LL-HLS Packager Encryption Ready Format
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Low Latency HTTP Live Streaming (LL-HLS), packagers face challenges in estimating encrypted segment sizes due to encryption changes, leading to additional processing costs and size fluctuations, which are not predictable before or after encryption.
Innovation Solution
The introduction of a low latency encryption ready format that includes encryption-specific boxes and padding, allowing the just-in-time packager to maintain predictable segment sizes before and after encryption, thereby eliminating size changes during the encryption process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If encryption is applied to media segments, then security is improved, but segment size becomes unpredictable and processing complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing the size of encryption overhead (encryption boxes and padding) before actual encryption occurs. The packager determines the encrypted segment size by adding the clear segment size to the pre-calculated encryption overhead, allowing playlist generation without performing actual encryption first. This resolves the contradiction by enabling security-ready packaging without the complexity of real-time encryption processing.
2Reliability
If encryption boxes and padding are added during packaging, then security is improved, but segment size fluctuates requiring additional processing
Solution Approach 1:
The patent calculates the encryption overhead (size of encryption boxes and padding) in advance, before actual encryption. This preliminary calculation allows the packager to determine the final encrypted segment size without performing encryption, enabling efficient playlist generation and maintaining high packaging productivity while ensuring security requirements are met.
Solution Approach 2:
The patent introduces an intermediary calculation step that determines encrypted segment size by adding the clear segment size to the pre-calculated encryption overhead. This intermediary approach avoids the need to actually perform encryption just to determine size, thereby maintaining packaging efficiency while accounting for security-related size increases.
3Measurement precision
If decryption is performed to determine segment size, then accurate byte ranges are achieved, but processing time increases
Solution Approach 1:
The patent performs preliminary calculation of encryption overhead size before encryption occurs. By determining the size contribution of encryption boxes and padding in advance, the system can accurately specify byte ranges in playlists without performing decryption or actual encryption, thereby achieving measurement precision without the time cost of cryptographic operations.
Data Source
AI summary
Techniques for packaging media content in a low latency encryption ready format for streaming are described herein. In accordance with various embodiments, one or more packagers that include create an intermediate unit including at least one data portion from media content. The packager(s) further determine a size for reformatting the intermediate unit, where the size can include a padding amount for the at least one data portion. The packager(s) also package the intermediate unit to a reformatted partial segment according to the size without encrypting the at least one data portion, including injecting into the partial segment at least one encryption specific box and injecting padding into the at least one data portion according to the padding amount. The packager(s) then package the reformatted partial segment for streaming while maintaining the size, including generating a manifest for streaming the media content specifying the size of the reformatted partial segment.