Imaging Apparatus Region Exposure Control for HDR Noise Reduction

Solution Overview

Problem

Conventional imaging apparatuses face challenges in capturing high dynamic range scenes due to underexposure or overexposure, leading to increased noise and motion blur, which affect image recognition and compression efficiency.

Innovation Solution

An imaging apparatus that divides the image into regions and adjusts exposure time and gain based on detected motion and luminance, with limitations set on these adjustments to prevent noise and blur.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the gain is increased for the region imaged under darker exposure conditions, then the dynamic range capture is improved, but noise in the image increases

Engineering Contradiction:

Improvedynamic range captureVSAvoidnoise

Core Design Contradiction:

Illumination intensityVSObject-affected harmful factors

Solution Approach 1:

The image is divided into multiple regions with different exposure conditions. The determination unit sets limitation on adjustment range of exposure time and gain for each region based on motion region detection results, allowing different regions to have optimized exposure parameters that balance dynamic range capture and noise reduction

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically adjusts exposure time and gain parameters based on real-time motion region detection. The determination unit modifies exposure conditions according to the detected motion regions, making the exposure parameters adaptive rather than static across the entire image

Inventive Principle:

Principle #15Dynamics

2Illumination intensity

If the exposure time is increased for the dark region, then the dynamic range capture is improved, but motion blur occurs due to subject movement

Engineering Contradiction:

Improvedynamic range captureVSAvoidimage sharpness

Core Design Contradiction:

Illumination intensityVSManufacturing precision

Solution Approach 1:

The image is divided into multiple regions with different exposure conditions. The determination unit sets limitation on adjustment range of exposure time and gain for each region based on motion region detection results, allowing different regions to have optimized exposure parameters that balance dynamic range capture and noise reduction

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically adjusts exposure time and gain parameters based on real-time motion region detection. The determination unit modifies exposure conditions according to the detected motion regions, making the exposure parameters adaptive rather than static across the entire image

Inventive Principle:

Principle #15Dynamics

3Illumination intensity

If the exposure conditions are changed at the boundary portion to darker exposure conditions, then the HDR scene capture is improved, but misalignment at the boundary occurs due to time lag

Engineering Contradiction:

ImproveHDR scene captureVSAvoidboundary alignment

Core Design Contradiction:

Illumination intensityVSManufacturing precision

Solution Approach 1:

The system performs preliminary imaging to determine exposure conditions for each region before main imaging. Based on the preliminary imaging results, the determination unit sets appropriate exposure parameters and limitations for the main capture, allowing the system to prepare optimal settings in advance and reduce boundary misalignment

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts exposure time and gain parameters based on real-time motion region detection. The determination unit modifies exposure conditions according to the detected motion regions, making the exposure parameters adaptive rather than static across the entire image

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS11678060B2Apparatus, method for controlling apparatus, and storage medium

Publication Date: 2023.06.13 CANON KK

AI summary

An apparatus configured to divide a captured image into a plurality of regions and carry out imaging under a different exposure condition for each of the regions, includes an acquisition unit configured to acquire an exposure value for each of the regions in the captured image, a detection unit configured to detect a motion region based on the captured image, and a determination unit configured to determine an exposure time and a gain based on the exposure value for each of the regions and a result of detection of the motion region, wherein the determination unit sets a limitation on an adjustment range of at least any of the exposure time and the gain based on the result.