Intra Prediction Candidate Selection for Lower-Bitrate Image Coding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The increasing demand for high-resolution and high-quality images leads to higher transmission and storage costs due to increased bit rates, necessitating improved image encoding/decoding efficiency and effective intra prediction methods.

Innovation Solution

An image encoding/decoding method and apparatus that utilizes various intra prediction techniques, including template-based intra mode derivation, decoder side intra mode derivation, linear interpolation intra prediction, and other methods to construct an intra prediction candidate list, enhancing encoding/decoding efficiency and enabling effective intra prediction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If high-resolution and high-quality image data is transmitted, then image quality is improved, but transmission cost and storage cost increase

Engineering Contradiction:
Improveimage qualityVSAvoidtransmission cost and storage cost
Core Design Contradiction:
Measurement precisionVSLoss of energy

Solution Approach 1:

The patent extracts and transmits only the essential visual information by using intra prediction to generate prediction blocks that approximate the original image data. The residual data (difference between original and prediction) is transmitted instead of the full high-resolution image, thereby maintaining image quality while reducing transmission and storage costs.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the representation parameters of image data by transforming the original image into a prediction-based representation. Instead of storing/transmitting raw pixel values, the system uses prediction modes, reference block indices, and residual coefficients, which require fewer bits while preserving image quality.

Inventive Principle:
Principle #35Parameter changes

2Loss of energy

If conventional image compression technology is used, then transmission cost is reduced, but image quality deteriorates

Engineering Contradiction:
Improvetransmission costVSAvoidimage quality
Core Design Contradiction:
Loss of energyVSMeasurement precision

Solution Approach 1:

The patent performs preliminary intra prediction processing on the image data before transmission. By generating prediction blocks based on neighboring blocks within the same picture, the system prepares a compressed representation that maintains spatial relationships and visual quality, reducing the need for aggressive compression that would degrade image quality.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces prediction blocks as an intermediary between the original image data and the transmitted bitstream. These prediction blocks serve as a mediator that captures the essential visual information while requiring fewer bits for transmission, thus balancing transmission cost and image quality.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If intra prediction candidate list is constructed with multiple prediction modes, then prediction accuracy is improved, but computational complexity increases

Engineering Contradiction:
Improveprediction accuracyVSAvoidcomputational complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent implements a dynamic intra prediction candidate list that adapts to the characteristics of the current block and neighboring blocks. The candidate list is constructed by evaluating multiple prediction modes but selectively including only those that provide significant improvement, thereby balancing prediction accuracy with computational complexity through adaptive decision-making.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies partial action by constructing an intra prediction candidate list that includes a selective subset of prediction modes rather than exhaustively evaluating all possible modes. This approach achieves sufficient prediction accuracy for most blocks while reducing computational complexity by avoiding unnecessary evaluation of less relevant prediction modes.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP4694135A2Intra prediction-based image encoding/decoding method and device, and recording medium for storing bitstream
Publication Date: 2026.02.11 LG ELECTRONICS INC
  • EP4694135A2 patent drawingFigure 1
  • EP4694135A2 patent drawingFigure 2
  • EP4694135A2 patent drawingFigure 3

AI summary

Provided are an image encoding/decoding method and device. The image decoding method, according to the present disclosure, comprises the steps of: on the basis of intra prediction information of neighboring blocks of the current block, acquiring one or more candidate intra prediction information; on the basis of the one or more candidate intra prediction information, configuring an intra prediction candidate list; acquiring an intra prediction candidate index representing one candidate intra prediction information included in the intra prediction candidate list; and generating a prediction block of the current block by performing intra prediction on the basis of the candidate intra prediction information indicated by the intra prediction candidate index, wherein the candidate intra prediction information may include at least one among template based intra mode derivation (TIMD) information, decoder side intra mode derivation (DIMD) information or linear model information, linear interpolation intra prediction (LIP) information, position dependent intra prediction (PDPC) information, multi reference line (MRL) information, template-based multiple reference line (TMRL) information, intra sub-partition (ISP) information, matrix-based intra prediction (MIP) information, interpolation filter information, mode dependent intra smoothing (MDIS) information, combined inter and intra prediction (CIIP) information, spatial geometric partition mode (SGPM) information, template matching intra prediction (intraTMP) information, intra prediction directional mode information, extended planar information, intra prediction fusion information, neighboring reference sample characteristics information or intra block copy (IBC) information.