Prior art

To identify the most relevant prior art for US patent 11936876 and analyze its potential anticipation of claims under 35 U.S.C. § 102, I will use the patent's own cited references. The full patent text is explicitly provided and states, "The present principles relate generally to video encoding and decoding and, more particularly, to methods and apparatus for signaling intra prediction for large blocks for video encoders and decoders." It further discusses prior art within its "BACKGROUND" section, which is crucial for an obviousness analysis, but also contains explicit citations.

The patent document itself provides a "References Cited" section. However, the provided text snippets do not explicitly list all external "References Cited" in a separate section. Instead, the "BACKGROUND" section discusses relevant prior art, and the patent mentions "MPEG-4 AVC Standard" and "first prior art approach" and "further inter coding proposals". Therefore, I will extract these and any other explicitly mentioned prior art within the text.

Based on the provided full patent text, here are the identified prior art references and an analysis of their potential anticipation:

Identified Prior Art References from US11936876:

1. MPEG-4 AVC Standard (ISO/IEC Moving Picture Experts Group-4 Part 10 Advanced Video Coding standard/International Telecommunication Union, Telecommunication Sector (ITU-T) H.264 Recommendation)

   • Full Citation: Not a formal patent citation, but a widely recognized video coding standard.
   • Publication/Filing Date: The patent indicates it is a "modern video coding standard" [cite: "BACKGROUND"]. The original MPEG-4 AVC Standard (H.264) was finalized in 2003. The priority date of US11936876 is 2009-07-01 [cite: "Priority date"]. Thus, this standard predates the patent.
   • Brief Description: Describes various coding modes to reduce spatial and temporal correlations in video. Specifically for intra pictures, all macroblocks are coded in intra modes, exploiting spatial correlations. It classifies intra modes into INTRA4×4, INTRA8×8, and INTRA16×16. It details the prediction modes for each (e.g., 9 for 4×4/8×8, 4 for 16×16, including vertical, horizontal, DC, and plane). It also describes the signaling for these modes using mb_type and transform_8x8_size_flag for 4x4/8x8, and mb_type values (1-24) for INTRA16x16. [cite: "BACKGROUND", "TABLE 1"]
   • Potential Anticipation (35 U.S.C. § 102): The MPEG-4 AVC Standard anticipates aspects of intra prediction for smaller block sizes (4x4, 8x8, 16x16), including specific intra prediction modes and their signaling. It would directly anticipate any claim language broadly covering intra prediction for blocks up to 16x16, the concept of spatial intra partition types (sip_type), and basic prediction modes like DC, vertical, and horizontal. This standard directly teaches "intra prediction" and "spatial intra partition type" for block sizes up to 16x16. Claims 1, 5, 11, and 15, which describe determining/signaling intra prediction and a single spatial intra partition type, have elements directly found in the MPEG-4 AVC Standard, particularly when applied to basic coding unit sizes of 16x16 or smaller, which are explicitly mentioned in the standard.

2. First Prior Art Approach (describing signaling for 32×32 or 64×64 blocks using a hierarchical coding structure)

   • Full Citation: Not a formal patent citation, but described as a "first prior art approach" in the patent's background. No specific document number is provided within the text.
   • Publication/Filing Date: The patent describes this as an "example of how large motion (Inter) partitions are signaled in extensions of the MPEG-4 AVC Standard" [cite: "BACKGROUND"]. This implies it predates the present patent, as it is presented as existing prior art that the current invention aims to improve upon for intra prediction. The priority date of US11936876 is 2009-07-01 [cite: "Priority date"].
   • Brief Description: This prior art addresses how signaling is performed for large motion (Inter) partitions, specifically for 32×32 or 64×64 blocks, utilizing a hierarchical coding structure. [cite: "BACKGROUND"]
   • Potential Anticipation (35 U.S.C. § 102): This reference anticipates the concept of hierarchical coding structures and signaling for large blocks (32x32, 64x64) in video coding, specifically within the inter prediction domain. While it is for inter prediction, the teaching of "hierarchical coding structure" for large blocks is present. This could potentially anticipate the structural elements of hierarchical splitting and merging described in the claims, though the application to intra prediction for these large blocks is explicitly stated as the gap addressed by the present patent. Claims 1, 5, 11, and 15 involve hierarchical layer intra prediction and splitting/merging from large block sizes to basic coding unit sizes. The underlying concept of hierarchical partitioning and signaling for large blocks, as described for inter prediction in this prior art, could be seen as anticipating the structural framework, even if the application domain (intra) is different.

