Image Brightness Adjustment via Histogram Classification for Power Saving

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Portable terminals, such as mobile phones and PMPs, face high power consumption due to display driving units, which limits battery life, and existing methods to reduce power consumption, like lowering backlight brightness, do not maintain image brightness in power save mode.

Innovation Solution

An image processing method that classifies input images based on brightness histograms and applies corresponding brightness weighting functions to adjust pixel brightness, maintaining image brightness in low power consumption modes by using a tone mapping function and variable gains to control brightness distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the brightness of the light source (backlight) is reduced during power save mode, then power consumption is reduced, but image brightness deteriorates

Engineering Contradiction:
Improvepower consumptionVSAvoidimage brightness
Core Design Contradiction:
Use of energy by moving objectVSIllumination intensity

Solution Approach 1:

The patent applies different brightness weighting functions to different regions of the image based on their position and local characteristics. By analyzing the brightness histogram and classifying image regions, the system adjusts brightness locally rather than uniformly, allowing power reduction while maintaining perceived image quality in critical areas.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent changes the brightness parameter dynamically based on power mode and image characteristics. It uses brightness weighting functions with different gains (e.g., first gain for power save mode, second gain for normal mode) and adjusts these parameters according to the classified image categories, enabling adaptive brightness control that resolves the contradiction between power consumption and image brightness.

Inventive Principle:
Principle #35Parameter changes

2Use of energy by moving object

If uniform brightness adjustment is applied to all pixels, then power consumption is reduced, but image distortion occurs

Engineering Contradiction:
Improvepower consumptionVSAvoidimage quality
Core Design Contradiction:
Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent divides the image into different regions and applies position-dependent brightness weighting functions. Each pixel's brightness adjustment is determined by its specific position and the local image characteristics, preventing uniform adjustment that would cause distortion while still achieving overall power reduction.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the image processing into multiple stages: brightness histogram analysis, image classification into predetermined categories, position-based weighting function selection, and differential brightness adjustment. This segmentation allows sophisticated local control that maintains image quality while reducing power consumption.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP1918873B1Image processing method, medium and system
Publication Date: 2020.04.08 SAMSUNG ELECTRONICS CO LTD
  • EP1918873B1 patent drawingFigure 1~2
  • EP1918873B1 patent drawingFigure 3
  • EP1918873B1 patent drawingFigure 4

AI summary

An image processing method, medium, and system. The image processing method includes classifying an input image into predetermined image categories based on a feature of a brightness histogram of the input image, and adjusting a brightness of the input image based on grayscale functions corresponding to the image categories and positions of pixels making up the input image.