HDR Camera Bracketing with Dynamic Exposure Selection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electronic devices with image sensors have a limited dynamic range for image reproduction, which is half that of the human eye, and current HDR techniques use static parameters that limit range expansion.

Innovation Solution

Dynamically and automatically selecting exposure values for a sequence of images using a camera response function, capturing these images, and fusing them to generate HDR images, without relying on pre-defined LUT files.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If static LUT-based HDR techniques are used, then HDR images can be generated, but the dynamic range expansion is limited

Engineering Contradiction:

Improvedynamic range expansionVSAvoidparameter selection flexibility

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies dynamics by transitioning from static LUT-based exposure selection to dynamic exposure value calculation. The system computes exposure values in real-time based on the actual image histogram and camera response function, allowing the exposure bracketing sequence to adapt to varying scene conditions. This dynamic approach enables optimal dynamic range expansion for each specific imaging scenario rather than relying on pre-defined static parameters.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements parameter changes by calculating exposure values based on the image histogram and camera response function rather than using fixed LUT entries. The exposure values are dynamically adjusted according to the actual content and lighting conditions of each image, allowing the system to optimize the dynamic range for each specific scene. This parameter adaptation enables customized dynamic range expansion that matches the actual imaging requirements.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If pre-defined LUT files are used for exposure selection, then processing is simplified, but real-time optimization is lost

Engineering Contradiction:

Improveexposure value selection speedVSAvoidexposure value accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent applies self-service by having the system automatically calculate and select optimal exposure values based on its own captured image data and stored camera response function. Rather than relying on external pre-defined LUT files, the system uses its intrinsic capabilities (image sensor, processor, and camera response function) to self-optimize the exposure bracketing sequence. This self-service approach ensures real-time optimization while maintaining processing efficiency through automated histogram analysis and mathematical calculations.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS20250254433A1Electronic Devices and Corresponding Methods for Dynamically and Automatically Selecting Exposure Values for Bracketing Operations Generating High Dynamic Range (HDR) Images

Publication Date: 2025.08.07 MOTOROLA MOBILITY LLC

AI summary

An electronic device includes an image sensor and one or more processors operable with the image sensor. The one or more processors are operable to dynamically and automatically select-exposure values using a camera response function for the image sensor for a sequence of images to generate an HDR image. The one or more processors can cause the image sensor to capture the sequence of images using the exposure values selected and can fuse the sequence of images to create the HDR image.