Sensor-Specific Noise Reconstruction for Image Denoising

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing image denoising methods struggle with complex noise models in real photographs due to varied noise sources and post-processing, often requiring large paired datasets and are computationally heavy, making them unsuitable for resource-constrained devices like smartphones.

Innovation Solution

A method using a generator and discriminator neural network with residual learning and autoencoder pathways to reconstruct image noise directly, incorporating sensor-specific noise information for improved denoising on devices with limited resources.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If traditional single-image denoising algorithms analytically model properties of images and noise, then the methods rely on limited human knowledge and assumptions about image prior, but this limits their capability in recovering complex image structures

Engineering Contradiction:
Improveease of implementing analytical noise modelingVSAvoidprecision of recovering complex image structures
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent replaces traditional analytical/mathematical modeling approaches with a data-driven deep learning approach. Instead of relying on hand-crafted image priors and analytical noise models, the system uses a trained neural network that automatically learns complex image structures and noise characteristics from training data, substituting mathematical mechanics with learned representations.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent transforms the denoising problem from a deterministic analytical approach to a probabilistic learning approach. By changing from fixed analytical models to learned parameters from training data, the system can adapt to different noise characteristics and image content, improving recovery of complex structures while maintaining implementation feasibility.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If modern denoising methods employ neural networks to learn mapping from noisy images to noise-free images, then deep learning is capable of representing complex properties of images and noise, but training these models requires large paired datasets

Engineering Contradiction:
Improveprecision of representing complex image and noise propertiesVSAvoidquantity of paired training data required
Core Design Contradiction:
Manufacturing precisionVSQuantity of substance

Solution Approach 1:

The patent extracts and separates the noise modeling task from the overall denoising process. By using an unsupervised autoencoder pathway to specifically model noise characteristics independently, the system reduces its dependency on large paired datasets for noise representation, as the noise model can be trained separately without requiring clean-ground truth pairs.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent divides the denoising network into two distinct pathways: a supervised regression pathway for clean image estimation and an unsupervised autoencoder pathway for noise modeling. This segmentation allows each pathway to be trained with appropriate data requirements, reducing the overall demand for large paired datasets while maintaining precision in representing complex properties.

Inventive Principle:
Principle #1Segmentation

3Manufacturing precision

If GAN approach to denoising comprises generator and discriminator modules optimized with alternating gradient descent methods, then the generator samples from prior distribution and tries to model target distribution, but this approach is computationally heavy

Engineering Contradiction:
Improveprecision of modeling target distributionVSAvoidcomputational power required
Core Design Contradiction:
Manufacturing precisionVSPower

Solution Approach 1:

The patent extracts the noise modeling function from the GAN framework and implements it as a separate unsupervised autoencoder pathway. This removes the computationally heavy discriminator and alternating optimization process, retaining only the essential generative capability while significantly reducing computational power requirements.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent segments the denoising task into a supervised regression component and an unsupervised noise modeling component. This segmentation eliminates the need for the full GAN adversarial training process, reducing computational complexity while maintaining the ability to model complex image and noise properties through the two pathways working in parallel.

Inventive Principle:
Principle #1Segmentation

4Adaptability or versatility

If conditional GAN extends the formulation by providing the generator with additional labels, then the generator takes the form of encoder-decoder network, but this increases device complexity

Engineering Contradiction:
Improveadaptability to different conditioning labelsVSAvoidcomplexity of encoder-decoder network structure
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent creates a universal dual-pathway architecture where the supervised regression pathway can handle various denoising tasks with different conditioning information, while the unsupervised autoencoder pathway universally models noise characteristics. This multi-functional design provides adaptability to different scenarios without requiring separate complex encoder-decoder networks for each condition.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP4055555B1Noise reconstruction for image denoising
Publication Date: 2025.07.30 HUAWEI TECH CO LTD
  • EP4055555B1 patent drawingFigure 1(a)~2
  • EP4055555B1 patent drawingFigure 3
  • EP4055555B1 patent drawingFigure 4

AI summary

An apparatus (901) for denoising an image, the apparatus (901) having a processor configured to receive an input image, implement a trained artificial intelligence model to form an estimate of a noise pattern in the input image and form an output image by subtracting the estimate of the noise pattern from the input image, the model being configured to form the estimate of the noise pattern such that the estimate of the noise pattern is representative of a noise pattern that is characteristic to a specific image sensor type.