Obviousness

Based on the provided prior art analysis, here is an analysis of the obviousness of US patent 10,778,989 under 35 U.S.C. § 103.

Obviousness Analysis (35 U.S.C. § 103)

An invention is considered obvious if the differences between the invention and the prior art are such that the invention as a whole would have been obvious at the time of invention to a person having ordinary skill in the art (PHOSITA). This analysis considers whether a PHOSITA would have been motivated to combine or modify existing prior art references to arrive at the claimed invention with a reasonable expectation of success.

For the purpose of this analysis, a PHOSITA in the field of video coding circa 2016 would be an engineer or computer scientist with a degree in a relevant field and practical experience with video compression standards like H.264/AVC and H.265/HEVC. This individual would be intimately familiar with block-based predictive coding, including various intra-prediction modes and the goal of minimizing the prediction residual to achieve higher compression efficiency.

The core inventive concept of US 10,778,989, as distinguished from the cited prior art, is the "rolling intra prediction" mechanism. This involves using newly predicted pixels within a block as reference samples for predicting subsequent pixels in the same block. The cited references, Wang (US 2010/0111175 A1) and Samsung (US 2007/0053433 A1), both teach the conventional method where the prediction for an entire block is based exclusively on a static set of reference samples from adjacent, previously reconstructed blocks.

An argument for the obviousness of the independent claims of the '989 patent could be constructed as follows:

Combination of Prior Art: Samsung (US 2007/0053433 A1) in view of the knowledge of a Person Having Ordinary Skill in the Art (PHOSITA).

1. Base Reference: Samsung (US 2007/0053433 A1)

Samsung provides a strong foundation, teaching most of the elements claimed in the '989 patent:

• A method for encoding/decoding an image partitioned into blocks.
• Selecting an intra-prediction mode for a current block.
• Using neighboring reference samples (from adjacent, previously coded blocks) to generate a predicted block.
• Determining a residual by subtracting the predicted block from the original.
• Encoding the residual and the selected mode into a bitstream.
• Reconstructing the block at the decoder by adding the predicted block and the decoded residual.

The key element missing from Samsung is the rolling prediction step: "determining at least some other of the predicted pixels based on the prediction function... with the at least some of the predicted pixels as inputs" (Claim 1).

2. Motivation to Modify Samsung

A PHOSITA would have been motivated to modify the method taught by Samsung to solve a well-known problem inherent in conventional directional intra-prediction. The '989 patent itself articulates this problem in its background section: "directional prediction may introduce discontinuity along the direction that is perpendicular to the given angle. Since such discontinuity is introduced by the prediction process... it needs to be compensated in the residual block... [which] translates into non-zero coefficients at medium or high frequency positions... [that] are difficult to code".

A PHOSITA, tasked with improving compression efficiency, would seek to minimize these prediction-induced artifacts to create a "cheaper" residual to encode. They would recognize that as prediction moves further away from the reference samples at the block's edge, the prediction quality degrades, increasing the likelihood of such discontinuities.

The logical and intuitive solution to improve the prediction's internal consistency and smoothness would be to use the most relevant and proximate information available. As each new pixel in the block is predicted, its value represents the best available estimate for that location. It would be an obvious step for a PHOSITA to leverage this new information immediately, using the just-predicted pixel as a reference for its neighbors, rather than continuing to rely solely on the more distant reference samples at the block's edge. This modification directly addresses the problem of propagating a pattern smoothly across a block.

3. Reasonable Expectation of Success

A PHOSITA would have a high expectation that this modification would succeed. In signal and image processing, using locally generated data to inform the generation of subsequent data is a fundamental principle for ensuring continuity. By building the prediction block pixel-by-pixel (or row-by-row) in a defined "traversing order" and using the fresh output as input, the prediction would naturally become smoother. This would reduce the high-frequency artifacts in the residual, leading directly to better compression performance—the precise goal of the PHOSITA. The modification is not a leap into the unknown, but an application of known engineering principles to solve a known problem.

Conclusion on Obviousness

While the cited prior art from Wang and Samsung does not explicitly disclose the "rolling intra prediction" technique, an argument can be made that the '989 patent's claims would have been obvious to a PHOSITA. The Samsung reference teaches nearly all elements of the claimed invention. The sole inventive concept—the rolling prediction—represents a modification that a PHOSITA would have been motivated to make to solve the known problem of prediction-induced discontinuities inherent in Samsung's method. This modification would have been seen as a logical step with a reasonable expectation of improving prediction quality and, consequently, overall compression efficiency. Therefore, the independent claims of US 10,778,989 are vulnerable to an obviousness challenge under 35 U.S.C. § 103.