Multicast Video Error Recovery via Restart Sub-streams
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multimedia content delivery systems face issues such as transmission losses, startup delays, video quality degradation, and lack of flexibility in error recovery, particularly in unicast and multicast systems over commodity networks like the Internet.
Innovation Solution
The implementation of an adaptive multipath streaming system using multiple description coded video with a restart mechanism, which includes a buffer, selector, and analyzer to maintain constant video quality, enhance error resiliency, and minimize startup delays by selecting optimal transmission paths and substituting lost frames with frames from a restart sub-stream.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If retransmission is used to recover from packet loss, then video quality is improved, but startup delay increases and system complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-encoding multiple descriptions of the video content before transmission. Each description is independently decodable, allowing the receiver to reconstruct video content even if some packets are lost during transmission. This eliminates the need for retransmission and reduces startup delay while maintaining video quality.
Solution Approach 2:
The patent segments the video content into multiple independent descriptions, where each description contains sufficient information for basic video reconstruction. This segmentation allows the system to transmit redundant information in parallel rather than requiring sequential retransmission, thereby improving reliability without increasing startup delay.
2Reliability
If large buffer is used to absorb transmission jitter, then video quality is improved, but device complexity and memory requirements increase
Solution Approach 1:
The patent applies preliminary action by pre-synchronizing multiple descriptions at the encoder side and organizing them into temporally aligned packets. This preliminary synchronization allows the receiver to process descriptions in parallel with minimal buffering, reducing memory requirements while maintaining video quality through error recovery capabilities.
3Reliability
If multiple description coding is used for error recovery, then reliability is improved, but device complexity increases
Solution Approach 1:
The patent segments video content into multiple independent descriptions that can be transmitted separately and reconstructed at the receiver. Each description is self-contained and can be decoded independently, providing error recovery capability without requiring complex inter-dependent coding structures.
Solution Approach 2:
The patent creates a universal coding structure where multiple descriptions serve multiple functions: they provide both the primary video content and the error recovery mechanism. Each description can function as a complete video stream on its own, eliminating the need for separate error recovery systems and reducing overall system complexity.
4Reliability
If retransmission is implemented for lost packets, then video quality is improved, but productivity decreases due to additional latency
Solution Approach 1:
The patent applies preliminary action by encoding all necessary error recovery information into multiple descriptions before transmission begins. This eliminates the need for post-transmission retransmission operations, reducing latency and improving streaming efficiency while maintaining video quality through the redundant descriptions already present in the stream.
Data Source
AI summary
An embodiment of the present invention includes a receiver, and a selector. The receiver receives a default stream and N restart sub-streams from a transmitter over a transmission path, N is an integer equal to at least 1 and is selected according to a selection. The default stream is coded by a multiple description (MD) coding. The N restart sub-streams are coded by a predictive coding and sampled according to a sampling pattern. The default and N restart sub-streams correspond to a media content. The selector selects a receiving stream from the default stream and one of the N restart sub-streams according to a loss status in the default stream.