device are provided. The jitter correction method of the transmitting device includes: determining a time stamp of a video frame; determining a transfer time of an real-time transport protocol (RTP) packet that includes at least a part of the video frame as a payload; generating the RTP packet including the time stamp and the transfer time; and transmitting the RTP packet to a receiving device.