HDR Image Composition with Peak Luminance Range Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for generating composite images fail to maintain consistent brightness and gradation when combining High Dynamic Range (HDR) images with different peak luminance values, leading to undesirable brightness differences in the composite image.
Innovation Solution
An image processing apparatus and method that acquires multiple images, decides a peak luminance value for the composite image, and performs additive composition while ensuring the signal level of each pixel falls within the output dynamic range set by the peak luminance value, either by clipping or converting the dynamic range of individual images before composition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If additive composition is performed on HDR images with different peak luminance values, then the composite image can be generated, but brightness discrepancies and gradation reversal occur in the output
Solution Approach 1:
The patent applies preliminary action by deciding the peak luminance value of the composite image before performing additive composition. The processor determines the appropriate peak luminance value based on the input HDR images, then uses this predetermined value to control the composition process, ensuring that pixel signal levels are properly scaled and clipped to avoid brightness discrepancies and gradation reversal in the final composite image.
2Device complexity
If the peak luminance value is not controlled in HDR image composition, then processing is simpler, but the output image exhibits undesirable brightness and gradation expressions
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the peak luminance value parameter during the composition process. The processor modifies the pixel signal levels based on the decided peak luminance value, applying appropriate scaling and clipping operations. This parameter control ensures that the composite image maintains accurate gradation expression and brightness characteristics without requiring complex additional processing steps.
Data Source
AI summary
An image processing apparatus includes at least one processor and at least one memory containing instructions that cause the at least one processor to be configured to function as an acquisition unit, a decision unit, and a generation unit. The acquisition unit is configured to acquire a plurality of images including at least one High Dynamic Range (HDR) image. The decision unit is configured to decide a peak luminance value of the composite image. The generation unit is configured to generate the composite image by executing additive composition processing using the plurality of images. The generation unit controls the additive composition processing so that a signal level of each pixel of the composite image falls within an output dynamic range whose maximum value is set to a signal level corresponding to the peak luminance value decided by the decision unit.