Some patent holders and pools designate their patents as relevant or essential to a standard without proper scrutiny or analysis. As part of an ongoing series examining this dubious practice, we highlight U.S. Patent 9,838,714. The ‘714 patent is owned by the Electronics and Telecommunications Research Institute (ETRI), is purportedly essential to the H.265 (HEVC) standard as part of the Access Advance Patent Pool, and is part of a family of at least 29 applications globally. It should not be considered essential.
The ‘714 patent is directed to the prediction phase of video coding, specifically, how to scan the decoded signals during intra-prediction. In this process, there is a specific order in which the values of a block (e.g., a 4x4 or 8x8 transform block) are processed. The ‘714 patent requires that the first row or column is scanned first, before any other column or row. See, e.g., claim 1 (“scanning entropy-decoded signals of a first row with priority so that all of the entropy-decoded signals of the first row are scanned prior to scanning entropy-decoded signals of any other row”).
In contrast, the HEVC standard does the opposite. As illustrated below, the HEVC standard requires scanning in “reverse order,” meaning that the last row is scanned first (from right to left) or the last column is scanned first (from bottom to top). See HEVC, § 7.3.8.11.
See T.Nguyen, “Transform coding techniques in HEVC,” IEEE Journal of Selected Topics in Signal Processing, vol. 7, no. 6, 978-989, Dec. 2013. The HEVC standard can scan in the diagonal (§ 6.5.3), horizontal (§ 6.5.4), or vertical (§ 6.5.5) directions for intra-mode prediction, but again, it does so in the “reverse order” direction, not the direction claimed by the ’714 patent.
Thus, the ‘714 patent does not appear to be essential to the HEVC standard even though it has been declared essential and actively licensed as being so. The public would benefit from appropriate scrutiny of such large patent pools that allegedly cover critical technical standards.