Signaling Subpicture IDs in Subpicture Based Video Coding A More Flexible Way to Split and Stream Video

This patent describes a technique for labelling the separate regions of a compressed video picture so a decoder always knows how to reassemble them. It comes from Huawei Technologies Co., Ltd., the Chinese technology company and a major contributor to modern video coding standards.

The Problem

Modern video compression can divide a single frame into independent regions, called subpictures, so that different parts of an image can be coded, extracted, or streamed separately. This is useful for things like 360-degree video, video conferencing layouts, and picking out a region of interest without decoding the whole frame. But it only works if the decoder can reliably match each region to its identifier. Those identifiers, the subpicture IDs, can be defined at different levels of the bitstream, and if a stream is edited or spliced the mapping can become ambiguous. The problem is deciding where the subpicture ID mapping should be signalled so that decoders interpret it consistently every time.

What This Invention Does

The invention sets rules for where in the bitstream the subpicture ID mapping is carried. A decoder receives a bitstream containing a sequence parameter set, a picture parameter set, and subpictures associated with a subpicture ID mapping. A flag in the sequence parameter set tells the decoder which of two places to look: when the flag has one value the mapping is signalled in the sequence parameter set, and when it has the other value the mapping is signalled in the picture parameter set. The decoder then obtains the mapping from whichever set the flags indicate. Putting the mapping in the higher-level sequence parameter set suits video where the layout stays fixed, while allowing it in the picture parameter set gives flexibility for streams whose regions change. By making the signalling explicit, the design removes ambiguity and keeps subpicture extraction reliable through editing and splicing.

Key Features

• Explicit signalling flag. A flag in the sequence parameter set specifies whether the subpicture ID mapping is carried in the sequence parameter set or the picture parameter set.
• Two placement options. The mapping can live at the sequence level for fixed layouts or the picture level for streams whose regions vary.
• Deterministic decoding. The decoder always knows where to read the mapping, so subpictures are reassembled consistently.
• Supports region extraction. Reliable IDs let a decoder pull out individual subpictures without processing the entire frame.
• Standards-aligned. The approach fits the subpicture tools introduced in the latest generation of video coding standards.

Who Is Behind It

The applicant is Huawei Technologies Co., Ltd., a global supplier of telecommunications and consumer electronics that is heavily involved in developing international video coding standards. The named inventor is Ye-Kui Wang, a well-known contributor to video compression standardisation. This filing is a divisional application from an earlier related Australian application.

Why It Matters

Video is the largest single category of internet traffic, so small gains in how efficiently and flexibly it can be coded ripple across streaming services, video calls, and immersive media. Subpicture tools underpin features like efficient 360-degree video and adaptive layouts, and clear signalling rules are what let different manufacturers’ decoders interoperate. Protecting these contributions in Australia reflects how central standardised video coding, such as Versatile Video Coding, has become to everyday media.

Related Concepts

• Versatile Video Coding – the recent standard whose subpicture tools this invention refines.
• Data compression – the general field that video coding belongs to.
• Bitstream – the coded data structure where the subpicture mapping is signalled.
• 360-degree video – an application that relies on independently coded regions.
• High Efficiency Video Coding – the previous standard generation this work builds on.

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AU 2026202006 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.