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Updated: May 12, 2026
10:16
Digital Inline Holographic Microscopy (DIHM) of Weakly-scattering Subjects
Published on: February 8, 2014
Non-uniform deblurring in HDR image reconstruction.
Channarayapatna Shivaram Vijay1, Chandramouli Paramanand, Ambasamudram Narayanan Rajagopalan
1Department of Electrical Engineering, Indian Institute of Technology, Chennai, India.
Summary
This study presents a new method to deblur images captured with hand-held cameras, even in high dynamic range imaging. The technique effectively removes non-uniform blur caused by camera shake, recovering the original scene details.
Area of Science:
- Computer Vision
- Image Processing
- Computational Photography
Background:
- Hand-held cameras often produce blurred images due to camera shake, especially in high dynamic range imaging (HDR) applications.
- Camera shake introduces non-uniform blurring, involving both translations and rotations, complicating image restoration.
- Existing methods struggle with non-uniform blur and varying exposure levels in multi-image sequences.
Purpose of the Study:
- To develop a robust method for deblurring images affected by camera shake in high dynamic range imaging.
- To extract a clear, latent irradiance image from a sequence of blurred and differently exposed frames.
- To address both scenarios where only high exposures or all frames are blurred.
Main Methods:
- Utilizing transformation spread functions (TSFs) to model camera motion-induced blur.
- Estimating TSFs from locally derived point spread functions (PSFs) based on their linear relationship.
- Employing a cost functional minimization approach to reconstruct the scene irradiance.
Main Results:
- Successfully deblurred images with non-uniform camera shake.
- Effectively handled sequences with varying exposure levels.
- Demonstrated performance in both investigated cases: blurred high exposures and blurred all frames.
Conclusions:
- The proposed method effectively restores latent irradiance images from blurred, multi-exposure sequences.
- TSF modeling provides an accurate representation of camera motion blur for image deblurring.
- This technique offers a significant advancement in handling challenging imaging conditions in HDR photography.
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