3. Further Inter Coding Proposals (for an extension of the MPEG-4 AVC Standard using 32×32, 32×16, and 16×32 partitions)

   • Full Citation: Not a formal patent citation; described as a proposal for an "extension of the MPEG-4 AVC Standard." No specific document number is provided within the text.
   • Publication/Filing Date: The patent indicates this is an existing proposal ("inter coding has also been proposed for an extension of the MPEG-4 AVC Standard") [cite: "BACKGROUND"]. This implies it predates the present patent. The priority date of US11936876 is 2009-07-01 [cite: "Priority date"].
   • Brief Description: This describes proposed inter coding using larger partitions (32×32, 32×16, 16×32) and illustrates motion partitions for 32×32 blocks (FIG. 3). It details that 16×16 partitions can be further divided into 16×16, 16×8, 8×16, and 8×8, and 8×8 into 8×8, 8×4, 4×8, and 4×4. Crucially, it mentions signaling "SKIP mode or DIRECT mode... using an mb32_skip_flag in a way similar to that performed for other modes of the MPEG-4 AVC Standard." [cite: "BACKGROUND"] It also states, "If the mb32_type of a 32×32 indicates that a 16×16 partition is used, then the four 16×16 blocks are signaled in raster scan order by using the same syntax elements as macroblock_layer( ) in the MPEG-4 AVC Standard." [cite: "BACKGROUND"] For 64x64, "one more hierarchical layer is added." [cite: "BACKGROUND"]
   • Potential Anticipation (35 U.S.C. § 102): This reference directly anticipates the use of large block sizes (32x32, 64x64) and hierarchical partitioning for video coding. It explicitly teaches the splitting of blocks (e.g., 32x32 into 16x16s) and the signaling of these partitions using flags (mb32_skip_flag) and existing syntax elements (macroblock_layer()). [cite: "BACKGROUND"] Although applied to inter coding, the structural elements of "decoding a binary split signaling syntax element specifying that the large block is further split into four equally sized sub-blocks" (Claim 1), "partitioning the large block into the four equally sized sub-blocks" (Claim 1), and "decoding a second syntax element indicating a single spatial intra partition type for at least one basic coding unit sized sub-block" (Claim 1) are strongly anticipated. The patent itself notes that "macroblock_layer()" in H.264 includes mb_type for Intra_4x4, Intra_8x8, and Intra_16x16. [cite: "BACKGROUND", "TABLE 1"] Therefore, this prior art, in combination with the MPEG-4 AVC Standard, anticipates almost all structural aspects of the hierarchical partitioning and signaling, leaving only the explicit application to intra prediction for large blocks as the alleged novelty. Claims 1, 5, 11, and 15, particularly concerning the hierarchical splitting, the use of a binary split signaling syntax element, and the signaling of partition types for sub-blocks, are highly vulnerable to anticipation by this reference.

It is important to note that while the patent identifies a gap regarding how "large intra mode is signaled," [cite: "BACKGROUND"] the prior art discussed in its background appears to establish a strong basis for an obviousness argument (35 U.S.C. § 103) by teaching the individual components (intra prediction for small blocks, hierarchical partitioning and signaling for large inter blocks) and suggesting their combination. However, for direct anticipation under 35 U.S.C. § 102, each and every element of a claim must be present in a single prior art reference. The detailed description of "Further Inter Coding Proposals" comes closest to anticipating the structural elements of hierarchical partitioning and signaling, leaving the specific intra prediction for the large block itself (when not split) as a potentially distinguishing feature.