Speckle Noise Reduction in Digital Holography by 3D Adaptive Filtering

Area of Science:

• Optics
• Image Processing
• Holography

Background:

• Digital holography reconstructs 2D/3D object information from interference patterns.
• Speckle noise is a major challenge, degrading reconstructed image quality.

Purpose of the Study:

• To propose and evaluate a novel speckle noise reduction method for digital holography.
• To enhance the quality of reconstructed holographic images while preserving fine details.

Main Methods:

• A novel speckle noise reduction method based on 3D adaptive filtering.
• Processing a stack of holograms with uncorrelated speckle patterns using an adapted 3D Frost filter.
• Exploiting statistical adaptivity for noise suppression and detail preservation.

Main Results:

• The 3D adaptive filtering technique significantly enhances reconstruction quality.
• Reduced normalized standard deviation by up to 40% and improved structural similarity index by up to 60% compared to other filters.
• Optical experiments validated the method's effectiveness using image quality metrics.

Conclusions:

• Adaptive 3D filtering is a promising approach for mitigating speckle noise in digital holography.
• The proposed method effectively reduces noise while maintaining structural integrity in reconstructions.
• This technique offers practical benefits for digital holography applications.